auto and turbo?

Is it even worth it to turbo or supercharge and automatic?

It can be but it cant be. You will get more of a turbo lag with an automatic than a 5 or 6 speed because the shifts are different. A supercharger might be more suitable for an automatic than a turbo.

don't turbocharge an automatic, the lag is SO bad, and by the time that it starts to spool up, the car shifts! if you do turbocharge though, you might want to get an ecu from another car with a more aggressive fuel map (gsr, etc..)

Would something like the PTS shiftronic help the lag problem?

are you guys talking from experience? obviously not.


autos are the best to turbocharge. unlike a manual, you dont lift your foot off the gas in an auto when it upshifts... by not having to get off the gas pedal, the turbo never spools down. once it spools up, usually by the second gear, it never spins down again.

on a manual, each shift you lift your foot off the throttle, thus closing the tb, blowing off the excess pressure thru the bov, then you shift, get on the gas, and then the turbo begins to spool up again. on an auto, all this is bypassed, and you get constant boost thru all gears until you lift off the throttle.

Originally posted by 90CRXZCSi
It can be but it cant be. You will get more of a turbo lag with an automatic than a 5 or 6 speed because the shifts are different. A supercharger might be more suitable for an automatic than a turbo.



actually, autos have less gears than most manuals... most autos are 4 speeds. due to this, each gear is longer, allowing the turbo to remain spooled up for longer periods of time.

Originally posted by gurlie
don't turbocharge an automatic, the lag is SO bad, and by the time that it starts to spool up, the car shifts!


it may shift, but it doesnt cause you to lag again since the throttlebody never closes, the turbo continues to spin at nearly full speed.

the lag is "arguable" in first gear... but by second, it's at full boost unless the turbo is entirely too large for the application. and once at full boost in an auto, it doesnt spool down until you lift off the throttle.

I had the same question but it's pretty much answered now..hey drift..do you think an auto tranny can handle a Turbo running at only 5-6psi? Im gettin a turbo for my car which is auto and im just going to keep it at the stock boost level cause im going to be running on stock internals..

the only thing i would say you would have to worry about is if the auto clutches are up to thr task of holding the power produced. and you might wanna look into getting a torque converter with a higher stall speed.

Jackson Racing suggested an automatic transmission cooler but did not say it was necessary, when I asked them about my auto holding up with a supercharger.

Another benefit of an auto turbo setup is you can come off the line with boost. You can hold the brake, hit the gas, and the resistance caused by the torque converter puts the engine under load, spooling the turbo right off the line.

I'm running a turbocharged 5-spd and I must say I DO get my turbo to spool off the line, but I have to hit 4-5k and when I let 'er rip, the front tires just skip off the ground and I feel like the dash is going to fall off. Oh, and that's on the stock tires, haven't tried it on my 18's yet.

you guys piss me of arguing all the time, just answer the question that the newbs (like me) ask

autos are good cars to turbo. but a trans cooler would be a good idea, it will help prolong the tranny life, or so they say. check out levelten they build auto trannys and can build you a bulletproof auto trans, but it will be expensive.

like the other were saying, you might not see full boost until second gear but after you hit full boost, youll be a full boost for the rest of the race

don't turbocharge an automatic, the lag is SO bad, and by the time that it starts to spool up, the car shifts! if you do turbocharge though, you might want to get an ecu from another car with a more aggressive fuel map (gsr, etc..)


You could not be so far from the truth :rolleyes: Turbos and automatics are like peas and carrots, they go together. Might want a higher stall converter. Besides you don't need to worry about spoolup with an automatic as much. You spool it up once and you are done with it. You don't loose boost everytime you shift. You accually gain boost (If you would not have a wasegate.) It puts the engine under more of a load and flows more exhaust at higher EGT's

I'm running a turbocharged 5-spd and I must say I DO get my turbo to spool off the line, but I have to hit 4-5k and when I let 'er rip, the front tires just skip off the ground and I feel like the dash is going to fall off. Oh, and that's on the stock tires, haven't tried it on my 18's yet.

:rofl: That's called wheel hop son, be prepared for even more of it when you put your way too big 18's with rubber band tires on, and probably some broken axles.

Autos and turbos work well when it is a good auto. Honda autos suck. They're weak, don't hold much power before they start to slip, and all around suck for power production. Besides, you can use a 2-step and leave with boost with a 5-speed anyways.

that's interesting about how turbo's click with automatic's better then standards. i always thought auto's suck, but when i read small threads like this, and i learn that they can put up just the same fight with things such as this.

Autos are better for drag racing, at least for us rear-wheeled guys... We usually use GM Powerglides or Ford C4 trans, you lose around 18hp through a powerglide and like 25-30hp through a c4.. The ammount of time you gain from a much better and much more consistent launch and quicker more controlled shifts easily offsets any HP losses. The big dollar top fuel dragsters run clutchless manuals, best of both worlds. But I can see how an auto would suck on a Honda, 30hp is a rather large % of your total power.. the difference between 570 and 600hp isnt really that much for me. I'd rather have the better launches.

30hp difference is alot when your racing someone with the same amount of hp as you. most serious racers at drag strips might have that much hp, but it wouldn't matter if your racing someone who doesn't have half as much hp as you.

Like I said, even if you are down 30hp because of the auto, you will launch and shift much better, and will most likely make up for any loss. Plus, if you're a serious drag racer, you can have a P-glide, ford c4/c6, and most any other v8 trans rollerized and lightened, which will drop those HP loss #s... those #s are for stock trans, you can probably get a c4 down to 15-20hp and a glide down to around 10-15.
Especially if you're running a turbo, you'll launch cleanly under full boost and not lose it through the entire race... That gain alone will put your far ahead of an equivalent manaul trans car.

so if the blow off valve lets out all the pressure after the tb closes wtf is it there wouldnt it be better to keep that all built up till you get the gas on again couldnt they make it so it only blows off when your turbotimer goes off when you shut the car off.

No.. with a manual, when the throttle snaps shut when you let off the gas during a shift, the pressurized air has no where to go, and the turbos arent making any more boost, so the air goes backwards thru the pipe and forces its way out through the turbo, which makes the turbo's compressor wheel 'stall', since air is trying to go backwards through it. So now you have a completely stopped turbo, that has to spool up from a standstill. With a BOV, it releases that air before it can force its way around the turbo, so the turbo can continue to sort of free spin, just keep spinning b/c of its inertia, so you'll spool faster with a BOV after a shift.

No.. with a manual, when the throttle snaps shut when you let off the gas during a shift, the pressurized air has no where to go, and the turbos arent making any more boost, so the air goes backwards thru the pipe and forces its way out through the turbo, which makes the turbo's compressor wheel 'stall', since air is trying to go backwards through it. So now you have a completely stopped turbo, that has to spool up from a standstill. With a BOV, it releases that air before it can force its way around the turbo, so the turbo can continue to sort of free spin, just keep spinning b/c of its inertia, so you'll spool faster with a BOV after a shift.

oh alright thanks

ermm.. good discussion... but did anyone check the dates on the thread? it's a 2002 :p