Vannin' Home
Posted By: Don_F 95 G30 Tow Project. - April 24th 2016 3:46 pm

Hello I am new here. I have had a 1995 g30 cargo van since December. It was a fleet vehicle for a local electric company and has 106k on it. It mostly needs some TLC. The goal for this project is a reliable tow vehicle.

So far i have done:

Superior shift improver Kit, with a TD valve body plate, upgraded the throttle valve to a Sonnax .490

Replaced the shocks with KYB MonoMax shocks. Wired in a 7 way trailer plug plus a trailer brake control.

Added a tiny tach and trans temp gauge to the two empty areas in the right of the dash.

I have started replacing the door weatherstripping too, but that's not done.

The valve body work cured an extreme lag when shifting between drive and reverse. The 490 throttle valve firms up the shift a little when you step on it. 4l60e are known for problems, but hopefully this one will last a little longer.

The Kyb Monomax shocks are a big improvement over the factory shocks, but I wasn't thrilled when they showed up and the overall lengths were much different than the originals. The fronts are longer with a longer body and the rears are shorter and are almost fully extended at normal ride height. I didn't want to hassle with a return to Summit, but this is one area I may have done differently if I had known. I may just be being picky, but my thoughts are that Chevrolet designed the suspension with a certain amount of travel and restricting that so that a shock company can make one part number fit more cars is not what I was looking for on my van. Its going to be used on the freeway mostly so I went ahead an installed them. If the use was more dirt roads etc, I would have sent them back and dealt with the hassle of the returns.

Future plans are just more fixing and interior panels with e-track tie down points. Eventually I will swap out the 3.23 ratio for something more tow friendly to the 5.7.

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Posted By: frscke1 Re: 95 G30 Tow Project. - April 24th 2016 4:41 pm
Welcome to the site Don .... another nice bow tie !
Posted By: lukester Re: 95 G30 Tow Project. - April 25th 2016 1:36 am
welcome from Florida

Nice van.
Posted By: Don_F Re: 95 G30 Tow Project. - April 27th 2016 12:04 am
Thank you, there are a lot of nice vans here for inspiration!
Posted By: Don_F Re: 95 G30 Tow Project. - May 08th 2016 12:33 am
I have searched but I am not finding anything. My drivers side vent window latch is falling apart and the passenger one is not far behind. On my 95 they used plastic latches. I see Classic Industries has metal 1973-91 GM Truck Vent Window Handles (Kits) for both sides. Has anyone tried using the early vent window handles on a later van. From the pictures they look similar in function, but I cant be sure they fit unless I buy. Just hoping someone has run into this before me so I'm not taking as much of a chance. I took the drivers side apart, most of the parts look good but the plastic gaskets are deteriorating causing the looseness. GM wants crazy money for the passenger side assembly online and the drivers side is greyed out.
Posted By: frscke1 Re: 95 G30 Tow Project. - May 08th 2016 4:16 am
Write to 67 auto dismantling they have hundreds of them, all brands ... Tell them the guy with the big red van sent you...

http://67truck.com/

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Posted By: Don_F Re: 95 G30 Tow Project. - May 08th 2016 1:31 pm
Thanks, I can get used parts local. I looked and all the plastic washers are starting to crack and deteriorate, maybe not as bad as my drivers side, but its there. A used solution means that I will be in the same mess in a few years. If I can find a new solution I might be ahead. The vent window latch kits from Classic Industries for the Chevy trucks are only 10 each. I will take a chance and see what I can use, hopefully the full kit, but if not then possibly the parts.
Posted By: Don_F Re: 95 G30 Tow Project. - May 08th 2016 2:48 pm
I had second thoughts, this is supposed to be a tow vehicle project not a restoration, I just reassembled the original parts and tightened up the screw a bit to take up the slack from the cracked plastic washers.Its closing tightly now so its more secure than it was when it was loose. Hopefully in a few years when it does get bad again there will be a known solution.
Posted By: wbud Re: 95 G30 Tow Project. - August 02nd 2016 4:32 pm
Hi, Don!
found your review about problem with shock length on summitracing. Did you resolve this problem?
Have the same issue with shocks on my G30 1979.
Posted By: Don_F Re: 95 G30 Tow Project. - August 06th 2016 5:27 am
I have both sideas of the main cargo area done. I tried bending the plywood, but the cheap plywood delaminated when wet and didn't fit the corners as well as my two piece experiment so I just did that. Its nothing fancy, just finishing off the area to cut down on noise and have a finished surface to strap to. The ceiling is tomorrow. I did it once already, but i am not happy with the fit on a couple parts.

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Posted By: Don_F Re: 95 G30 Tow Project. - August 06th 2016 5:31 am
Originally Posted by wbud
Hi, Don!
found your review about problem with shock length on summitracing. Did you resolve this problem?
Have the same issue with shocks on my G30 1979.

No the problem would require another purchase. So far the shocks seem to be working pretty well and I am not terribly unhappy as this is a freeway and city van mostly. If it does become a problem. I will buy the Bilstein shocks next.
Posted By: 86ed Re: 95 G30 Tow Project. - August 07th 2016 4:35 am
Lookin good, what kind of material did you use?
Posted By: Don_F Re: 95 G30 Tow Project. - August 07th 2016 7:01 pm
.edited
Posted By: Don_F Re: 95 G30 Tow Project. - August 07th 2016 8:04 pm
Its $60 for a 45 ft roll and I ended up 5 ft short. So 50ft x 4ft roll should do the top and both sides along with the rear panels with some small bits left over.
Posted By: Don_F Re: 95 G30 Tow Project. - August 10th 2016 12:30 am
I am pretty much done, just one more piece to cut and cover on the top, but I am waiting on more material. I was looking at the sliding side door and thinking about making a door panel for that too. I see though the round lock knob on the inside sits right up to the door, no room for a .2 piece of wood behind it. My options look to be getting a hole saw slightly bigger than the knob so a door panel can sit around it, or just doing a half panel and leaving the upper panel as bare metal. Anyone else run into this? Did you solve the problem differently?
Posted By: lukester Re: 95 G30 Tow Project. - August 10th 2016 1:04 am
Looking good.
Posted By: Don_F Re: 95 G30 Tow Project. - August 13th 2016 12:52 am
On eBay, I was able to pick up a set of GM made 14 bolt SF 4.10 gears new and unused from 1982 for $75 and a matching VSSB from another party for $1.
The gears looked awful in the auction pictures, so much so that I and everyone else on eBay let them sit there for over two months. The seller said they were mostly just dirty from sitting on the shelf though, so I took a chance after another set arrived at my door step with some missing teeth courtesy of the USPS and a poor packing job. Fortunately this set arrived with just some minor dings and the gears were just dirty from sitting on a shelf.
Posted By: Don_F Re: 95 G30 Tow Project. - August 14th 2016 2:35 am
More progress today.
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Posted By: lukester Re: 95 G30 Tow Project. - August 14th 2016 4:12 pm
Nice. cheers
Posted By: lukester Re: 95 G30 Tow Project. - August 14th 2016 4:15 pm
Where did your mat?
Posted By: frscke1 Re: 95 G30 Tow Project. - August 14th 2016 4:24 pm
Yeah,where did you get your mat ?
Posted By: Don_F Re: 95 G30 Tow Project. - August 14th 2016 4:26 pm
Its thinner than the original mat, but its garage flooring and made to be driven on it should last a while. The original mat is so old it tears very easy.
http://www.homedepot.com/p/HDX-7-5-ft-x-14-ft-Diamond-Black-Universal-Flooring-HX45DT714MB/205442047
Posted By: Don_F Re: 95 G30 Tow Project. - August 14th 2016 10:05 pm
I am looking for some replacement upholstery for the two factory seats. Has anyone used this place? automotiveinteriors.com I hate ordering from unknowns, but van seat upholstery for older models does not seem that popular.
Posted By: lukester Re: 95 G30 Tow Project. - August 14th 2016 11:18 pm
Originally Posted by Don_F
Its thinner than the original mat, but its garage flooring and made to be driven on it should last a while. The original mat is so old it tears very easy.
http://www.homedepot.com/p/HDX-7-5-ft-x-14-ft-Diamond-Black-Universal-Flooring-HX45DT714MB/205442047



Thank you for the link. Looks like it has been given positive reviews.
Posted By: Don_F Re: 95 G30 Tow Project. - August 14th 2016 11:33 pm
Originally Posted by lukester

Thank you for the link. Looks like it has been given positive reviews.


No problem, glad to help. It was positive for me, its a 50lb roll of flooring that gets shipped cross country to the Home Depot for free. Its thinner than the factory mat but a lot tougher. The factory mat would just tear with your hands if you wanted to. It may be age, but it was at the end of its life. I kept the original sound deadening under the replacement mat. It was not perfect because of all the holes in the original mat, but I was able to patch it up. I think it's the same stuff GM used under carpet too.
Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2016 1:34 am
I added e-track mounts to a few places, I still have to repaint the seat risers, that's tomorrows job though.

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Posted By: maples01 Re: 95 G30 Tow Project. - August 15th 2016 4:01 am
Well 4.10 gears will not go on your carrier, get a limited slip while you are at it, if you had 3.73 you could jump to the 4.10 tho, the interior looks good, I got the luan and simply pushed and screwed it to the wall dry.
Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2016 12:56 pm
Originally Posted by maples01
Well 4.10 gears will not go on your carrier, get a limited slip while you are at it, if you had 3.73 you could jump to the 4.10


On the 9.5 the 4.10 and the 3.23 gears use the same carrier. The G80 I already have in there is in good shape and will do fine.
Posted By: frscke1 Re: 95 G30 Tow Project. - August 15th 2016 4:04 pm
I agree ....
Posted By: Don_F Re: 95 G30 Tow Project. - August 16th 2016 12:03 am
Just incase people get confused about if a carrier change is needed with a certain rear gear swap. Here is a link to great reference page.
Common Carrier Breaks at Randy's Ring and Pinion
Posted By: Don_F Re: 95 G30 Tow Project. - August 19th 2016 12:58 am
Trans pan temp sending unit. I welded the bung in the pan. I did this months ago, so far its worked well.

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Posted By: Don_F Re: 95 G30 Tow Project. - September 05th 2016 1:35 am
I took out the 3.23 gears and replaced them with the 4.10. The Eaton gov-lock was fine, so I reused it.
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Posted By: JIm Rockford Re: 95 G30 Tow Project. - September 26th 2016 12:47 am
did yours have the 4L80E trans? and did you have to get a new reluctor for the pinion?
I know when I messed with the old 94-96 caprices we had to swap in a correct reluctor when we swapped gears and change it in the tune .ohh and I always just screw the temp sending unit into a pressure tap port on the side of the trans .


Posted By: JIm Rockford Re: 95 G30 Tow Project. - September 26th 2016 2:15 am
Nevermind about the tranny question I reread your post and you said 60E , I would have figured a 1 ton would have gotten the 80
Posted By: Don_F Re: 95 G30 Tow Project. - October 15th 2016 12:43 am
For some reason I don't get notified when this thread gets a post. In 95 there were two main versions of the G30 and mine is the lesser of the two. I wanted a true one ton, but this one had only 106,000 and was pretty clean for the year so I went ahead and bought it. The lighter version has mostly parts from a 3/4 ton truck and a gvw to match, even though its a g30. I am really happy with the 4.10 gear swap and the OD trans. I have been driving it back and forth to work for a few weeks to break in the new bearings and gear set before towing anything and the mileage really hasn't dropped enough unloaded to be noticeable. The lower gears do help get the heavy van moving in city traffic. Freeway driving seems better as the engine doesn't have to down shift from 4th at the slightest grade like it was doing. The only other related change was the VSSB from a suburban with the same gear ratio and tire size.
Posted By: Don_F Re: 95 G30 Tow Project. - October 15th 2016 2:07 am
Originally Posted by JIm_Rockford
I always just screw the temp sending unit into a pressure tap port on the side of the trans .

The bung in the side of the pan makes a handy drain plug for service and takes the temperature from the fluid in the proper place. There is a lot of discussion on the internet about the pressure port being a poor place to mount the temp sensor on a 4l60e. I tried that first and it does read cooler on average. Since the factory seemed to think the pan/valve body was the best place to take the temp reading on the later 4l60e, I followed their lead.
Posted By: Keep_On_Truckin_WNY Re: 95 G30 Tow Project. - October 26th 2016 9:54 pm
Did you save the 3.23 gears at all...? Would you be willing to trade for a space set of 4.10's out of another 14 9.5...? I'm really thinking about steeper gears and an OD trans while I get my 5 lug swap all rebuilt...
Posted By: Don_F Re: 95 G30 Tow Project. - October 29th 2016 12:02 am
Those 3.23 gears are in the land fill, sorry. If you have 4.10s now I think you will be very disappointed in the 3.23 set. I have a 350 4l60e and even on very slight grades 4th gear would be kicked down to 3rd. If you don't have an OD trans I can see how you would want to switch though.
Posted By: frscke1 Re: 95 G30 Tow Project. - October 29th 2016 12:48 am
You would like the 4 56 even better. I have those in my 4x & 4 10 in the street machine....
Posted By: Keep_On_Truckin_WNY Re: 95 G30 Tow Project. - October 30th 2016 6:48 am
My van was built with 3.73, and at some point 4.10's were installed - yeah 350, Turbo 400, and 4.10 gears suck - 3,000 RPM at 65... I am planning a 5 lug swap (have a 10 bolt with 3.42's now) and hope to rebuild everything before it goes into the van, was just hoping for better gears while the swap was being prepared...
Posted By: JIm Rockford Re: 95 G30 Tow Project. - November 19th 2016 4:53 am
well the thing about the pressure port is the seals in the working part of the trans are what you are worried about, , the temp at the port is the temp of the fluid doing the work, so technically the pan even though it might be warmer isn't where the problem with hot fluid will start to cause problems, its the actual working temp of the fluid inside the trans the area where the seals are that really matters.
Posted By: Don_F Re: 95 G30 Tow Project. - November 19th 2016 12:50 pm
Thanks for the feedback Jim, feel free to use any location you wish on your own van. I did my research and for me after trying it there and talking to a local transmission shop about using that location, I chose to do it the way it is now. The one transmission shop told me in their opinion sticking a temp sensor there was more about measuring transmission case temperature and not measuring actual fluid because the fluid in that section is trapped until the engine is shut off and the pressure returns to zero. You will eventually see a rise in temperature, but like I said when I tried it, it seemed to be behind the temps I am now seeing in the pan.
Posted By: Don_F Re: 95 G30 Tow Project. - June 07th 2017 6:55 pm
I talked my mom into helping me sew some new upholstery for the van. Its not perfect, there are a few wrinkles that probably could be worked out if I wanted to add some more stuffing. I don't care and started putting them in as, its a lot better than torn upholstery with missing foam. The other seat is out warming in the sun before I hog ring it to the seat frame.

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Posted By: Dyno_Dave Re: 95 G30 Tow Project. - June 07th 2017 7:02 pm
They look good!
Posted By: lukester Re: 95 G30 Tow Project. - June 08th 2017 2:57 am
Seats look real good.
Posted By: Don_F Re: 95 G30 Tow Project. - July 13th 2017 1:52 pm
It looks like Photobucket account started blocking images. I can't edit my past posts to change the photo links to another account? If we can't edit past posts to fix this, there is going to be a lot of useless threads here.
Posted By: Dyno_Dave Re: 95 G30 Tow Project. - July 13th 2017 5:19 pm
Originally Posted by Don_F
It looks like Photobucket account started blocking images. I can't edit my past posts to change the photo links to another account? If we can't edit past posts to fix this, there is going to be a lot of useless threads here.


Great minds think alike. I just finished moving all of my photos to Flickr (fast, tons of free storage, love it!...should have done it years ago), but ran into the same issue. I sent ASTRO a PM this morning asking if there's a way to unlike older threads for editing. As soon as I hear back, I'll post what I find out. Otherwise, I'll have to build a "parallel" thread, and copy entries over to it.
Posted By: Don_F Re: 95 G30 Tow Project. - July 13th 2017 8:14 pm
I just checked out Flickr, it looks good! I will move my pictures there and empty Photobucket completely.
Posted By: Dyno_Dave Re: 95 G30 Tow Project. - July 14th 2017 2:28 am
I had two free accounts on the bucket, one maxed out on space, the other about half way. I moved all of them into a single account on Flickr, and have thus far used 1% of my allowed storage space.
Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2017 2:52 am
Yes! I was able to fix some ot the broken pictures. Flickr is the way to go now. I pulled the 4l60e and gave it some updates and a rebuild. Most of the updates from Sonnax went in along with some other items.
I made a giant clamp to hold the trans on my engine stand. I wasnt careful with the welds point and shoot as its only a 150lb trans.

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Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2017 2:56 am
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Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2017 3:00 am
Going back together I reduced the height of the cages about .060 after this shot as the height can sometimes keep the 3-4 clutch from applying with worn clutches.
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Sonnax HD 3-4 plates.
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Test assembled
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Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2017 3:06 am
Closer but needed an new washer to set endplay so apart it comes
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Working on the pump

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Sizing tool on the rings

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Almost done
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Converter #2 the first one went back as the dilbert's sent me one with a sanded hub.
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Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2017 3:08 am
The end of this part of the project. I drove it to the store and back a few times. It's all good. I will keep the trips short for a few weeks and pull the pan to inspect things later.
Posted By: Keep_On_Truckin_WNY Re: 95 G30 Tow Project. - August 15th 2017 5:48 am
Wow, have you done trans rebuilds before...? I have one in the m95 G30 Beauville I have, and I think I'm going to find one for my '90 Extended... they're plentiful, and can be built for strength, plus they're less of a power draw than a 4L80e...
Posted By: Don_F Re: 95 G30 Tow Project. - August 15th 2017 10:50 am
I have done a few, not many though. Maybe four or five. YouTube was my friend on this one. I was able to get the special tools off ebay, I still had a few hundred in those. I am not sure I would purposely search out a 4l60e, but since it was in the van and I didn't want to mess with the 4l80 swap. I did this. So far it's been a success, but since it's only been done for a day I have about 20 miles on it. The real test is if it lasts another 106K.
Posted By: Don_F Re: 95 G30 Tow Project. - May 04th 2018 6:37 pm
So far the transmission has done fine towing a 12x6 enclosed trailer and a Dyno Dynamics chassis dyno to local events. The stock tbi engine is a little under powered, but I can get to where I am going. One problem with the van is the factory mirrors when trying to back up the trailer. I even tried some plastic slip on mirrors for towing and the round bubble stick on mirrors and they are not much better. Even my friends who tow for a living can't see well out the mirrors once the trailer starts to angle. The factory mirrors are suitable for a non towing situation. The vans paint is very good for being 1995 paint, so I do no want to deal with filling the current mirror holes to bolt on another style of mirror. Has anyone tried adapting a camper style mirror to the factory base?
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Posted By: tuner4life Re: 95 G30 Tow Project. - May 04th 2018 6:46 pm
Those look like they fit pretty well! Do you have any info where they came from?
Posted By: Don_F Re: 95 G30 Tow Project. - May 05th 2018 1:53 am
Originally Posted by tuner4life
Those look like they fit pretty well! Do you have any info where they came from?

Maybe I wasnt clear, the black add on mirrors on there suck! I am looking for something better. They came off ebay and fit 90s Chevy and Dodge. They do fit well but that doesn't mean they are good towing mirrors. There is a small improvement but with a tiny mirror at the edge of the other tiny oem mirror its not that helpful. The round spot mirrors on the oem mirror made a much bigger difference. If you just tow on the freeway and never have the trailer at sharp angles they do fine. Once you start maneuvering the trailer at an angle, the end of the trailer goes past the edge of the tiny mirror and your jumping out to spot yourself a lot more than normal.
Posted By: Dyno_Dave Re: 95 G30 Tow Project. - May 05th 2018 2:39 am
Really. I towed with my '95 Chevy van and those slip-on mirrors for years. I had no complaints. Used the same concept of slip-on on my '94 Jimmy, with similar positive results.
Posted By: CatFish Re: 95 G30 Tow Project. - May 05th 2018 1:26 pm
We tow our travel trailer with our '95 G20. I've backed into some pretty tight spots with the factory mirrors, haven't hit anything yet. Our little trailer is small, only about 16' overall but it's almost 8' wide.
The problem I had was the door mounted spare and the trailer tongue jack were too close. Installed a removable mount for the jack and just take it off while it's hooked up.
Nice work on the transmission. Is your van hydra-boost or vacuum assist braking?
Posted By: Don_F Re: 95 G30 Tow Project. - May 05th 2018 4:14 pm
Those saying they had no problems with oem mirrors, don't get it. I already said it can be done, that is not the point. I HAVE done it for about 7 months now. Any late model towing vehicle already has mirrors that have a much better field of vision with an enclosed trailer and I am not the only one to notice this. So yes you may be able to back your travel trailer into a camping spot without any problem a few times a summer without noticing much. My situation is usually delivering a chassis dyno to local shops, weaving in and out of the customer cars in reverse through the crowded lot to get to service bay a few times a week. One of the hardest is a local shop with 4 mechanics working out of 2 bays, that lot is literally stuffed full and I have barely enough room to get in and out if they move some cars up the street. My original question was that if someone had adapted the larger rectangle sized mirrors to the standard mirror base. Not if it was possible to get by with the factory mirrors. I have the factory mirrors, so yes I know what I can see and what I have to keep jumping out of the truck for because I cant see. If anyone else is unhappy with the factory mirrors, like I said before, the round spot mirrors were a much better improvement than the slip on mirrors.

For the brake question. My van is the light duty G30 and it has some pretty good brakes over the smaller versions an its the standard vacuum assist. The trailer has four drum brakes too so that helps. The hayes g2 controller is what does a good job controlling them.
Posted By: CatFish Re: 95 G30 Tow Project. - May 05th 2018 7:20 pm
Point taken.

No I've never seen any OEM mirrors modified that way.

I did a search and ran across this slide outs:

https://www.centraltrailer.com/truck-camper-accessories/mirrors/74049-slide-out-tow-mirror.html

Don't look much different than the add-ons.
Posted By: tuner4life Re: 95 G30 Tow Project. - May 07th 2018 12:35 pm
While I haven't tried them out with a trailer yet, you could try swapping to the power mirrors from a conversion van. I'm not sure if the passenger side is convex or not, but I feel like I can see more area with the power mirror. And if nothing else, I can adjust it to where I want to see..

The stock mirrors you have are flat glass where most new cars have a convex passenger side mirror to see more area. While I haven't had experience with this personally, it looks like they sell a convex glass to go over your existing mirror glass. This may help your situation too.

https://www.amazon.com/1992-CHEVROLET-Convex-Passenger-Replacement/dp/B00NGOPAFW
Posted By: Don_F Re: 95 G30 Tow Project. - August 09th 2018 9:25 pm
I took the plastic extensions off. They do very little.

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I purchased a 2nd van today. 1974 G10. It was a good deal, I am not sure if It will stay or not. Paint is good but the mechanics need TLC. I came with a new set of 70s flares and air dam. Its a 3 speed on the column with no booster for the brakes. Not much fun to drive but I think with a little parts swapping it will be fine.

Posted By: tuner4life Re: 95 G30 Tow Project. - August 10th 2018 12:20 pm
Looks like a very clean starting point!
Posted By: newkirkinc1 Re: 95 G30 Tow Project. - August 10th 2018 12:42 pm
Looks great!
Posted By: Don_F Re: 95 G30 Tow Project. - May 04th 2019 4:21 am
Its been a while since I updated this. Over the winter I removed the swirl port heads and flat tappet cam. I replaced them with Jegs crappy imported vortec heads and a baby 196 duration Chevy 14097395 cam. The idea was not a race car, but more grunt where I needed it for towing a 5000 lb trailer with a 5000lb van. The heads are a long story, but they will do. The cam I can't say enough good about for towing. It required a re-tune on the chip, but it tows a lot better. The left fuel table is the stock one the right is what the engine requires fuel wise with the new setup. The crappy low end on the left is now a big hump in volumetric efficiency, more air and fuel at low rpm, but I don't have to floor it all the time, so it works out gas mileage wise. All this is a few months old and the fuel table is more refined now.

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After all that I couldn't have it dumping through the rusted exhaust so I bought a few stainless sections from summit and did a budget exhaust that should last a while.

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The before and after dyno sheets Dyno Dynamics does not calibrate their readings as high as the USA made Dynojet, the comparison HP is what is close to the DJ numbers. The columns are in different orders on each sheet, and I started the "after" pulls at a lot lower rpm to see if I lost anything down low. A 40hp gain on the top and a 50ft lb torque gain across the whole torque curve made a big difference. The engine still tops out at about the same RPM and that's fine. I don't run it above 4000 when towing anyway, mostly in the 1800 to 4000 range. I did some more work on the fuel curve since these runs were made, but have not put it back on the dyno. Its still breathing through cast iron manifolds and the factory TBI. It still idles, runs and sounds like stock, but in the way GM should have done it instead of how it came off the assembly line.

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Posted By: frscke1 Re: 95 G30 Tow Project. - May 04th 2019 4:51 am
NICE ! !
Posted By: Dyno_Dave Re: 95 G30 Tow Project. - May 05th 2019 12:34 pm
Glad you came up with a combo that works for you Don. Congrats!

Would you mind sharing what the issues were withe the Jegs Vortec heads?
Posted By: Don_F Re: 95 G30 Tow Project. - May 05th 2019 1:23 pm
The Jegs heads were originally advertised as having bronze guides and high lift springs. One I got had the high lift springs but no bronze guides. I was in a hurry so I painted it and stuck it on. The second one was the same casting but from a different manufacture. It was damaged. I asked Jegs to send me one that at least had the high lift springs like the first. They had just switched suppliers. No bronze guides as advertised, no high lift spring. A stock Vortec cam would be very close to coil bind. Very sloppy machine work. I asked if I could return, but they would only take the one that had not been installed. My fault, check both heads before painting or bolting anything on. I ended up removing the installed head and installing a new set of springs and retainers on both to get the proper lift clearance. With these heads the castings are pretty good, thick casting so there should be no worry about cracks like with GM heads, its just the machine work is super sloppy. The last version of the vortec heads from GM are a hit or miss too. Some say the castings are revised without notice and the exhaust ports are raised compared to the bolts. This causes standard exhaust manifolds to block off part of the port unless you grind out some of the roof. Jegs was worthless, they would not even remove the bronze guide description in their ad. After I harped on them for a month they finally took one apart and then suddenly the ad was changed.
Posted By: Dyno_Dave Re: 95 G30 Tow Project. - May 05th 2019 1:44 pm
Thanks for the details Don. I have no agenda, I just wanted to know facts from someone who's been there and done that.
Posted By: Don_F Re: 95 G30 Tow Project. - July 09th 2019 12:18 am
I gave the van a real towing test a few months ago. I got called to tow the dyno to a small town in middle Oregon. Only about 80 miles each way but its in old volcano areas. The highway is straight up and down. The engine torque from the upgrades is noticeable it did fine. I went over the truck scales at very close to 10,000 lbs total. The problem was the trans temp. I had to let off on the steepest parts as the temps were going to cook the trans. I had the factory trans cooler as an option. One person told me there is a bypass built in and its a poor design. After many miles the bypass tubes work better than the other tubes and not much cooling gets done. I sourced another cooler from TruCool. They made the original too, but this one is twice as thick and has no bypass so it all has to go through the cooler. B&M Supercoolers are re boxed Tru-Cool coolers. I went with the Tru-cool box since it was less than half price. It was pretty easy. Since the same manufacture one side of the bracket was perfect, the other side needed a square piece of sheet metal. I had to trim the grill a bit from the backside because of the extra thickness. I have not pushed the trans that hard locally but it seems to cool better. There is one area where the factory add on trans cooler line has a necked down area to slide into the main cooler line. I think that may hurt cooling as well. I have not cut that out yet but will if trans temp continues to be a problem

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Posted By: kursed Re: 95 G30 Tow Project. - July 09th 2019 12:26 am
Lookin' good! cheers
Posted By: Don_F Re: 95 G30 Tow Project. - July 17th 2019 2:42 pm
I set up the dyno in my driveway on Sunday. Just to fine tune the fuel tables a bit. My neighbors are mostly nice about it as long as I don't do it too often. The second picture is last years beginning pull with an open air cleaner and the under drive pulley. Compared to the Vortec head swap, tiny 196 duration roller cam, and better exhaust system. It still uses the TBI and the stock exhaust manifolds. Its still a truck engine, it runs out of breath about 4000 rpm but the huge increase in torque over the stock engine helps a lot when pulling 10,000 lbs of van, trailer and dyno around. There is some differences between the runs, In the last runs I locked the converter early and locked it in gear to prevent the converter from locking mid run. I also used a mathematical ratio to figure rpm and its slightly off. Its not a big deal, but its a difference when comparing the two. Mostly the runs where to dial in the fuel table, for that you just need load and a wideband. The runs were just for information at the end of the work.

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Posted By: kursed Re: 95 G30 Tow Project. - July 20th 2019 2:13 pm
Definitely a healthier pull. Awesome work man.
Posted By: Dyno_Dave Re: 95 G30 Tow Project. - July 21st 2019 12:18 am
Looks great Don! Nice work. Wish you were here in Michigan...I'd set you loose on the TBI 305 (L03) in my Trans Am.
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