jmedrano1991
Newbie
hey guys, im working on my 68 buick gs with no motor or tranny and im looking to stick a nailhead 401 or 364 in it and was wondering if it would even bolt up right. your thoughts would help TONS! thanks
1968 buick GS to a Nailhead! (help)
- Thread starter jmedrano1991
- Start date
Not sure exactly what you mean by "bolt up right". If you mean "bolt-in", it definitely won't be that. Basically, you will be building a 65-66 GS clone on a 68 platform, and you will need some fairly scarce parts to put this combination together. At the very least, you will need the 65-66 GS engine mount frame brackets and rubber mounts for sure, and possibly the GS exhaust manifolds also.
What kind of transmission do you want to run? If automatic, you will need a 64-66 nailhead TH400 or a 65-66 nailhead ST300. Anything else will require a rather expensive adaptor plate. For a manual, you will have to find a GS bellhousing. Big car bellhousings won't work unless you do some serious cobbling on the clutch linkage. No matter which transmission you pick, a 64-66 engine will make for an easier swap. However, a 57-63 engine can be made to work if you are willing to do some mods on the crank and flywheel/flexplate.
Besides the above, be prepared to put in a good bit of work on the exhaust, wiring, piping, and linkage. It would be a big help if you can find someone who has built a GS clone, even though yours will have some differences because of the car year.
Good luck on this, and please let us know what you decide to do.
Ray
What kind of transmission do you want to run? If automatic, you will need a 64-66 nailhead TH400 or a 65-66 nailhead ST300. Anything else will require a rather expensive adaptor plate. For a manual, you will have to find a GS bellhousing. Big car bellhousings won't work unless you do some serious cobbling on the clutch linkage. No matter which transmission you pick, a 64-66 engine will make for an easier swap. However, a 57-63 engine can be made to work if you are willing to do some mods on the crank and flywheel/flexplate.
Besides the above, be prepared to put in a good bit of work on the exhaust, wiring, piping, and linkage. It would be a big help if you can find someone who has built a GS clone, even though yours will have some differences because of the car year.
Good luck on this, and please let us know what you decide to do.
Ray
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I presume this question is in regards to engine/tranny mounts/location. No expert on this, but my guess would be that frame pads/mounts will be different. My understanding on the nailhead is that not much, if anything, is the same. I would contact Poston's Buick parts, or TA Performance... they should have a kit available as far as frame pads/mounts, or should be able to tell you if it would in fact, match up to the stock GS mounts (you fail to mention if yours is a 400 or 350). As far as mounting the engine properly, I offer this solution... Remove your stock 350/400 mounts (I highly doubt either will work with a nailhead), and with donor engine/tranny bolted together (with mounts in position on block and tranny), lower them into the car, installing the driveshaft exactly as if you were bolting the engine/tranny in permanently. Make the necessary adjustments in engine/tranny position to allow the driveshaft proper angle and endplay, and if the nailhead's frame pads and transmission mount fall into place where they can be mounted easily, mark off and drill holes as needed. If the stock nailhead mounts cannot find an easy mounting place on the frame, and there are no aftermarket solutions from TA or Poston's, then you will have to fabricate custom engine mounts.
jmedrano1991
Newbie
hey guys thanks so much, i really ap to preciate the help ALOT. it is a gs 350 (i totally forgot to mention). so were thinking 64-66 nailheads/ trannys are going to be the best bet?
Yes, if you plan to run an automatic. 63 & earlier came with Dynaflow, which isn't so good for performance. If you want a manual, the engine year doesn't matter as much. You would need to use a 65-66 GS bellhousing and whatever year flywheel matches the engine.
Ray
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Poston is toast. got sold to new owners and they ran it into the dirt at least two years ago.
Nailheads are cool but a Buick 455 or 231ci / 3.8L Turbo v6 would be much simpler to install. the v6 is the same engine family as the Buick 350 v8 and while the BBB 455 is not the same engine family it shares many design features with the SBBs.
Nailheads are cool but a Buick 455 or 231ci / 3.8L Turbo v6 would be much simpler to install. the v6 is the same engine family as the Buick 350 v8 and while the BBB 455 is not the same engine family it shares many design features with the SBBs.
BTW -- I have a friend who started building a Buick 455 that he lost interest in... almost ready to go together... needs dist/intake/carb/headers/timing cover... should be good for 350-375 horses... all prep work done, been in storage so may need some cleaning... He's asking $2500 for everything, spent over $5k