this is as far as we were able to get right now. xs has the car running very very well and fixed some huge boost drop issues among other things. i was able to put down 381rwhp at approx 17lbs so far. Progress was made daily.

There are ongoing issues. I will explain below.

This winter i sent my twins to oz to have a larger secondary installed. My idea was to run them like the cosmo twins in that you have a smaller primary wheel(though still larger than stock) for quick spoolup and low end power...and then have a larger compressor wheel in the secondary to push the high end power numbers.

I did a lot of research and came up with no answers on why i should not go with this modification.

I finally put it on the dyno and have not as of yet gotten the numbers that I want. I consider this a full first pass due to issues with overly high intake temps and boosting questions left unanswered.

rotary reliability and racing did a phenominal job getting the car to this point...and xs really really worked hard to get it this far. It was a lot of work on both thier parts.

so here ya go...Im not yet done...Im shipping the car out here and am going to do some more work. I will be posting new sheets as I get them done. Once my intake temp problem is worked out I should do better with the dyno. Please god..dont make me go front mount.

Ive got some researching to do on my boost issue too that seems to be related to my decision to run two different compressors.




jason

PS..thanks to FD Racer (ray) for all the help along the way. And thanks to RRR and XS for the work done thus far. It wasnt easy...but it is progress. Thanks guys.

 

Congrats, looking good.

 

Hrm....it looks like the second larger turbo might be giving you a peakier torque curve. Do you think this would turn into driveability issues?

Blake

 

possibly...need more rubber at the very least.



j

 

Damn 319 lbs of Torque NICE. Good job. If you're having intake temp problems why not go V-Mount. Then you still have the sleeper effect but you've got great flow to the rad ic and intake. I think you're going to put down some great numbers with this. Good job and good luck.

- Steiner

 

Hey Jason, did you ever relocate the air tempature sensor from underneath the intake manifold? CJ

 

wow...and this is still seq?by the dip around 4500 im guessing so....anyway nice #'s

 

thanks...

pp13b...i have not moved the sensor.

something that xs handled extremely well is that i was having all sorts of boost drop issues and spoolup problems that i tried and tried to solve. they not only fixed that problem but my dyno chart shows how clean they got the sequential system working.


j

 

Nice numbers Jason. Its interesting to compare them to the BNRs. Seems like they're making a little more power than yours, but with anouther 3psi, you should be able to take em easy. CJ

 

Jasons are basically making the same power as the stock twins at 17 psi. (Rich made 368 rwhp at 15 psi) and Anthony made 386 rwhp @ 17 psi......The difference is the stock twins will last about 10 minutes at those levels. M2's are an improvement over stock.

Second, That BNR chart is uncorrected I believe. The car made ~402 RWHP corrected ?

 

I ran the stock twins at 18-19lbs for 3 years with no problems .....on pump gas no less.

John

 

i really dont think thats an accurate statement..i think it is a combination of propaganda and justification.

For the past four yrs i have yet to see proof...but whatever..what do i know.

 

well jodeny...yer one of a handful who pulled that off...i had two sets go in less than a year at 15lbs....heat made the wheels very brittle and they were going thru meltdown. that is one of the two main reasons that i went with the m2 set....the other was that i wanted to gain some low end back that i had lost when doing my streetport.

Matty: I had my own proof..i pulled apart my turbos and saw what running that level of boost was doing to the internals. before i upped the boost to 15lbs on the stockers my twins lasted approx 75k. I tried...i didnt have the same luck as jodeny. rotary reliability and racing does plenty of turbo jobs..they will tell you the same thing...the stockers are out of their efficiency range at high boost and they get very hot...leading to damage in most cases.

once the intake temps and boost issue is figured out it should make some more power...whether i have to go front mount or v mount or water injection or....

I expect to hit 400 at the same boost eventually...got some things to figure out first.


j

 

does anyone have the dyno sheets from a set of stockers making approx 380 sequentially? I wanted to compare the torque.

the torque down low makes me very happy at this point...which is EXACTLY what i wanted to regain after doing my streetport and losing it at that point in the power band.


j

 

i have chatted with u about this in the past and you make valid points. however, there are just as many people that have had problems vs those who do not...i can not draw a meaniful conclusion.

At this point i will run the stockers at 15psi..not constantly though..not b/c i am scared but b/c that level of boost is more then needed for street driving.

I am dyno'ing the stockers @ 15 psi with all the normal mods in a couple of weeks....i will post the results.

 

awesome matty...thanks...

i hope you have the same results as jodeny.


j

 

Very nice Jason. Over 200ft-lbs at 3k rpm, that is sweet.

 

Very nice Jason. Over 200ft-lbs at 3k rpm, that is sweet.

 

I'm going to be quite honest, I dont see very much difference between out numbers on the bottom end. Maybe 20hp here or there up to about 4K rpms but I havent even tuned at those lower levels and its VERY rich. I think with tuning I'd be making the same below 4K as you are.

My entire point of this isnt to trash the M2's but rather to say I think you'd make more power going non seq. I think going full non seq the only place you'd give up power MIGHT be the 2500 line but your going to make more every where else.

Dont forget eventhough I dont hit full boost till upper 3000rpms range (like 3800ish) I'm running 2 turbos....this means I dont need to make as much boost to make the same or more power.

This would also go for you, I think with those twins you'd have better power from 3K up if you went non seq.

STEPHEN

 

Hey now, who's to say I couldnt run another 3psi?

Jason, your numbers look pretty good so far, hopefully we can look at your tuning and get them up a little higher

STEPHEN

 

So what power were you making at 18-19psi with the stock twins on pump gas......and if you say you never got it on the dyno I'm going to say bs cause there is no way you ran that boost for 3 years without tuning it.

Well, I shouldnt say no way, but its very unlikely

STEPHEN

 

you have some great points stephen...and i see what you mean...at this point I will stay with sequential as it is the low end torque that I am after.

the whole point of me going with the bb set was to regain the lost power down low from my streetport...ive achieved those results thus far....my idea to increase the size of my secondary was done to try to widen the powerband as i said. the latter is not as successful thus far as i would have liked it to be.


Id love to see your sheets once you retune...I know you are happy with the car right now...who wouldnt be? if you can pull down seq numbers on a non seq set than I will be a convert for sure.



j

ps...just curious...on a your torque curve...do you think its possible to pull out 40+ foot lbs of torque at 3k and 30 ft lbs at 3500 just from tuning fuel? what are your afr's down low? is it possible to equal out a non seq and a seq car that way?

as soon as i get my car out here i will datalog it and send you the afrs, fuel, and timing maps to check out. Id really appreciate your input.

 

there is a point when one makes more power at lets say...17 lbs...than one would make at 18 or 19 due to the sweet spot on the efficiency range. bryan from bnr gave me a good discussion about that yesterday when i called to pick his brain about the boost issue im seeing up top that is causing the power to drop off after 7200rpms. you might find that you will make the most power at 17lbs...it will be interesting to see.


ps..jodeny..do you have sheets? I would love to compare them.


j

 

But its the hp number that is accelerating your car not the tq number.

As for me being about to jump up 20rwhp or so on the bottom end with tuning, I'd say its very possible. My a/f up to about 3500 is below 11:1 and the boost levels are so low it could be in the 13:1 area. That is a big difference. Not only will pulling that fuel create more power it will also get my turbos spooling faster so the tq is coming on faster...hense the hp is coming on faster and higher. See how my hp line slouches in the lower rpms, it should curve up slightly. Thats all from the lack of tuning down there.

You see my line from 5K-6K, if you draw a straight line straight from there down to my starting poing that should give you an idea of what the potential is with a lot of tuning to get it perfect.

STEPHEN



STEPHEN

 

what't your boost pattern on seq?