Engine SwapEverything about swapping an engine into your Third Gen.....be it V6, V8, LTX/LSX, crate engine, etc. Pictures, questions, answers, and work logs.
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But if I may be so bold, it's not a big block; it's a Pontiac motor. Not that the block isn't big; it's just, there's no such thing as a "big block" Pontiac. Either it is a Pontiac motor, or it's not a Pontiac motor. The bore spacing (the thing that sets a "big block" apart from a "small block") is the same on all their motors; even the little 151 4-cylinder has the bores on the same centers as a 455.
I see you still have the exhaust manifolds on it. What are you going to do for exhaust? Any idea how long it might be before the rest of it is hooked up and running?
__________________ "So many Mustangs, so little time..."
as far as you being bold, i dont mind. to be honest, i know nothing about pontiac. and even less about chevy. i am a ford guy. but, the motor and the car landed in my lap so i ran with it. i had purchased headers for it thru pontiaction racing but they didn't fit correctly. so my buddy gave me these maniflods, which he says are off of a early 70's GTO. they dump in the same location as the 350 i pulled out. i was thinkin of getting a cat - back system and havin the local muffler shop make something up to conect them togoether. the motor is running, the car is not .. lol. i have to redo the brakes( complete ). get a driveshaft made. the interior is completely gutted. i am guessin in a month it'll be on the road.
Originally posted by RB83L69 Looks good so far....
But if I may be so bold, it's not a big block; it's a Pontiac motor. Not that the block isn't big; it's just, there's no such thing as a "big block" Pontiac. Either it is a Pontiac motor, or it's not a Pontiac motor. The bore spacing (the thing that sets a "big block" apart from a "small block") is the same on all their motors; even the little 151 4-cylinder has the bores on the same centers as a 455.
It is a big block Pontiac, because the 301 Pontiac was smaller than all the rest of the Pontiac v-8's
The 301 has the same bore spacing as all the others. In fact, the 151 4-cylinder I mentioned, is half of a 301. That's the "Iron Duke" POS.
However, the 301's deck is lower than all the other V8s; so it's a "short deck" block.
Kind of like big block Chevy motors. There's small blocks, and there's big blocks; within the big block category, there's short deck motors (passenger car and pickup type trucks) and tall deck motors (larger trucks like buses and dump trucks). Or Oldsmobile; every one of those has the same bore spacing, but the 400 & 455 have a tall deck, and the 307, 350 and 403 have a short deck. Again, no "big" or "small" blocks.
There are no "big block" or "small block" Pontiacs.
__________________ "So many Mustangs, so little time..."
i used their mounts. the headers, first of all, were in my opinion poorly made. i am a machinist and a part time welder and i could have done a better job welding the flanges. who knows, maybe i got the only bad set they have. second, they hit on the lower motor mounts and crossmember and the frame rail on the passenger side. now i would have no problem working with the headers and making them fit. but, i paid over 500$ for something that wasn't coated and didn't fit. HELL NO! lol
omg , sweet , i want to do that . I looked into it , what kind of project was it. I love it . Hey , chiefmanyhorses.com sells headers and motor mounts that are meant for a thirgen with a poncho engine. What kind of tranny did u use. And what kind of problems did u run into .
i am using a 77 th350. the only real problem i had to deal with was moving the trans mount back about 3.5" and needing the driveshaft retubed. needs to be about 5.25" longer. other than that.. i had to make my own radiator brackets and the rest is off the shelf stuff. i put a torque arm on that mounts to the floor and not the trans, it's 1/2 the length and is supposed to be better for wheel hop. with the pontiaction racing mounts there is enough room for a small oil filter. the exhaust manifold exit in the same location as the originals from the 350 chevy. all in all ... it was an easy swap. just takes time.
i looked into the spohn torque arm kit ... but i spent 160$ for the jegster torque arm and made my own braket for the trans.i did not have to do anything to the trans cross member. you do the math .. lol:rockon:
i went with what i had .. i have decided that this car is going to be my test subject. when i have completed it i will know exactly everything i need to do the swap. then i can search for the permanent car. who knows... could be a fairmont .... lol.. it all depends on what i like at the time .
IIRC, the originally Pontiac Firebird 455s (about 1970, etc) were a bear when it came to spark plug changes. Something like, loosen motor mount, jack up engine, contort hand and arm into bizarre shape and go from there.
lol... this was my first motor swap of any kind and i thought it was very easy. gut the computer and it's harness. use the remaining harness for the rest of the hookups. the wires are already there. hell ... use the stock dash if you like. i used auto meter gauges myself. all in all... 160$ for the tourque are from jegs. 80$ for the motor mounts from pontiaction racing. 275$ for drive shaft mods. a couple of home made brackets, which anyone whith a 9th grade education should be able to figure out, and it's in there. no fuss no muss!
I like this swap,now just add EFI and a 6speed and that thing will haul the mail..................this is the way things should have been done at Pontiac....Good job:hail:
its sweet, so props to you. Another F0RD guy converted from the dark side! Muwahahahaaaa!
-G
__________________ Silly Honda Kids, r¡ce is for Uncle Ben! "A little pain never hurt anyone."- Me
"a carb can give 500hp easy,,you just need cubic dollars....the aussie"
i'll tell anyone who wants to know exactly what i did. what brakets i made and the dimensions for them. it's well worth the time .... the money got a lil out of hand ... but it's all motor and trans money. but hey .. if your gonna do it ... do it right. don't half *** it. with close to 500 h.p. and well over 500 ftlbs of torque... i think this car is gonna get some looks. lol.
I'll take you up on that offer. I was origonally gonna put a 400/400 combo from a 76 Bonnie into my ride, but then I wouldn't have any car to drive durring that time, and had no place to do the swap
__________________ Giving the enemy the opportunity to die for their country
Originally posted by Parrydise7 IIRC, the originally Pontiac Firebird 455s (about 1970, etc) were a bear when it came to spark plug changes. Something like, loosen motor mount, jack up engine, contort hand and arm into bizarre shape and go from there.
Are you looking at the same thing?
poncho's are one of the easiest cars to swap plugs in, they were smart like oldsmobile and put the spark plugs on top of the exhaust manifolds unlike some other GM division, chevy cough cough chevy
Originally posted by RB83L69 There are no "big block" or "small block" Pontiacs.
It's a common misconception. I think most enthusiasts, when comparing the Pontiac engines to the small block Chevy engines, are correct in saying that it's a 'big' (fat) block (again comparing it to small block Chevy's).
But when comparing them within it's own family line, then yeah.... there's no such thing as a 'big block' Pontiac.
RB83L69, do you remember a long time ago when some 'guy' named Mickey Thompson had developed a Hemi headed Poncho? Why they didn't capitalize on that concept, I have no idea.
AWESOME swap! Looks great. I kinda wish I would've done what I was planning for my GTA.....
Poncho 4XX ci stroker
edlebrock aluminum heads
aluminum carb intake converted to EFI
stock TPI computer and harness with lots of tuning
aftermarket headers/motor mounts
6speed or 200r4 behind it
12bolt/9" rearend
*I really wanted to do it and I got tired of people saying not to mess with it, but I'm a diehard Pontiac fan and out of the 3 Ponchos I own.... only one of them is Poncho powered.
Instead of this swap, a totaled LS1 TA fell into my hands and the rest is history.... for now. I will do a Poncho powered 3rd gen bird one of these days. Its a for sure future project. Congrats on attempting and pulling off the swap. Absolutely awesome! You better post ETs when its done!
__________________ '99 TA 'vert: LS1/A4/2.73's, 11's/315's out back, Borla & SLP lid, my current DD. '91 GTA: LS2/A3/9", 645RWHP, 9.98 @ 135, my old DD. -Jeremy-
i did this swap a few years back. i wish i would have kept the car. it was an 82 Trans Am and i had the Poncho 455 and a T400 tranny. but to be honest, my friend and i did it and we just pretty much rigged things up to make them work instead of the proper solutions, but it DID work and it was FAST. do you have handling problems with yours now? i know i had all kinds of new handling problems, just from the added weight in the front end. looks like you did a REALLY clean swap looks good! do you have a cowl hood to go on it, or is that next? you got any pics of the whole car? it looks like that yellow color that came factory (proper name slips me at the moment, im on narcotic pain killers, whaddaya want?) that was pretty freakin rare. what you got for an axle? i had a 10 bolt with a c-clip eliminator kit, 3.73 gears and a worn out posi, . have you got a shift kit at all? i always wanted one but i sold the car before i put one in. my friend i sold it to wrecked it and damn near killed himself a week later! but again, NICE swap!!
Josh
__________________ "EVERYTHING IS NOT A CONSPIRACY!!!"
On F-Body #6...
1988 Camaro
LO3, 700R4...will post mods as it gets 'em!
first off, Projek: 85 3800, i haven't forgot about you. just been sick. second, i have not had the car on the road as of yet. i spent to much money on the motor and trans(bout 4000$ give or take). now i am at a crawl with this thing. i still need a driveshaft made up. and i cant seem to find anyone in my neck of the woods who'll re-tube it for less than 300$. seems a bit expensive, but what do i know? the trans is a th350 with a b&m shift kit. b&m 2400 stall converter. racing sprague gears and kevlar bands. the rear axle is stock limited slip. i'll probably find out that it is shot the first time i lay into this thing. the car looks liks crap and i have decided that i am not going to put much more into it since i will be looking for a formula or a gta to put the motor in come next year.
That sounds a little steep for a driveshaft...the last one I had made (steel) was about $150-175 I believe, but that was about 10 years ago too. Still, I would think even a custom aluminum one would be not much more than you quoted, so steel should be less. Worst case, you could do some salvage yard scrounging and try to find one the correct length.
yeah ,,, i should have kept the driveshaft out of the 77 trans am that i junked. i think that might have worked. it was only 1/2 shorter than what i need. should have been ok. i say" should have been" lol.
i just had a 400 fall into my lap. since it was "free" (i traded some 14" BFG's i cna't use anymore for it) i wanted to know if you can stroke a 400 poncho to get 455..... or if I'm stuck with a 400 CID. any thoughts?
yes i think the most you can stroke a 400 is to 467 or something around that size, but you can stroke it to a 455 but you have to bore it out (if i remember right 60)
Hey flyitlikustolit, a 400 can be made into a 455 by one of two ways, 1: buy and aftermarket crank with a 4.21 stroke and 3" mains or, 2: accuire a 455 crank and turn the mains down from 3.25 to 3.00". but you would have to use special bearings for the second choice. As for pistons, if your block is standard bore, all you have to do is bore the block out to standard 455 bore specs and use standard pistons.
P.S. If you dont plan on using the 400 for anything, I'll gladly take it off your hands. I live in Dallas , Ga
Daryl
oh no, i plan on using it, whether it's a 400 or a 455 in the end. what i'm making sure is that you can A) bore it that big safely , B) find an aftermarket or OEM crank to provide the right stroke. any help would be great. in fact, just lay it all out for me. bearings, pistons, rods, cranks, dimensions, anything and everything you got. I'm trying to get 455 CID out of this 400 CID block i have. what do i need to change to accomplish this? it will probably get a rebuild, so machine work is not a negative point. also, I've heard 6x heads are good. is that what i should try and get? i think these heads are from a GTO, so they're probably 6x right?
I saw a nice 82 TA at the TA nats with a 400/Th400 in it last weekend. The owner said he used late 70s Pontiac block mounts with the original frame mounts. It also had RAIII manifolds. I think Redraif got pics of it, so I'll get her to post them.
Originally posted by flyitlikustolit I've heard 6x heads are good. is that what i should try and get? i think these heads are from a GTO, so they're probably 6x right?
If you go looking for a set of 6X heads, try and find a set of 6X-4's(91cc chamber) instead of a pair of 6X-8's(101cc chambers). The 6X-4's will give you a little extra compression.
Several companies sell the correct cranks and also rotating assemblys to convert the 400 to a 455. One is Jim Butler in Tennessee (?) and the other is Kauffman racing in Ohio. Both are very helpful and knowledgeable about Pontiac motors, and have both run in the 6 sec range in Pontiacs.
There are other engine builders, too that are Pontiac experts, but those are the fastest two. Check out High Performance Pontiac magazine (They have a website www.highperformancepontiac.com) and get ya an issue. It is full of good stuff on not just Pontiac motors, but 3rd gens, 4th gens, new GTOs, old GTO's and everything you can think of. I just can never find it on a newsstand.
Also, Pontiaction racing, cheifmanyhorses, and Indian adventures are all the same company, and I have never heard anything good about what they make.
) 
Silly Honda Kids, r¡ce is for Uncle Ben!
"A little pain never hurt anyone."- Me 
