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.
Welcome to ThirdGen.org!
Welcome to ThirdGen.org.
You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!
i duno what the hell that guy was saying about the thread not having info on the swap? i only have one thing to say to him INCREASE YOUR MEDS! instead ranting and raving take a hour or two and read! i'd like to thank of you guys for your headaches you had and the hours and hours you have spent gving me this insightful information. my only 2 questions that remain in my head are. stock ram air 3's seem to be the ticket for exhaust manifolds, does the rest of the exhaust system have to be fabricated? and do the engine mounts still exsist? this is dated october 18th 2008...woofy
hi im doing an 455 engine rebuild for my grad project and i was wondering if i could put the 455 in an 80's trans am or iroc? also how much would that kind of project cost?
hi gary
the project your taking on isnt all that hard to do. the 80 transam is your best bet, if it had a 301 pontiac v-8. the pontiac engine family is simular in mounts from 326 to 455. the 301 i think is different. the bad news is the 1980 trans-ams enigine were reduced in size from the 400 used in 1979's to the 301. the good news is the 400 mount (both lower and upper mounts) mount in the same position and absolutely fit with very little difficulty at all in the 80 and 81. the 455 is the same as the 400 block, just make sure the block if its a 400 is post 1970 , or you will need special adapters to fit a "68 400-428 block to a 1980 frame" they do make these!classic industries has them.your iroc is the same as a transam in the 1982-92 era. they have a chevy powerplant and mounts. i have a 1984 trans-am that i'd be willing to switch from a chevy to a pontiac engine. the trick is besides fitment and clearance issues , is the fact they had trick mounts to mount the 326-455 pontiac motor from the mid 90's to around 2005. they may not make them any more.with this said it is a far greater task at hand to do the swap. we will see if i can locate any of the mounts or have one fabricated..patrick
the cost is related to the 455 rebuild ,which only you would know where your going there.if the exhaust system is in tact you could reuse it, the only other cost i see is the mounts for 326-455 (79T/A 400 motor mounts fit) pontiac engine and they sell for around $40-60.00..patrick
gary i also found out this about 1982-92 firebirds and camaros. you can use the following mounts on them to mount a 326-455 pontiac.: We do not know of a kit. Most people get frame mounts and engine mounts for a 76-79 Firebird and adapter them to the 1982 and later chassis.
okay cool thanks so much i was askin about putting the 455 in an 80's iroc or trans am cause i saw that alot of ppl were using them but i have a 91 transam with a 305 tpi. i was thinkin about puttin it in the 91 trans am but ppl were telling me it would be expensive because of emissions and i would have to burn a chip and all that fun stuff. so.. here are my options i wanted to do, option 1: rebuild the 455 and sell it, and then buy a 350 with a tpi set up not rebuilt and cam it, and put it in the 91 trans am i have. option2: rebuild the 455 and put it in an older iroc or trans am that i woul buy. or Option3: Put the 455 in the 91 trans am i have now. what would be the least expensive?
option 2 by far and wide.
----------
take the 455 rebuild it . a t/a get a BOP tranny if it doesnt have one, switch mounts. the z-28 you would need to change or fabricate every mount under the car. the t/a is cheapest
----------
the 91 would be fun........LOL
Last edited by woofy; 10-20-2008 at 08:58 PM.
Reason: Automerged Doublepost
ok cool ya im ordering the parts for the rebuild kit next week and i just wanted some input from other ppl. i also already have the trans. for the 455 its the turbo 400 i pulled it out of a 74 trans am, would that fit? I bought the car thinking it was the SD455 thats what it said on the hood, so i towed it home and i had the pontiac dealer check the num and it wasent the SD o well. The car was crap to! The owner before the guy i bought it off of used putty and aluminum foil on the body to patch the body! lol, who new it fooled me untill i started tearing it appart, anyway i got the guy to sell it to me for $500 and im parting it out on e-bay and so far ive got my money back and ive only sold like half of the parts. ill keep u updated on the rebuild and if i have any questions when i install ill post them up. thanks again
ok cool ya im ordering the parts for the rebuild kit next week and i just wanted some input from other ppl. i also already have the trans. for the 455 its the turbo 400 i pulled it out of a 74 trans am, would that fit? I bought the car thinking it was the SD455 thats what it said on the hood, so i towed it home and i had the pontiac dealer check the num and it wasent the SD o well. The car was crap to! The owner before the guy i bought it off of used putty and aluminum foil on the body to patch the body! lol, who new it fooled me untill i started tearing it appart, anyway i got the guy to sell it to me for $500 and im parting it out on e-bay and so far ive got my money back and ive only sold like half of the parts. ill keep u updated on the rebuild and if i have any questions when i install ill post them up. thanks again
when you get it be sure to post plenty of pics...and any parts yo wanna sell off that tpi let me know pm me and we can talk off the thread.....try to put it in and have the hood shut.....
Hey im been reading this post for a while and collecting parts and doing tons of research on this swap i work at a parts store so i found alot of my info through just grabbing some of the parts right off the self and check it out myself as for:
The manifolds i got ones off a 70 grand prix same locations im having a local exhaust shop make me a y-pipe
The mount is the only thing i really havent figured out exactly due to the fact i havent got it in there yet
The tranny im running a 2004-r out of a grand national for the overdrive. I have read tons of article saying that you cant get a 700r-4 for BOP, but you can if you want to keep that style in you can grab a 700r-4 out of a late 80's caddilac that had a 307 so you wont even have to worry about the torque arm mount or crossmember.
But thats all the info i can think of if i could help at all that would be cool. I know tons about pontiacs so ill try to help anybody
heres the scoop from the Holy grail of Pontiac. Mr. butler of jim butler performance adressed this issue for me. there are a set of mounts that belong to the 1976-79 era pontiacs' that will do the job just fine. the trick is to get your front to back and side to side location of the engine in the bay just right. and tack the mounts to the frame.When you set the engine in the car get your front to back and side to side location to clear the exhaust and it will make it easier. We have used the 1967 Ram air exhaust, 3 tube headers and custom shorty headers, You also can modify a set of headers made for another application. The wiring harness will just flip to the other side of the engine,the oil pressure sending unit wire will need to be spliced if you need it.There are trans crossmembers sold by aftermarket suppliers.Dale at, Competitive Edge, in IL. has done some of this,618-687-2392
The th400 going into that car is easy as pie b&m makes a kits along with tci makes one all it does is provide you with a either a new crossmember or a shim to move the mount location back thats easy enough then the torque arm issue is addressed by a bracket in the kit the mounts to the tailshaft housing and the torque arm mounts there.
And even go this root if your made of money and you like spohn stuff http://cgi.ebay.com/ebaymotors/Parts...=p4506.c0.m245
This is something you just specify what tranny your putting in and the crossmember will differ
its not that we need pics that much. we need exact info from some one that has done it:
What mounts? we all know if you can get the IA mounts that would be great but has anyone used the second gen ones
What headers/exhaust manifolds? we know that the ram air ones will do but their expensive and so are the IA swap headers which you need the tubular member for anyway. Im using the grand prix ones cause they look just like the ram air ones
point is we just need to have someone that has done it a billion times to give us advice which is not very likely
bottom line is this , what your doing isnt exactly cost effective. if your worried about money then i'd suggest a 383 stroker motor is the ticket. everything you are doing is fabrication when installing a 455 into a 3rd generation. yes second generation mounts work. more specifically 1976-79 mounts. when aligning clearance issues with the headers and side to side , front to back locations are met to exact tollerances and the location has been found to satisfy all of the above.you have 3 choices for exhaust manifolds,make your own, fabricate a existing set or use stock manifolds
i would suggest reading threads its helpful, butler performance addressed the issue for me and i posted the info on the thread.
----------
here it is again-->heres the scoop from the Holy grail of Pontiac. Mr. butler of jim butler performance adressed this issue for me. there are a set of mounts that belong to the 1976-79 era pontiacs' that will do the job just fine. the trick is to get your front to back and side to side location of the engine in the bay just right. and tack the mounts to the frame.When you set the engine in the car get your front to back and side to side location to clear the exhaust and it will make it easier. We have used the 1967 Ram air exhaust, 3 tube headers and custom shorty headers, You also can modify a set of headers made for another application. The wiring harness will just flip to the other side of the engine,the oil pressure sending unit wire will need to be spliced if you need it.There are trans crossmembers sold by aftermarket suppliers.Dale at, Competitive Edge, in IL. has done some of this,618-687-2392
Last edited by woofy; 11-07-2008 at 02:50 PM.
Reason: Automerged Doublepost
I just got a mild cam for it and the gasket and ring set so far. last sat i grinded smooth the ports and took the block out of the acid bath. im doing a semi stock rebuild. Not trying to get into to much trouble, if you know what i mean. im also still looking for what intake and carb to use. and of course the right car.
im thinking bout making a new thread with more pictures for when i get the car for this engine...
If you (or anyone, for that matter) put together a comprehensive thread on this topic, I'll sticky it and let this one fade into the sunset (perhaps it can be linked in the sticky).
Hey Guys, I was just reading up on this thread's progress. The motor mount issue was addressed in an early post. I'm pretty sure those custom swap motor mounts are still available.
Went to Chief Many Horses site & it is gone ?!?!? maybe they're not available now, Doh!
Last edited by Brother Al; 11-30-2008 at 05:33 PM.
Reason: spelling & note
Nice to see a thread to help those of us who want Pontiac power in a Pontiac. Now it may have been mentioned, but I kinda got lost at points due to the vast amounts of replies and such. Anyways, would the exhaust clearance issues and what not still be a problem even if you used a smaller Pontiac motor, like a 326 or a 400 instead of the 455? Just wondering as I see most talking about the 455, but don't recall any other motors mentioned too much. Also, would it be possible to just get a set of cheap shortie headers and have the exhaust shop make a y pipe or will those hit too? I remember reading about the ram air manifolds, but was hoping for a cheaper solution. Thanks for any help, and like I said, sorry if anything I asked about was already answered, but this is a long thread and I have read the whole thing.
Ok, what to do about the exhaust?
Most factory exhaust manifolds will fit, though slight trimming of the flanges or clearancing here and there might be necessary depending on which casting you are using. Its safe to say that all but the long branch style manifolds will clear the third gen chassis.
Indian Adventures makes headers for this swap, but there may be other, less expensive alternatives. I am still researching this, and plan to try several sets of off the shelf headers when my own project gets to that point. Several second gen headers work on BBC swaps into thirdgens with slight mods, and the Pontiac may be no different. I'll be building my own headers for this project though, since no one makes headers for a twin turbo setup .
any luck on headers????? what about block huggers? it would be better than manifolds i think parts american wharehouse has a set. im fixin to go through te sme thing.but really dont want to spend $600 in headers.
first 2 are Poncho block huggers, no tight tubes listed
__________________ 1977 T/A - sold
1985 Firebird - sold
1994 Camaro - sold
1978 Formula - 400 --> 463 beast winter buildup
1987 T/A - LB9 former dd project, make an offer
OK guys WAY back in this thread it was mentioned you COULD use stock 2nd gen mounts but what happens it it makes the motor sit high and it usually won't clear the stock hood. That said we also talked about how conversion mounts like these place the engine in the proper position and so long as your not using some crazy high rise intake manifold the car will retain the stock hood. I went back and found this link http://www.pontiacgroup.com/enginepa...part/10776.htm Pontiac Group sells them for around $90 for the set. That said if you look at these any decent welder with a drill and a metal cutter could make these pretty easy for probably under $30 in parts and a couple hours work. There was also someone on here who was making and selling them on here a year or two ago. I haven't done the swap yet but I got two 400 blocks sitting in my garage and a 91 F-Bird with a 305 thats giving death rattles.
Basically I came up with this. Get or make those conversion mounts $90, use stock 2nd gen log manifolds (free or next to it) or if you want better performance a set of ram air manifolds for which flow almost the same as headers anyway (but cost around $500) and get a muffler shop to extend the Y pipe to them (under $200). Want to keep your 700R4? No problem TCI makes a Chevy 700R4 to BOP conversion plate for $90 listed on summit.com. Pretty much figure out the fuel system and your good to go.
Me personally my plan is once the 305 breaks (or if I my greed for real power gets the best of me first). I am going to do what I just said above get the ram air exhaust manifolds, and have a Y-pipe made up. Switch out my ignition for a holley ahnihilator I got laying around and use a vacume advance HEI distributor instead of the computer controlled. Intake is simple aftermarket manifold, get a 454 truck TBI unit (which is basically what the larger holley aftermarket system is using) and modify a 2bbl to 4bbl adapter plate to mount it. Splice a few sensors and get a custom chip burned for the ECU. Other than that I was gonna leave it stock appearing with maybe a very subtle 400 badge under the firebird one if I can find one similar lettering.
__________________ -92 Firebird 5.0 TBI, 4L60
K&N Filter, Polyurethane Suspension update, Accel cap & rotor, wires, coil, and plugs. Dynomax exhaust, Alpine sound system, Adjustable Pan hard Bar, T/A Sway bars, Formula 17x8 Rims, 1973 350 Pontiac block .030, performer cam, 454 TBI unit and custom ECU tune (in progress)
~Show em the bird, light it up and watch em in the rear view...
OK guys WAY back in this thread it was mentioned you COULD use stock 2nd gen mounts but what happens it it makes the motor sit high and it usually won't clear the stock hood. That said we also talked about how conversion mounts like these place the engine in the proper position and so long as your not using some crazy high rise intake manifold the car will retain the stock hood. I went back and found this link http://www.pontiacgroup.com/enginepa...part/10776.htm Pontiac Group sells them for around $90 for the set. That said if you look at these any decent welder with a drill and a metal cutter could make these pretty easy for probably under $30 in parts and a couple hours work. There was also someone on here who was making and selling them on here a year or two ago. I haven't done the swap yet but I got two 400 blocks sitting in my garage and a 91 F-Bird with a 305 thats giving death rattles.
Basically I came up with this. Get or make those conversion mounts $90, use stock 2nd gen log manifolds (free or next to it) or if you want better performance a set of ram air manifolds for which flow almost the same as headers anyway (but cost around $500) and get a muffler shop to extend the Y pipe to them (under $200). Want to keep your 700R4? No problem TCI makes a Chevy 700R4 to BOP conversion plate for $90 listed on summit.com. Pretty much figure out the fuel system and your good to go.
Me personally my plan is once the 305 breaks (or if I my greed for real power gets the best of me first). I am going to do what I just said above get the ram air exhaust manifolds, and have a Y-pipe made up. Switch out my ignition for a holley ahnihilator I got laying around and use a vacume advance HEI distributor instead of the computer controlled. Intake is simple aftermarket manifold, get a 454 truck TBI unit (which is basically what the larger holley aftermarket system is using) and modify a 2bbl to 4bbl adapter plate to mount it. Splice a few sensors and get a custom chip burned for the ECU. Other than that I was gonna leave it stock appearing with maybe a very subtle 400 badge under the firebird one if I can find one similar lettering.
Thanks for "spelling it out"! A few of us needed a little more specific info.
Yes, this thread is very long and rambling, and information is hard to find within it.
If someone, who has completed a heritage Pontiac engine 3rd gen swap, who has thoroughly investigated available parts, and who understands Pontiac engine combinations, is willing to put together a write-up that summarizes all of this information, I will be glad to make it a sticky. This existing thread could be linked in that sticky if desired. The sticky really should be two parts - Part 1, how to get a heritage Pontiac mounted in a 3rd gen chassis; Part 2, engine combinations for best performance.
A good, summarizing write-up would be nice. Personally, I do not meet my own stated qualifications to do the job.
I can do this swap its just gonna take me time and with time comes great things. If u want i can seperate my thread when it gets to long so that you can make it two parts and sticky it that way. Im young and willing to do this for fellow thirdgeners and i promise ill cover as much as i can. Right now im in the rebuilding stage of my motor and as soon as i get the car i can experiment with diff. combos and parts etc.
Thanks, Gary
<--- Has the car, has the engine, knows what he needs..... Lacks the time and more importantly the money for parts to pull it off. I'm selling my 79 firebird formula project and if I get enough for it I'm gonna attempt this.
im also still looking for what intake and carb to use. and of course the right car. 
.
A few of us needed a little more specific info. 
