Hey guys...so i have a question:

I was wondering if you guys could help me with something that i'm not sure about. And before you say anything, i know it sounds blasphemous, but stay with me.

I have a 1981 Pontiac Trans Am, and I'm swapping the original 301 turbo pontiac motor for a sbc 383 stroker. now i'm aware that the subframes for both the camaros and trans ams of 1981 are the same, but do i need to do any modifications to the motor mounts/engine mounts? Do i need to weld on adapter plates or something to the subframe? any knowledge on the subject would be greatly appreciated!! thanks

 

Not any welding that I know of, but may need the frame mounts from a 2nd gen Camaro to bolt to your subframe. Or may need to relocate yours to match. I'd probably do a test fit with the factory mounts for the SBC to see how they align, and then if they'll work with a relocation.
Blasphemous? Not by my standards. But I have no standards since I have a '63 Falcon with 464 BBC, and '46 Austin with 355 SBC!

 

I must agree with 197BB427 thinking. People should but a small block into every thing. Slowpars and Fords could all use the help in the performance department. Stuck a simple vortec truck motor with a cam in a mustang and went 12.20 at 109.8mph in the quarter. Ford guys on the mustang site went ballistics with ideas that if I stuck $6000 into the ford motor it would run that fast to. Heck I don't think I had $500 in that motor. That 301 turbo motor from Pontiac was a real piece of work, I don't think I know of any body that made it work. Use it as a sailboat retainer.

 

You are aware the Pontiac has a different transmission bolt pattern then the chevy? You are going to need a chevy trans.

455 would bolt right in. Just sayin Course the 301 trans would last about 3 pulls in either the 455 or the 383 anyways

 

Actually the Pontiac trans will bolt up, but two bolts wont line up. There have been several articles over the years on how to redrill or make the BOP trans work with a Chevy V8. If you have a high HP SBC or BBC I'd get the correct trans bolt pattern, but the reworked trans will handle 350 hp without worries.

 

One thing about GM they did not waste money. If a turbo 350 was going into 180 HP car it got clutch packs that could handle 180 HP. Pulling out a transmission drilling it out and rebuilding seems to me like a waste. Just get a chevy one.

 

I did get a muncie rockcrusher 4 speed along with the motor, so no worries there. However, the car is currently an automatic and I'm wondering how much modification i'll need to do to the firewall/transmission hump to get the manual working right. I'm also getting the linkages, driveshaft, shifter, and everything else except for the pedals. After that, i'll just need to finish sandblasting my suspension parts, redo my brakes and fuel lines, and i'll be good to go!

 

Shouldn't be any firewall mods needed. There should be a blank over the clutch rod hole that will be removed when you install the pedal assembly, and you'll need the rubber boot to go over the hole. You'll also need a pilot bushing for the crankshaft, and a pivot ball for the block, plus the Z bar linkage for the frame to engine pivot ball.
Hopefully you'll get the entire 2 pedal clutch/brake system, as the automatic has a wider pedal that wont work. The hump will need a hole for the shifter, and if you want it to look "factory" there's a sheetmetal piece that needs to be added to the hump to make that look work.

 

I have always wonder. Are all small blocks prepped for the pivot ball? I never really looked and when I think about it I never have a gen one block around.

 

Even the last of the gen 1 casting still have the pivot hole drilled and tapped. I work with the 880 vortec casting from 96-2001 be for the LS truck motors and they are all tapped. If you wanted to install the vortec motor in a 55-57 chevy with the front motor mounts, those holes are also their.