5 speed tremec
- Thread starter Turbotime
- Start date
This comes up every year.
There have been a few, and there are some strong emotions both ways on here. Digging up the old threads (assuming the search function is working at the moment) will provide some entertainment.
Personally, I'd love to drive a manual trans GN.
Bob
There have been a few, and there are some strong emotions both ways on here. Digging up the old threads (assuming the search function is working at the moment) will provide some entertainment.
Personally, I'd love to drive a manual trans GN.
Bob
It has been done twice that I know of. Once by a car mag and another is in a1st gen Nova. I can be done but you would be much wiser to use a Series II engine to do it. Much better block and heads than stock and you can get adapters so you can run just about any type of tranny you want in it, whether it's a BOPC pattern or even (God forgive) a ferd tranny.
novaderrik
Well-Known Member
- Joined
- May 12, 2004
It has been done twice that I know of. Once by a car mag and another is in a1st gen Nova. I can be done but you would be much wiser to use a Series II engine to do it. Much better block and heads than stock and you can get adapters so you can run just about any type of tranny you want in it, whether it's a BOPC pattern or even (God forgive) a ferd tranny.
the question was about a Tremac 5 speed trans.. so either a TKO 500 or TKO 600.. i think the general consensus is that a manual trans didn't work behind the TR engine 20 years ago, so it can't be done today..
it would make for one hell of a fun car if a guy could figure out how to maintain boost when shifting.. how do they do it in every other turbocharged car in the world that's available with a manual trans?
About three years ago we looked into using a Tremec 3550 or TKO for my uncle's Mustang. Many people that were using either one of these Tremecs in a Mustang were having problems shifting above 6500 RPM. We are talking about a new transmission here - this should not be an issue. Some were having the transmissions modified to shift easier at high RPM but a majority were not having good results. I think Libertys Gears was one company doing the modifications. You might ask if this issue has been resolved yet.
That's why I suggested the Series II engines. They should make a better torque curve for the conversion and it is a better block and heads to boot.
Here's some reading if you feel like taking the time to do it.
http://www.turbobuick.com/forums/transmission-talk/249065-manual-conversion-problem.html
http://www.turbobuick.com/forums/general-turbo-buick-tech/270868-5-speed-gn.html
http://www.turbobuick.com/forums/before-black-non-sfi-tech/272679-flywheel-clutch-get.html
http://www.turbobuick.com/forums/general-turbo-buick-tech/274863-t56-6-speed.html
http://www.turbobuick.com/forums/transmission-talk/282302-4-speed.html
http://www.turbobuick.com/forums/general-turbo-buick-tech/287129-3-8-stick.html
http://www.turbobuick.com/forums/transmission-talk/216543-here-official-manual-trans-thread.html
http://www.turbobuick.com/forums/transmission-talk/166589-manual-transmission.html
http://www.turbobuick.com/forums/parts-wanted/287128-6speed.html
RmvBfrFlght
Well-Known Member
- Joined
- Sep 28, 2007
They use a blow-off or re-circ valve to keep the compressor spinning while shifting.
RemoveBeforeFlight
I am still sitting on my flywheel and clutch pedals for this modification.
As it was pointed out using the Series II engine is a better idea as the thrust bearing isn't as big a potential issue as it is with the LC2. Not that Buick didn't ever mount a stick behind it's 3.8L V6.
Also BOVs don't work on Turbo Buicks, you can't fit a 315mm tire without a frame notch and they can't be auto-x/made to handle.
As it was pointed out using the Series II engine is a better idea as the thrust bearing isn't as big a potential issue as it is with the LC2. Not that Buick didn't ever mount a stick behind it's 3.8L V6.
Also BOVs don't work on Turbo Buicks, you can't fit a 315mm tire without a frame notch and they can't be auto-x/made to handle.
novaderrik
Well-Known Member
- Joined
- May 12, 2004
I am still sitting on my flywheel and clutch pedals for this modification.
As it was pointed out using the Series II engine is a better idea as the thrust bearing isn't as big a potential issue as it is with the LC2. Not that Buick didn't ever mount a stick behind it's 3.8L V6.
Also BOVs don't work on Turbo Buicks, you can't fit a 315mm tire without a frame notch and they can't be auto-x/made to handle.
and god help you if you think about using any kind of aftermarket parts that everyone else isn't already using..
DNA Strand
New Member
- Joined
- Jan 18, 2011
Simple, just don't let the throttle close. The throttle closes and the blow off valve bleeds off the boost so it doesn't shock the compressor. If you keep the pedal on the floor you won't loose boost.
Not that its really a problem to loose boost between gears. Think about it, you wind out 1st gear, shift at 6,000 RPM. Now you loose boost but when you shift into second you are around 5,500 RPM and you will build boost just about instantly at 5,500 RPM. Its not a real problem. In my mind anyway.
Good idea but that's not exactly how it works. If you route the BOV back in front of the throttle when the turbo "sneezes" it keeps the compressor wheel from trying to spin backwards. It really will do that when the engine RPM drops off, and if you use a light weight flywheel the RPM will really drop off fast.
Good idea but that's not exactly how it works. If you route the BOV back in front of the throttle when the turbo "sneezes" it keeps the compressor wheel from trying to spin backwards. It really will do that when the engine RPM drops off, and if you use a light weight flywheel the RPM will really drop off fast.
I don't think the turbo could ever spin 'backwards'. I'd love to see some data either way though. On a drop-throttle with no bypass valve, the flow definately goes backwards thru the compressor housing and out thru the air filter.
Anyone who has owned a manual trans turbo car knows that there really isn't a problem. I've owned 2 different turbo Stealths and driven the turbo Cobalt SS. Lots of fun.
Bob
manual trans seems to work well for this guy. (granny shifting....)
twin turbo firebird vs bike - YouTube
Bob
twin turbo firebird vs bike - YouTube
Bob
DNA Strand
New Member
- Joined
- Jan 18, 2011
Good idea but that's not exactly how it works. If you route the BOV back in front of the throttle when the turbo "sneezes" it keeps the compressor wheel from trying to spin backwards. It really will do that when the engine RPM drops off, and if you use a light weight flywheel the RPM will really drop off fast.
Well I know in the case of my WRX STi, the only way you will drop boost is if the BOV opens and vents the pressurized air. The BOV only opens when the throttle body is slammed shut under boost, if you flat floor shift it you will enter second gear under full boost. Now, like I said, it's not a good idea and you won't gain very much from doing this because even if you loose boost between gears you will built it back almost instantly.
I think a 5 or 6 speed GN would be a lot of fun.
