I still havn't been able to sell my S15 T28 turbo off my old SR20DET. i just bought the thing and only put 1,000 miles on it but i was wondering since i already have one buy another and fab. some pipes that fit everything.
Just wondering if some else on this forum has tried to put indepent twins on an FD? Work well or did it have its problems? One of the problems that i already see is space. next is the exg. manifold, there is no way the thing will be equal lenth in order to make the turbo fit. and DP space which will start with two 3" pipes that will have to collect befor the down drop accours b/c of space resterictions. Just want to know if this would be worth doing or if i should keep dreaming.
Rob

 

Wonder what the power band on that kind of setup would be?

 

well on my SR it spoolled really early 2900-3000 and hit full strong 12psi at 3700 untell redline. but by it's self you can only muster 15psi of strong boost on a SR20. most of the other cars i drove would be set to spike to 18psi then drop down to 15psi till redline(lack of airflow). God i loved the ablity to just beat the $hit out of the SR20 and have noproblems with it. i would never try to pull that with the 13B. but i would say they could handle at least 20psi together. mine also has the upgraded dual ball bearings so spool time for both should be minamum for the engine tring to push two decent sized turbos

 

RX7Store used to offer a $5000+ GT28 twin turbo kit, fully non-sequential. Power was in the 500+ (prob 600 or so) range. Do a search for it.

 

i did the search and i found them. hopefully they are not too much(no price) i was trying to save money by building my own kit since i already have one of the turbos. if its more then a single then i sell the T28 and buy a single kit. if i don't use it anybody interested in buying a GT28

 

For the cost and time to fabricate your own quality twin setup you could buy 2 or 3 complete single turbo kits. Equal length is not a problem either. From the sounds of it though fabricating a twin kit would be way over your head.

 

I have the twin gt28r setup and it is actually 400-450 rwhp with a ported motor. Quick spool though. Spools slightly faster than a gt35 with power close to a gt42

 

Wow. I couldn't find it on RX7Store's website right now, but I coulda sworn it said 500+ hp. Guess that was at the crank... That's a lotta $$ for something the new Stage III BNRs can do.

 

I paid $3200 for them and trust me, they were worth it. I think that rx7 store decided not to deal with them because they are a serious pain to install and the wastegates are a bitch to syncronize. But once everything is set and tuned........sweet.

 

this is something i have wanted to do... or thought about but in the UK it is 4 x more expensive then a single turbo conversion .
Makes better sense to have twins as less lagg .

 

i think the miata peeps use that size turbo.

 

having the two GT28s, would the turbos be set up be where the stock turbos are?..or is it gon be a lil bit more up-front with one above another instead of one benind the other?

 

According to Jason at the RX7store,

"We tested a twin GT28RS kit and found that its not worth the extra cost. They didnt out perform a single turbo and didnt spool any quicker. Larger turbos are going to be real laggy. They did look good and a unique setup.

Jason"

This is from the thread https://www.rx7club.com/showthread.p...2&page=1&pp=15

I however, am still interested in learning more about your results with the twin GT28R turbos (as I am still trying to determine if I'll pursue such an option) - would you happen to have any dyno sheets to illuminate us on the performance of the parallel twins?

Additionally, what type of porting does your motor have, and are you running a fully open exhaust?

Thanks!

 

Do a search for user name "broken93"