pianoprodigy

I was having a friendly discussion with another forum member who thinks that 400 rwhp on stock sequential twins is possible. I was under the impression that it is not. I've always heard that 360 whp @ 16 psi is about all you'll get. This person has a 365 whp dyno at 16 psi.

Anyways, is 400 rwhp possible on stock sequential twins on a stock motor? I know JD (Boostn7) made 402 rwhp according to his signature, but I'm fairly sure that was running nonsequential.

I know that even if it is possible, it's going to kill the turbos from all the heat. Regardless, ignore that. I just want to see a dyno chart (or hear reliable info) of a stock sequential twins car with stock motor making 400 rwhp.

Thanks.

Compilez

iTrader: (3)

If it is possible, the turbo's probably wouldn't make it 1,000 miles.

rotorsownyou7

Screw that, they wouldn't make it 100 miles.

pianoprodigy

.

rotorsownyou7

Possible, maybe, anyone done it, not that I know of.

Jay7 Nyc

iTrader: (3)

Look up screen name ' boostn7' he made 410RWHP on stock twins and ran 10s at the track..

rotorsownyou7

Dude, read what he wrote again.

Nuvolari

iTrader: (4)

400hp on stock twins, good luck perhaps one or two passes on the 1/4mile, you may have better luck looking for Bigfoot, or a Yeti

sk8world

iTrader: (5)

Hell, I was thinking 430 on stock ports with a single was good. On stock twins even running non sequential it a hell of an acomplishment..

njstreetrx7

nope actually the car ran good and was relible!!! but they didnt last as long bostn7 is one of the best at tuning the apexi

superior_force

assuming it's not bs, these are very good #s for 6500 rpm and Mustang dyno

https://www.rx7club.com/time-slips-dyno-121/spank-dyno-chart-411977/

Mahjik

iTrader: (1)

pianoprodigy,

Unless there are some old schoolers like Kevin or Jim who know something different, I've only seen a few "close" to 400rwhp with the sequential setup and those weren't on stock twins. One was artguy with the M2 twins (around 380rwhp) and kwikrx7 a little lower using the BNR's.

pianoprodigy

I was waiting for you to reply, and I had similar thoughts about hearing from Kevin or Jim. Hopefully one of them will find his way in here.

turbojeff

iTrader: (30)

Those aren't stock turbos, they do run sequentially. I drove it this weekend, it pulls pretty hard from down low!

Kevin T. Wyum

I don't recall anyone running at 400+ on stock twins in sequential trim. At anything nearing those power levels the sequential operation actually becomes a handicap restricting flow with no real benefit in spool time as there is essentially none. Why does it matter if it's running in sequential mode? Are you wondering if the stock wheels and housings can do 400+ or is this some silly pissing match you're having with someone saying, it didn't come from the factory in non-sequential!?

pianoprodigy

This person maintained that the 400 rwhp number was going to happen by changing nothing but increasing the boost and adding water injection but NOT leaning it out/tuning for the water injection. This post wasn't intended to spark a sequential v. non-sequential debate, but I was under the impression (correct?) that non-sequential twins will make more topend by sacrificing a bit of spool. I thought that someone may have made over 400 whp with non-sequential twins (JD, 402 rwhp according to his sig), so I wanted to clarify that I was only interested in the potential of the twins in the sequential setup.

tcb100

What difference would sequential versus non-sequential make for ultimate power? Once both turbos are on, they are on. How can there be a difference from from 4,500 RPM up?

matty

i tune on sunday with steve kan. Hopefully going to up the boost above my current 15psi. I have all the boltons stock twins and motor. so stay tuned. I doubt i get anything near that level but we will see.

If you do a search under my username you will see i have taken a pretty good amount of heat for this very discussion. I share your view but alot of the oldschoolers think 400rwhp and 120mph traps are attainable and more importantly safely done.

i will link a member who has one of the more vocal oppossing view to this thread

pianoprodigy

I didn't realize that this is the case. I was under the impression that there was some kind of "door" in the the exhaust manifold that directed air to either the primary or secondary turbo.

matty

going ns takes out some restrictions. more flow = more power.

Mahjik

iTrader: (1)

Theorectically.

For the most part, there is little difference on ultimate power; you just lose the low end. Rynberg posted two dynos of cars, one seq and one non-seq in another thread. The seq setup has almost 70 ft/lbs of more torque more than the non-seq in the lower rpms. That's quite a bit considering how little our torque numbers are as a whole.

However, many people have run into problems with the sequential system when trying to increase the power (beyond a certain point). This is why people going for power only either go non-seq or single turbo.

RotorFrank

I realized a little something while i was reading this post, can the stock injectors duty cycle handle the 16psi fuel map? If not what should i need? 850ccs all around?

matty

need to upgrade the inj. i have 1300cc inj. Pretty common to get these.

tcb100

RotorFrank, I run 17-18 lbs at the drag strip on race gas, with the stock injectors but an upgraded fuel pump. I don't think bigger injectors are needed with the usual bolt-ons. My duty cycles are 90%-95%. I don't know what other upgrades you have done to your car, of course.

Mahjik, the dynos I have seen eliminate the dip that occurs as the first turbo starts to run out of steam. You get a more linear plot, but I like low end too much to consider it.

Seems to me the bottom line is boost. If you get more boost non-sequential, I can understand more power but usually non-sequentials and sequentials pretty much boost the same when both turbos are at full bore. I run a cat so I have plenty of restriction anyway.

Boostn7's numbers are like Secretariat's heart - a freak of nature. The power he makes, his times, his 60foot times on drag radials, are simply unreachable by us mere mortals.

matty

thats a good et for having the cat in there.