Pontiac 400 in a 1967 Chevy C20
 

I am working with Justin on yet another project. It's a 1967 Chevy C20 fleetside long bed. Original engine is a 283 with 3 on the tree. We have the truck completely apart and have sent the rolling chassis off to be bagged. See link.
http://67-72chevytrucks.com/vboard/s...d.php?t=252362
Meantime the body has been media blasted and is awaiting the frame.
We are discussing engine/trans combinations. We want this to be a driver truck with balls. It will also be used as needed as a tow vehicle. Having said that mileage is a factor. There are a couple choices that come to mind right off.
1. Rebuild original 283 and upgrade to 700R4 AT.
2. Drop in a Pontiac 400 (which we have in garage) and upgrade to 700R4.
What thoughts, feedback does the board have? If anyone has planted a Pontiac in a Chevy truck please speak up.

it's a pretty easy swap. i'd use the pontiac for the torque, drop the gears to a 3:08, 3:23, 3:42 and use a 3spd auto or a manual 4spd with grannie gear.

decent milage, good torque and an easy install.

mike

I sold a GMC to a friend that put a 400 in it. He used a turbo 400, but didn't tow with it. I would suggest, if possible, put a manual behind the 400 for towing. Autos don't like the heat associated with pulling any kind of weight. Example, Another friend had to leave his fifth wheel travel trailer near the top of Turnagain Pass when his auto transmission puked and he had the truck towed to town, then get me to go get the trailer.

I have a 71 C-10 2wd that I have had a Pontiac motor in for years.I used to have a low comp 455 with 3.73 gears and you didnt even have to open the secondarys on the mountians towing with it.I now have a 77 Gran Prix 350 in it which has been used for towing for 3 years.It is bone stock with just an old 70 iron Q-jet intake-headers, a 400 turbo and 3.42 gears.I have an open trailer that I tow with and just this year I bought a 20 ft.enclosed trailer that I haul my Trans Am race car in.I made my own motor mounts but it is a fairly easy swap.I love it and it gets more attention at alot of events that my race car.The 350 is getting a little tired so I plan on a 455 swap back in this winter.The truck ran a 14.52 in the quarter with the 455 years ago-thats thru pipes and with slicks.It was just a 73 455 with 068 cam, 76 6h heads to keep comp down to run on todays s__t gas.It now runs 16.2 with the 350 and has filled in a few racing rounds in the Outlaw Pontiac Drag series last year when my race car broke-you are allowed to run a pontiac powered anything.It just tows fantastic and I cant say enough great thing about the swap.You will be proud to open that hood when you get it finished-I say do it!!!!Let me know if you have any questions or I can help in any way.I can send you pictures if you like.Good luck.
Shawn Miller

Guessing that he is having the truck "bagged" I don't think there is much towing in that trucks future: Bagged = air suspension installed, as in lowered sport truck. I wonder if there is a body drop in that trucks future as well.

I don't think you can get a 700r4 to mate to the pontiac block. I know you can get a 200r4 though and a gran nation spec one should be able to take the output. There may be an adaptor out there for the 700r4 but I don't know about it.

I like pontac motors over chevy because the low end grunt is much better. MY GTO's 400 always had a better 60ft time than my chevelle's 396 (ok '72 402 in a 67 body) and it just feels torquey.

Because of heating issues I would keep the 400 close to stock as possible, no supremely radical cams, just a good intake and carb, mild cam, headers or ram air manifolds, and a good ignition should have you at the 400 ftlbs mark and close to 400 hp.

one thing is for sure you will have something really different. Personally, to me pontiacs look the best with multiple carbs, and there are plenty of tri power and dual quad manifolds in the aftermarket.

Yes, there are Pontiac-to-700R4 adaptors- my Suburban has one. Dave Anderson- 'Big Injun' screen-name- could tell you where they got it.

Yep....adapters are available.
I have a buddy who has a 700R4 behind his 464 in his 63 GP...
Runs great...
He'll be at Norwalk this week if your'e there..shooting for 12's....

Been thinking about doing this swap myself.....
 

.....to replace the tired 402 BB in my '70 C20. If I do it I will run a Pontiac 350 to try to get better fuel mileage, currently getting 9 in the city and 11 on the highway driving 60-65 MPH.

I'm sure any Pontiac 350 in good running order will out-torque my tired 402, my truck has a 4.10 DANA 60 rear and a TH400.

Trans-Dapt adapter for the 700R4 trans to Pontiac block:http://store.summitracing.com/partde...1&autoview=sku

Thanks everyone for the feedback and encouragement. This is one issue Justin and I are not in agreement on. I really favor it and he doesn't. I think I'll leave it alone for a bit.
Good news is the chassis work is coming along smoothly. A local guy doing the work for us is posting pictures of the progress. I'm pleased. Check it out.
http://67-72chevytrucks.com/vboard/s...97#post2300897