turbo six and stickshift questions

[elk93001]

I have heard that the turbo 6 and manual trannies don't mix that well for various reasons:

Some reasons that I heard:

transmission can't handle the torque

boost can't build up if using a 5 or 6 speed



and so on....


My question is, what are the reasons that this is not a good idea? Just curious.

(after all they only came with automatics every year they were offered.)

Thanks, in advance.

 

[Ttype83]

It's do to the turbo spooling up, every time you shift the turbo has to spool-up again.

As far as toque, I've run more toque on a big block...maybe the stage II's would have a problem with this. The Turbo Supra's have a 5 speed and I don't think they have a problem with this either.
HTH
Jim

Oh and good luck on finding a flywheel to fit that does not cost you a arm & leg

 

[gunnervirus]

Jim hit the nail on the head.

I finally found a used flywheel and clutch assembly from a guy in Washington!! 100 bones later, I had it, but it needed a new clutch and the flywheel resurfaced. I took it to my local Napa autoparts. They had to send the clutch out to a rebuilder, because they couldn't find a replacement. 250 bones later, it was finally ready to bolt in. $350 hard lesson for me... I will never do another engine swap as long as I live.

I now have everything bolted in and ready to go, except I need an exhaust system made, and my driveshaft and torque arm shortened. The hood hits the carb hat when I try to close the hood, but I'll take care of that last.

Something tells me I should have went SBC...

 

[elk93001]

With spooling a problem, could the wastegate simply be adjusted ? How about the EFE valve in the exhaust (adjust the vacuum to keep it closed a little longer)

Just kicking this around

 

[gunnervirus]

The wastegate only adjusts how much pressure the turbo makes, not how fast it spools. An automatic can spool up when the car is stopped because the torque convertor puts a load on the engine, a stick shift can't do that. That's the only drawback that I can think of. With a light car, your going to have good 60' times anyway. I'll have the car up in about a month or two, I'll let everyone know how it turns out. The EFE is just a restriction. I took the butterfly out and plugged the hole with some JB weld.

 

[Ttype83]

Originally posted by gunnervirus
I will never do another engine swap as long as I live.

Oh came on it's been fun..except for the fly wheel

I now have everything bolted in and ready to go, except I need an exhaust system made, and my driveshaft and torque arm shortened. The hood hits the carb hat when I try to close the hood, but I'll take care of that last.

Something tells me I should have went SBC...

When you are done playing with the manual trans swap to a auto.

I have helped with a couple of vega projects and some other swaps..... On the first vega, 350 sbc....we forgot to connect the frame. the first hard launch twisted the body/frame

Did you connect the frame???

 

[gunnervirus]

I think eventually I'll have to. I don't know how to weld, so I'm going to take it to a shop. I'm not too worried about twisting the frame while I'm breaking in the motor, because I'm not going to be pushing it very hard.

Ben

 

[Ttype83]

There still should be some bolt-in kits around for the V8 swap.
I know that they had them around about 20 years ago or so.

 

[gunnervirus]

The only ones that I've seen where the weld in type. I'll keep my eyes open for the bolt in kind. Those would be so much easier, because they can be installed in your driveway.

Ben

 

[pat83t]

Actually to cure the problem of having to build boost every time you simply put in a blow-off or pop-off valve. being that it is a draw-through system you vent it back into a carb spacer that has a pcv hose hook up and that will keep you from blowing fuel everywhere. As for buick v-6 turbos not responding well with a manual I call b.s. I realize that they turn alot higher rpm's than the street engines do but I don't know too many indy cars that run automatics and buick builds turbo-chargered v-6 engines for those, they just use pop-off valves. blow off and pop off valves are a good thing to have on the automatic cars also because it saves you turbo by letting the pressure go somewhere else rather than putting the impeller into the housing. as for running it on a drawthrough I haven't done it yet but that is the most logical way that I can think to run it and I am looking into other means yet.

 

[b4black]

I don't quite understand a blow-off valve. From what I understand, it's a relief valve that cracks (vents) at high PSI. If the engine hasn't built boost, due to lag, how can a BOV help? A BOV is like a wastegate for limiting boost right? I know it's sometimes used in a blow-thru to prevent compressor slam when the thottle body closes, but the turbo is still providing boost. In this case, a draw-thru woudln't need a BOV. It's see high vacuum when the throttle body closes. That's the reason for the positive displacement seal to keep the oil from getting sucked out of the CHRA.

Many people have tried a manual shift SFI/Turbo V6, but none with success that I know of. Their lag is small compared to a Draw-thru Carb/Turbo.

 

[pat83t]

Actually everything that I have heard about them is that they only blows off the excess pressure (adjustable) and then slowly bleeds off the set pressure when throttle is released allowing more time to shift and resume boost. This is what I have heard and I could completely be off in left field. What I need to do is contact HKS and ask them the exact benefits to having one of these and what would it do for a draw-thru system if vented back into the plenum before the compressor.

 

[b4black]

Originally posted by gunnervirus
The EFE is just a restriction. I took the butterfly out and plugged the hole with some JB weld.

I just removed the butterfly from a EFE valve. I'm not too keen on the JB weld for this. So I tapped the hole and screwed in a bolt with some Permatex Ultra Copper.

I'm keeping my fingers cross that the '79 manifold will work on my '83.

 

[Tonya83T]

Building boost

I don't understand what the big deal is about building boost during launch with a stick? My friends husband has a 300 ZX & he can build boost in neutral if he wants to. He uses some sort of pre-spooler. Without it he can't build any boost until he's moving though. He says he has other "importer" friends that have the same system on thier turbo cars. I don't see why we couldn't use something like this too? He said he bought his "system" complete ($$$$) but I believe the equivillent could be built fairly cheap. Turbo-Rich has been doing a lot of research on this subject. Especially after seeing Danny's 300 Z make 5lbs. of boost in neutral!

 

[gunnervirus]

Rich,

Is it a C02 system, or something? It sounds interesting. I thought about nitrous, but the car would have to be moving, and I'd have to spray on the launch. I don't know if my little tires (205s) would be able to handle that.

Ben

 

[Turbo-Rich]

His is a blow thru system. They are much easier IMO to spool up than a DT. What I've been delving into is Co2 injection of sorts but that's not what he's using. He has some kind of what I would describe as an air amplifier in front of his turbo's that's wired into his engines comp. somehow to supply exrta amount of air when needed to spool the turbo's. I think it was called something like e-turbo
He claimed that they were close to $2,000 a piece
I don't think they would do that much for a DT anyway.
I've been watching a budget oriented ($100-$200) pre-spooler system come together but it's too soon to make any claims on it's performance until more testing has been done. I personally believe this may be the hot ticket but I guess only time will tell.