# Swapping a 66 from the standard 335 to the Tripower?



## xconcepts (Jan 4, 2009)

So the 66 I picked up I also got a Tripower engine with it, FOR FREEarty:. Now my delima is should I swap the engines? The trannys not original already since it was swapped from a 3 speed to 4 speed. So instead of rebuilding the standard 335 I was thinking I could rebuild and upgrade a few parts with the Tripower and swapping. Opinions?


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## geeteeohguy (Feb 2, 2008)

Rebuild the tripower engine and store the original one for safekeeping. Check out Ross Pistons or other sources for dished pistons so you can run the stock heads with pump gas and not destroy the engine. 389's do NOT like 92 octane fuel with their stock 10.75 compression. You need to run about 9--9.5 to 1. Have a reputable machine shop do the work, one that does more than just Chevys, and go basically stock. It will be dependable and fast. Good luck! I wish the Tripower Engine Fairy would visit MY area....I could sure use a free, spare tripower engine!!!!


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## Rukee (Feb 8, 2007)

:agree
Drop in the whole Trii-Power engine! :cheers


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## Too Many Projects (Nov 15, 2008)

xconcepts said:


> So the 66 I picked up I also got a Tripower engine with it, FOR FREEarty:. Now my delima is should I swap the engines? The trannys not original already since it was swapped from a 3 speed to 4 speed. So instead of rebuilding the standard 335 I was thinking I could rebuild and upgrade a few parts with the Tripower and swapping. Opinions?


DON'T DO IT..........it's gonna be waaaaaaaay too much time, work and money. Shoot me your address and I'll come get it out of your way ASAP.........

















Some people have all the luck, eh Jeff ??? 
A FREE tripower........sheeeesh.


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## geeteeohguy (Feb 2, 2008)

A guy gave me a FREE '66 GT0, 4-speed/console/guages/posi car. Had a 2bbl 350 in it, though. Had been wrecked in the front, but not bad. I drove it home. Good running car....I put a front clip on it and sold it for $700....the guy never paid me the final $400 he owed, so I sold it for 300!!! He drove it for years until he got it impounded.....I went to the yard with my lein in hand, but the impound fee was $2700!!! This was about 1985.......I could sell the CENTER CONSOLE out of that car for what the whole thing went for, now!!! But no, nobody ever gave me a free TRIPOWER!!


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## VettenGoat (Jun 19, 2007)

Seriously,it that a joke? Anyone who has searched for a period tri-power motor knows they are as rare as chickens teeth. Just out of curiousity, is the casting date on the block within a couple months of your cars build date? Either way if you have a complete 66 360 hp/tri-power motor I'd drop it in, if its date correct I'd absolutely drop it in. The pre-existing turbo 400 clinches it.

I draw the line at putting tri-powers on 335 hp blocks, but a matching tri-power motor...not a second thought. Just save your old original block. 

Mike


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## xconcepts (Jan 4, 2009)

Wait I'm lost, I thought the Tripower was a 389. So the tripower block could be a std 335 or a 360/389? How would I know if its the pre-existing turbo 400? I'll have to ask about the casting date, since I'm still in Iraq.


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## Rukee (Feb 8, 2007)

You could put a Tri-Power on a 335HP block, only the cam and intake were different.
A turbo 400 will have a single wire kick-down connection on the drivers side just about the pan gasket with no mechanical kick-down cable going to the carb.


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## geeteeohguy (Feb 2, 2008)

389 engines in GTO's NEVER came with a turboydramatic 400. Only the full size cars did, in '65 and '66. All GTO 389 automatics were 2 speed, heavy duty superturbine 300 (powerglide) units. The GTO didn't get a turbo 400 until 1967, when it also got the 400 inch engine!


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## VettenGoat (Jun 19, 2007)

XConcepts, welcome to the neighborhood, I doing time in Baghdad now myself. All the blocks used in 66 GTOs were 389s. The tri-power was the 360hp option version of the 389 and had a WS code (My reference materials are at home and I forget what the automatic code was, Y something for a 360hp automatic trans. GTOGuy is right, only 2 speed slush box automatics were available in 66. Check your engine codes and casting dates when ya get home (it give a little something elsi to look forward to doing). I'd leave the respective motors intact (i.e. rebuild it, but don't swap component between the 335 and 360 motors). Personally I'd drop in the 360 hp tri-power motor as a complete unit, but if you just want to cannibalize the intake, I'm sure there's a 66 owner out there thats been looking for a correct 360 hp motor for a long time and a sale would be pretty easy. Points off for a 335hp with a tri-power though.
Be safe
Mike


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## xconcepts (Jan 4, 2009)

I wasn't looking at cannibalizing the 2 engines, just rebuild the tripower with a few parts or whatever to get it to last and run well, drop it in and save the 335. I'm sitting in Balad right now, got another 2 months here.


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## VettenGoat (Jun 19, 2007)

Absolutely right. I gotta tell ya the tri-power is fun. It seems like theres more tri-power Goats today then back in 64-66; every period GTO seems to suddenly be a tri-power. Hence my recommendation to use the entire engine. Sounds like you get a really sweet deal, so savor it. I was up in Ballad back in late Feb-Mar timeframe when they were dropping 20-25 rounds a night. So many T walls up there it was all compartmentalized anyhow and I don't the insurgents didd too much damage. Baghdad's been really quiet the last couple months with only an occassional car bomb. Hope they were Fords!!
Anyhow I'm stateside mid Feb too. Be safe//Mike


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