73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: txtj79 on September 14, 2008, 08:14:13 pm
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I have a chance to buy a good 350 longblock out of a '71 Firebird. I plan on putting it in a '78 C-10. Is there any difference between the block and a chevy block?
Thanks,
T.J.
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Completely different if it is a pontiac 350. Are you asking if it will bolt in?
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(http://www.mccollumracing.ca/images/luke's%20motor%20copy.jpg)
(http://images.chevyhiperformance.com/thehistoryof/0605ch_11_1970_small_block_engine_z.jpg)
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TJ, Beyond the numbers 3 5 0, they have little to nothing in common (assuming the Firebird still has a Pontiac engine in it). Lorne
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ok, that's what I needed to know.
Thanks,
T.J.
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dont rule out the fact that the firebird is now 37 years old and could very well have a 350 chevy swapped in.
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The nice part is if you do the Poncho swap, trading up to a 455 later on is a simple bolt in, since they are identical motors. Buick, Pontiac and Olds were interesting that way: they all used 1-size block for small to large displacement.
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Only the Pontiac was like that. Buick and Olds had short and tall deck engines.
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The other difference is that the bellhousing pattern is different from chevy's; So you'll have to get an adapter plate or get a different patterned transmission; Buick, olds, and pontiac(also cadillac) have a certain transmission bellhousing pattern----so here's where the term, B.O.P. came about. Chevy
and cadillac share the other pattern. Why GM did this, i have no idea.
Another thing is that the frame mounts may have to be changed or the brackets that attach to the engine may have to be changed in order to install it in the truck's chassis. i will attempt to do some research on this if i get the time.
Pontiac v-8's (from what i've heard?)tend to have more lower end torque while chevys dominate middle and top end? (i think?)
By the way, i love all GM engines even cadillac's.
i love them in this order:
1 chevy
2 pontiac
3 gmc
4 detroit diesel
5 olds
6 buick
7 cadillac
i think a possible advantage to pontiac engines is that since no-one wants them, you can get them for cheap or next to nothing or possibly free.
Here is an excellent video clip for anyone into pontiac/pontiac engines:
http://jp.youtube.com/watch?v=hg4QtYizPKM
i would say definitely go for it.
NOTE: 9/17/08 mr. Lorne corrected me on the BOP trans pattern---cadillac also shares it.
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A couple of guys on here (Lorne aka Haulinit and Uno99) both use Olds motors. Lorne has a 455 Olds that puts his truck into the mid-12s. He told me how he did the mating of the motor to the stock Chevy mounts and it doesn't seem that complicated.
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Stew, The Caddy's are the same bell housing as the BOP, Chevy is all by itself. Just want to keep everybody on the right page. Lorne
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Further to that, that only applies to the 472 and 500 motors. The 429 and down had their own thing going on. The 66 Caddy hearse I have has a 429 with a TH400 "Switch-Pitch" tranny that basicaly has no more reverse and I think has given up on 2nd and 3rd gear. Replacing with it with anything but the same was not possible, so only a rebuild can be done and that's apparently going to be $1000 :(
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Bah, you can rebuild that sucker for about $200 bucks. If it is a switch pitch hold on to it provided no one ever replaced the torque converter.
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Stew, The Caddy's are the same bell housing as the BOP, Chevy is all by itself. Just want to keep everybody on the right page. Lorne
Yes, you're right. i must have mis-read or something? Maybe chevy and cadillac share the same internal gearings or something? i know they share something that BOP doesn't.
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Bah, you can rebuild that sucker for about $200 bucks. If it is a switch pitch hold on to it provided no one ever replaced the torque converter.
Yeah, typical quote from the tranny shops around here that just like to soak people for everything they got. I think that's an interesting idea with the whole switch pitch thing. Kinda like a high and low stall converter built into 1 eh? Must not have worked well or who knows since they didn't offer it very long.
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It just effects the stall speed of the converter to increase torque multiplication.
The tranny shop isn't trying to soak you. I would charge a customer off the street about the same. Time, parts, electricity, shop supplies, employees, insurance, uniforms, yada yada yada...it all adds up... no one works for free. You can probably find a guy local that will do it on the side for you for $400 ish
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Sux, Yea, I hadn't really gave those engines any thought, that is odd, you figure in '66 BOP were allready what I call the "normal BOP" & they were making the TH400, why the weird bell housing? Was it left over from prior Caddy engines, say '62-'64? The 425 & even some of the newer 366(?) also shared the same bell as the "normal BOP". How far back do we have to go to find the beginning of the "normal BOP"? Did the '66 Buick 401 have it? Anyone? Lorne
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As far as I know, the 429 Caddy was the last revision of the 390 V8 that was used since the mid-50s. The 472 and later 500 was a new engine. Nice motor though. Back then, Caddy was doing different and better engineering it would seem. That 429, now with a rebuilt Rochester 4-Jet, fires up on the first crank every time and runs smooth and quiet. Not bad for an engine that doesn't see regular use and has probably been neglected more than anything else in the past 20 or so years. 340 gross HP, 450 lb-ft of torque and 10.5:1 compression too.