Have a couple questions hoping maybe someone can help me with I have a 69 Bonneville that someone put a 79 firebird 301 in look ls as they made some adapter plates to get engine to mount To factory frame location but I?m not sure I have built several 66-68 impalas this is my first b body Pontiac.I?m gonna pull the 301 out and the 400 trans and put a Chevy 283 in for now to get it running and moving on it?s own again.I don?t see any small block engine mount holes on front crossmember did the pontiac b bodys have a different front crossmember/frame ?
The Pontiacs built in the United States have an entirely different chassis than the Canadian Pontiac. The Canadian Pontiac uses the Chevrolet chassis and floorpan. There wouldnt be any holes in a US built Pontiac for mounting a Chevrolet engine as they werent used in that application.
I assume this is similar to the problem I went through when I put a 455 from a 1975 Laurentian into a 1964 Tempest/Lemans/GTO body? If I bought 64 GTO mounts, they wouldn't bolt on to the 455 and if I used the 455 mounts they didn't fit the 64 chassis.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
Awesome thanks for all the replys appreciate it.cars pretty tough was hoping to get it moving under its own power to get it to body shop and start tear down then was gonna worry about doing a better drivetrain setup.at this point I think Ill just toss one of my ls engines in seeing as Ill have to do same amount of work to put a sbc
By the way me and another friend drove that car from Florida It actually had 2 428 Pontiacs in it when it crossed the border We pulled one out of a 69 GP and the loaded it in the back
The challenge with a chevy engine in that car is that unlike the A or F bodies or even the 71-76 big cars the 65-70 that all use corporate GM frames the 65-70 big cars all had their exclusive frames with no sharing between divisions. If you want to put a chevy engine in say a 69 GTO you just get a set of chevelle engine mount brackets and they bolt in to the frame because all A bodies shared frames across divisions. But a pre 71 big Pontiac has a frame that was engineered to receive only the pontiac engine. Chevy mount brackets won't fit and the cross member (pontiac had two in the engine bay) may be in the way of the chevy exhaust dumps. You can always make it fit but it will be a pain and a butcher job in the end. A Pontiac 400 or 428 would be easier, cheaper and add rather than detract from the final value of the car.
I understand what youre saying with Pontiac engine in a Pontiac.unfortunately this car was devalued the day the 428 was removed and air ride put in it. The guy I got car from was taking about scrapping it be cause several people looked at it and didnt want to try to fix the rust.it needs floor pans and roof patches not the greatest car after sitting in the grass for years but i wanted to do something with it.Id need engine and trans for pontiac and for the price of Pontiac engine I can put in a fuel injected 5.3 I have with a nice setup for a decent driver to enjoy the car again.its missing a lot of pieces that Ill still have to track down like bumpers and fenders but this is a driver/toy not really Im confident in my abilities to use the ls drivetrain and not hack or butcher the car anymore