Turbo for SL

[VR43000GT]

Does anyone know where I coul find a used TT kit from a VR4 to put on my SL? And approx. how much would this run me for a decient used turbo set?

[crazy torino]

men you in the same boat. i'm tryin to put just one singal turbo on my stealth rt. but you cant try ebay, gredy makes a kit but it runs off the factory heardr. its not that pricy i think it runs from 1500-1800.

[Igovert500]

There is NO tt kit, a few members have 'kits' for sale that they have put together piece by piece from used vr4s, but basically apart from these people, you will have to track down everything part by part. Many simply buy a donor vr4 car for parts.
You could check out www.3si.org/forum for parts for sale, or otehr turbo ideas.

[VR43000GT]

Originally Posted by Igovert500

There is NO tt kit, a few members have 'kits' for sale that they have put together piece by piece from used vr4s, but basically apart from these people, you will have to track down everything part by part. Many simply buy a donor vr4 car for parts.
You could check out www.3si.org/forum for parts for sale, or otehr turbo ideas.

Can you gieve me the names or pyt me in touch with one of these members with these turbo systems for sale? Thanks

[Igovert500]

Hotshot had one he was selling a few weeks ago.

[Hotshot8792]

Originally Posted by Igovert500

Hotshot had one he was selling a few weeks ago.

actually, it's my friend who is trying to sell it, and he still has it. If you want to contact him, his e-mail address is [email protected]

[92VR4Red]

Ok I have to jump in on this convo... let me say this before I explain, it would be cheaper to buy a VR4 then to turbo a SL. Now let me explain. First and the most important, Compression. The compression on a VR4 is around 8.5:1, a SL is 10:1 if you just slap a turbo on you will blow things up so we are looking at some work on the heads, mabey rods, pistons,and crank. NOW once you have a engine that can take some boost you need to be able to feed it the proper amount of fuel :P, I'm thinking the SL did come with the same size injectors BUT the ecu doesn't know you have that turbo on there :P soooooooooo this means you will need some type of stand alone fuel system (stock MAS Air flow sensor is dif.), and a after market fuel pump. Now after you do some vacum routing and a boost controller and have the turbo working properly. you need a intercooler :P OH don't forget BOV. the air induction will need to be increased on the intake, the intake is much smaller ducts on a SL and the throttle body is too (need good air flow). Oh and I forgot you will need new exhuast manifolds and downpipe... Complet new intake system. and I bet I have missed some things :P

Now you have a front wheel drive VR4 that you spent probaly the ammount or more than what it would cost to just get a VR4. And not to mention the suspenison and drivetrain isnt probally stong enough to hold the HP on it.

I hope you see the expense of a turbo kit for a SL
(unless you want a baby turbo mabey pushing 7LBs or .5 KpS :P)

[Hotshot8792]

Ok, let me set some things straight here. The non-turbo motor can handle boost just fine. If your careful, you can generally run up to 10 PSI without any modifications to the engine, and 13-14 PSI with race gas, or alky injection, or even propane injection. Hell, i've hit 16.5 PSI on mine before on the stock SL motor.

Second, the N/A injectors are smaller than the TT injectors.

Next, you can get everything you need for the TT conversion for around $1500 if your careful.

My friend's asking price for his is $1100, but it lacks a couple of things such as fuel management and electronics, but has everything else needed to do it.

you can pick up a used s-afc for under $200, and boost gauge, EGT gauge, and datalogging equipment is however much you feel like spending.

Just had to clarify this information.

Though what is right, you will have massive wheel spin in low gears, but you will have mad top end pull.

And for the books, all manuals will need at minimum an LSD insert and upgraded clutch. An automatic will need at minimum a tranny cooler.

[92VR4Red]

I did say at the end that you can boost low with stock engine, did I not?... I'm saying it would be costly to "do it right" though I know its possible I personally think its a worthless effort on my opinion because I would rather have the all wheel drive.

[Hotshot8792]

Originally Posted by 92VR4Red

I did say at the end that you can boost low with stock engine, did I not?... I'm saying it would be costly to "do it right" though I know its possible I personally think its a worthless effort on my opinion because I would rather have the all wheel drive.

yea, well, on the drivetrain, to each his own

but as far as the low boost goes, you have to remember, 10 PSI on a 10:1 motor produces a lot more power than 10 PSI on an 8:1 motor

[92VR4Red]

Not always, but yet if so its terribly dangerous

[Hotshot8792]

Originally Posted by 92VR4Red

Not always, but yet if so its terribly dangerous

the same PSI level on a higher compression engine will ALWAYS produce more horspower than the same PSI level on a lower compression engine. The higher compression engine produces more energy and a higher overall compression ratio, which produces more horsepower. The final compression ratio on a 10:1 motor @ 10 PSI is approximately the same as an 8:1 motor @ 16 PSI. Now remember though, although these two have the same final compression ratios, the 8:1 motor will flow more air and still produce more power, but if you dropped it down to 13 PSI, the overall compression ratios are such a huge difference that the 10:1 motor will produce more power everytime. On top of that, if you are using stock turbos, the 10:1 motor will still prevail every time because the 9b's will hold back the 8:1 motor's performance. IMO, a 10:1 motor is perfect for a TT conversion for stock 9b's. Grant it, i have 8.5:1, and thats what i prefer, but 10:1 can work just fine as well. Your making it seem like its nearly impossible to TT an N/A car, and its not as bad as you think it is so as long as you go out and tune it at a low boost, then slowly work your way up.

[92VR4Red]

No argument with you BUT PSI is not what causes power... its the CFMs the turbos can flow through the motor.
CFM = Cubic Feet per Minute (air)
all tubros have a CFM rateing to so many pounds...
the stock turbos on a VR4 are not worth boosting over 18lbs... The max CFM rateing on the stock turbos is around 16lbs.
So PSI does controll how the engine will handle but the power comes from the CFMs.
more power can be produced out of the lower compression engine because its capable of flowing more CFMs. More air = more fuel = more explosion = more power. I had my engine built with 9:1 compression but is capable of boosting over 30lbs safely. the compression argument is legit its good to have high compression and boost, but the stock internals on a SL just wont hold over 10lbs with out haveing trouble somewhere down the line...
I'm just saying I like to play it safe and do things right the first time.

[Linebckr49]

Originally Posted by 92VR4Red

all tubros have a CFM rateing to so many pounds...
the stock turbos on a VR4 are not worth boosting over 18lbs... The max CFM rateing on the stock turbos is around 16lbs.

let me clear something up.

CFM is cubic feet per minute, as you said. this is a RATE of FLOW of the air in the intake. this is related to but different from the given pressure (lbs of boost) of the turbocharger. i'm sure the pressure is proportional to CFM for a given turbocharger: as boost pressure increases, CFM's increase.

i need to re-read some stuff on stealth316.com for the exact correlation between the two.

[Hotshot8792]

Originally Posted by 92VR4Red

No argument with you BUT PSI is not what causes power... its the CFMs the turbos can flow through the motor.
CFM = Cubic Feet per Minute (air)
all tubros have a CFM rateing to so many pounds...
the stock turbos on a VR4 are not worth boosting over 18lbs... The max CFM rateing on the stock turbos is around 16lbs.
So PSI does controll how the engine will handle but the power comes from the CFMs.
more power can be produced out of the lower compression engine because its capable of flowing more CFMs. More air = more fuel = more explosion = more power. I had my engine built with 9:1 compression but is capable of boosting over 30lbs safely. the compression argument is legit its good to have high compression and boost, but the stock internals on a SL just wont hold over 10lbs with out haveing trouble somewhere down the line...
I'm just saying I like to play it safe and do things right the first time.

Yes, i know that CFM provides you with more horsepower than PSI rating. This is very complicated to explain. First off, a higher compression motor will produce more horsepower than a lower compresion motor, assuming that there are know major differences in the heads and in the tuning. Next, compression, airflow, and fuel increase gives you an increase in horsepower. Now, specifically talking about the 3/S car, when you add boost to a 10:1 motor, the final compression ratio will, on average, be the same as an 8:1 motor boosting 6 PSI more. This, in theory, will allow the higher compression motor to make the same power as an 8:1 motor thats running its turbos @ 6 psi higher, assuming both cars have the same set up and same turbos. However, there is a draw back. The 8:1 pistons give just a little more room in the firing chambers to add an additional bit of air through the heads, allowing for some of that power to be made up, but does not flow enough to make up for the compression ratio differences. In other words, assuming everything is the same, its safe to say that two equal cars, except different compression ratios, once again specifically on a 3/S, a 10:1 motor will make approximately the same power as an 8:1 motor running around 4 PSI more.

Now, the advantage of the 8:1 is it leaves you more room for error, whereas the 10:1 motor doesn't, so boosting even more is more possible then of the lower compression. Hell, look at IPO, he managed to get 2/3rds the way down the track @ 28 PSI on a 10:1 motor before it finally blew, and there are some 600 HP DSM's that run a 10:1 motor on their turbo, they are just expert tuners. I'm saying that a 10:1 motor is not at all bad for running turbos if you know what you're doing, but an 8:1 will leave you more "breathing" room when tuning your car. Also, i forgot to mention that a 10:1 motor will also spool up the turbos much faster and will have a lot more low end torque than the 8:1 motor. Both motors have their advantages and disadvantages, it all depends on what you want out of your car.

Now, as far as the stock turbos go, going about the 14.5 PSI rating is just risky. They are soo inefficient at those levels, i dont care what intercooler you have, you are looking at a lot of heat, a.k.a the main cause of predetonation. Between their inability to run higher boosts, and the fact that they only hold around 10 PSI to redline, that is what just makes them soo much superior to run on a 10:1 motor than an 8:1 motor. Once you upgrade the turbos, then the 8:1 motor starts getting more superior, depending on what boost levels you decide to run.

Before i stop all this babbling, I want to clear one more thing up between different size turbos. Upgraded turbos obviously have the ability to produce more CFM. When comparing two different size turbos at the same PSI level, its really not so much the CFM levels that produce the extra hp @ the same PSI level. Assuming two different turbos on the exact same car, the cylinder heads and the
intercooler piping does not change in size. For this reason, there will only be a minor increase in CFM levels at the same PSI due to a slightly larger or bored out compressor housing. The reason for the extra dynoed horsepower is the turbo effeciency causing cooler air to come into the engine. Now, the bigger turbo will really begin to shine once you start increaseing the boost levels. Anyways, i think i'm rambled on enough about this topic for the night.