Upgrading Twins...
 

I was thinking of doing a single turbo conversion on my VR 94, but I allways liked the idea of having twins so I am just going to up grade those. RX7 Store has a good deal on a twin t-28 package. so here is my question...

I know all the parts needed to go single. What parts would I need to do a succesful upgrade to the twin t-28 turbos?

Aren't t-28 turbos known for being as laggy as a single turbo, you can only run them in parallel anyways, if you want to upgrade your twins the right way do the BNR upgrades on rx7store.net

They have great deals on stage 1, 2 and 3, good, from what I hear for about 470whp. Up to you tho, if theres a way to run the t-28's sequentially, it MIGHT be worth it, lets wait until the gurus answer, just trying to do my part.

Wow. That is a pretty wild kit. If you are street driving and some track duty, I'd say go with some nice upgraded BNRs also.

there are alot of different twin turbo set ups, i think with the t28's though, unless they are sold in a rx7 specific kit, will need some custom high-mount set-up,
same kinda deal with the single, but more piping.

rest of the kit you will need is the same as going big single, ie, ecu, most probably injectors, radiator intercooler ect.

yeah i would go witht he BNRs too! :)

I fourth or fifth the BNRs, man - that twin kit is still pretty new...not sure if anyone has tested it long enough to be 100% confident in it, you know? You never want to be the first one to do something like that unless you have tons of money to fix any mistakes that happen

"They have great deals on stage 1, 2 and 3, good, from what I hear for about 470whp"


do you mean 370??

ive heard about bnrs having lots of trouble. smoking, etc. anyone confirm this?

The first batch did but that was corrected and all those were repaired under warrenty.

Actually he's not selling stage 3's right now just stage 2's. He is currently working on a new setup for stage 3's cause it was hard to find parts for the other design. I'll be testing out the new stage 3's pretty soon and I'll report back with the info. It'll prob be 6 weeks or so.

STEPHEN

No I think he meant 470 :D

the m2 ball bearing units should not be discounted. I have had extremely good luck and strong numbers with them.


kan is finishing my tuning xs started and we are upping my boost a week from saturday. I will be doing new dyno pulls. Hopefully I will see an improvement in hp and tq at all levels.


j


i cant wait to see the results of those new bnrs though stephen. its going to be fun to see how they do.

:rlaugh: :rlaugh: :rlaugh: :rlaugh: :rlaugh:

The BNR twins are good, but they're not near that good.

See Im kinda a rx-7 purist. want to keep my car along the original guidelines. Rotary, Twin Turbo. Is the a good twin setup out there what will give me the specs and power im looking for? (Besides BNR or M3).

What other kits are out there?

I understand they will be as laggy as a big single. But there are some single onwers who would say the lag is not really that bad.

The Paralell Setup I dont mind. And the High Mount custom job Wold not be that hard. I have seen one person With a similar setup. It was on www.Cardomain.com . It was a red FD with Black (power coated) Rims.

Maybe you could find a way to hook up a T03/04 then have it switch over to a T-78. I think that would be pretty sweet....wouldn't last long though.

I can't imagine why you would use twin turbos to produce the same results as a single.

The reason that the factory used twins was to achieve the quick-spooling responsive performance that the SEQUENTIAL system delivers.

If you wanna run the factory twins in parralel, thats your choice, at least the mod is cheap...

but why the you'd pay MORE $$ than a single kit for two turbos to then NOT use them in a way that would be beneficial to you (sequentially) is beyond me. All you've done is paid for unecessary complexity....

Strange. I read in their post that that BRIAN himself from BNR Racing and Stephen were making those numbers.

https://www.rx7club.com/showthread.p...t&pagenumber=1

Ive never actually installed the turbos, but if the stock turbos have what it takes to make it to 350rwhp or MORE when properly tuned, why wouldn't thesemake it to 450+?

the bnrs are good up til 17psi. you will get more power out of them at 17 then 18. it is all about efficiency ranges. i think the most anyone has made on the 3's is stephen spoautos at 404rwhp

the most anyone has made on the stage 2's is 370rwhp.

the most anyone has made on the m2 set is 381rwhp. I am not done tuning though and will be finishing it up and providing new dyno sheets a week from saturday. steve kan seemed confident that he could get more power out of my car in all areas on my sheets.

Im adding the new aem ignition to help clean up the break up...up top on my sheets. Im reaching for the 400rwhp area. Im hoping we can reach past the 404rwhp mark set by stephen on his bnrs...we shall see if i can do it with a sequential setup. Im excited and kan sounded optimistic about what he could do with my car.

the new stage 3's should spool a little slower due to the thicker shafts. Im looking forward to seeing the dyno sheets on them just for comparisons sake.



jason

Hey Jason.

Stephen dynoed 412 RWHP with low 11 AF numbers and very conservative timing and split. That number was also made with 93 octane. Air intake temps were around 35 celcious.

In street conditions at a lower intake temp, you will definately see more power at the ground, but it isn't proven on a dyno so I guess it doesn't count! lol.

Garfinkle has the new stage 3 set , ( bigger wheels,shaft , intake houseing ) ,with custom install . It runs good but is not tuned as of this date .The tuning may be done the first week end of March .

awesome....thats what Im shooting for too. where did i read the 412 was uncorrected and that it was actually 404? maybe i am just getting alzheimers. either way they are the numbers to beat.

will your new upgrades beat those numbers? did you get them on your own car yet?


naah..i know that the dynos are off from actual street numbers...

such a long wait for the goodness....i remember being there....garfinkle ya must be jonezing for the tuning...i sure was.

best of luck...cant wait to see how ya do.


j

what about the m2's spooling ability?
Ive heard that the m2's spool up faster than the stock twins.Also how do they compare to the bnr's spooling ability?