I have tried setups of gt35r and while it is making good power, i think the spool is a little slow for what i need. I will be building a car for drift, i know the RX6 is probably the best turbo kit i could get for low rpm power but i hate the fact that you need to buy a new turbo at 2000$ every time you blow an apex seal. Is there a turbo that would be similar but would be rebuildable, something smaller than a gt35r?

Also, would it be better to keep the stock port on the engine or would a streetport help? I like to go at 2000rpm in second and want some sort of reaction from then engine when i suddendly push the pedal. Maybe i should go LS1...

 

http://cheapturbo.stores.yahoo.net/garrettgt3071r.html

^ with a T3 .63 A/R


the bigger the port.. the less the low end power.

 

To4e 57trim .70 a/r O wheel

 

Sure that will come on fast, but there will be a serious lack of torque. Backpressure is the enemy of torque. Just look at stock twin fds, sure they hit 10psi right around 2000rpms but they aren't going anywhere. Same with greddy turbo8s, or stock turbo 2nd gens.

As far as the porting goes, if done correctly it will help spool the turbo faster, but most the time its done where all it does is hurt the boost threshold and overall power..

50 trim To4E with a P trim wheel, and a completely well built fine tuned system, otherwise get a v8...

 

It doesn't matter what turbo or supercharger you put on a 2 rotor it isn't going to make decent power under 3,000rpm.

The very best you could hope for is ~130RWHP at 3,000RPM if you use stock FD sequential twins, some tiny BB single or a supercharger so you have FULL boost at 3,000rpm.

But then, even drifting poorly I don't see how it would be difficult to keep the engine between 4,000rpm and 8,000rpm where you will have 200RWHP and above.

Get a decently small BB single and then concentrate on all the mods that lower the boost threshold and you should have boost off idle and full boost around 3,000RPM. I have that with a 60-1 stock hybrid...

 

If you really need grunt, would swapping to a 4.77 (or something like that) final drive be a better way to spend your money?

 

I'm trying to word this the best I can without coming off like I'm trying to bash you but how are you putting your self in a situation where you need boost at 2k to drift? Most of the time you start your drift at 4-6k rpms and if you find your self a little lower than that you either downshift or clutch kick to get the rpms up. It almost sounds like your setting up for autocross where good low end power is needed inbetween turns and on the short straights. Maybe a change in techinque would solve your problem?

 

lol, to be honest, this is not for me. What i meant (you are right, that was poorly explained) is that i want boost as soon as possible. I beleive threshold is the right word as lag is more about the time it takes to get full boost from when the boost start (maybe i am wrong, please correct me if my word choice is bad). What i am interested in is how soon the boost starts rising. On stock twins, you can get 10 PSI by 2800, i really, really like how the low end power comes on with the twins. I dislike though the transition from first to second turbo and the fact that you are limited in such low top end horsepower.

I have a friend who got a turbo kit built by someone who had no idea what he was doing for an rx-7 and he installed what was suppose to be a GT35r but looks smaller than that. Most of all, the exhaust housing is way small. I thought this car would not make more hp than the stocker but this happened to be the most fun car i ever rode. His exhaust housing looks something like a .56 or .68.

It is far from making as much hp as the other "regular" GT35r i have tried but damn that thing spools fast. It probably makes something like 380whp at 15 PSI.

in 2nd gear, he gets his 15 PSI by 3200-3400 rpm, which is pretty incredible

This is the kind of kit i am looking for. Problem is, we have no clue about the specs of his turbo.

This is for an FD by the way. I'd also like a turbo that doesn't have an internal wastegate.

thanks for your feedbacks guys, very appreciated.

 

even if you ocpy the turbo setup to a tee, it might not be exactly the same , as all setups vary a little from tuning, IC setup etc etc.

But If you really like that setup I would see if its possibel to measure the compressor wheel ( take compressor housing off )and the turbine wheel . And you can visually see the AR on the turbinehousing so jut plain simple copy the setup.

but that being said.

I think the to4e in 50 trim with a .84 p trim with a nice 50mm wastegate will perform perfectly for what you want.

( heck if you want even smaller for with a .70 AR turbine housing ) that will definilty spool ridicoulsly fast.

 

I agree. I drifted in a v8 s13, and then a ka-t, and it was much easier to drift the v8. The broad power range, and the instant power were just crazy. I almost re-logged into that v8 rx7 site, but was able to hold off. The low end power just isn't going to happen with our type of engines. Even making a setup dedicated to it, will only raise it 10-20 torque down low. I have came to the conclusion, as will you, that our engines are NOT the best for easy drifting. Finding the right turbo, and keeping the power as broad as possible, will help limit the 13b's peakiness. But don't get depressed, as stated above, driver skill, and learning different techniques can make help you overcome the engines shortcomings.

I do drift my s4, and I consider myself to do better then average. I just don't see, how I could ever start and hold a drift under 4k, even at full boost. (unless I was to clutch drift and rev to 5 or 6k.) But then again, I drift with good rear tires.

I hope this helps, if not, I'm sorry for the babel.

 

FWIW, I get ~130 whp @ 3krpm, non-sequential twins. Boost is about 6 psi at that point in the rev range. See attached chart. See THIS POST for more information about the car.

 

el es juannnnnnnnnnn

j/k i liked my gr63 alot.

 

Selling my 4.44 ring and pinion right now https://www.rx7club.com/showthread.php?t=714046

 

I am not seeing it in the dyno charts in either post. Are you thinking of the torque at 3,000rpm?

It looks to me like you have about 75RWHP at 3,000rpm as is normal on a non sequential set up or big 500-700RWHP single turbo.

Looking at dyno charts you will see a good efficient 400-500RWHP single turbo set up will hit 100RWHP at 3,000rpm.

A well modded 300-350RWHP stock sequential twin or small single turbo set up will hit 120-130RWHP at 3,000rpm.

A good non turbo set up will hit 60-65RWHP at 3,000rpm.

As far as torque goes, a faster spooling turbo will show much much more difference in low rpm torque than low rpm hp.

For instance a stock S4 TII makes 20% more torque at 1,500rpm than the NA has PEAK torque and I am sure the 13BREW (and more so the 13BRE) make even better low rpm torque.

 

I was misreading my own graph. My fault. Thank you, you are correct in that the torque is 130 ft-lb, with a corresponding 74 hp @ 3,000 rpm.

 

So you want torque huh? Sequential BNR stage III's with a 4.77 final drive!!!
Oh and you'll prob need some reeeal sticky tires
-J