I finally got my fd tuned on Wedensday. It came in at 298rwhp @ 6300 rpm with a little under 12psi on a mustang dyno. I went to Forged Performance in Portland, and Brian, the tuner, said he didn't like to push much over 300 on just pump gas. I know its not that much, but I'm just happy that it's finally running right. Now I guess I'll save up for a A/I kit so I turn up the boost

Here's a short mod list:

Pettit street port motor
BNR stage 3 sequential
850/1300 injectors
dual walbro pumps (suggested by shop because I'm shooting for 400hp by the end and my Supra pump burned out)
HKS Twin Power
HKS intake
Apex'i fmic
Power FC
Lots of others

 

I'd recommend going somewhere else (read: rotary specific) for a better tune, there's no reason why you shouldnt make 375ish+ rwhp on pump gas with your setup.

 

^^This

 

why cant you do over 300 hp with pump gas? I would love to know the reason from him, especially since a lot of higher hp cars run off pump gas still. For example the lingerfelter vette with 900+hp runs off of 93 octane which is only 2 points higher than cali standards but is still a decent example IMO.

 

I made about 335whp on similar mods (I had a SMIC, not FMIC) at the same boost with stock ports.

I'd def suggest finding another tuner, what was your AFR?


And I believe 15psi is the "magic number" where you may want to consider running more then just pump gas for pre-det safety... that should be closer to the high end of 370-390whp for you.

 

what was your injdutys? my cars almost the same, except i have a stock mount. and i have a supra pump

 

i make the same power on stock turbos :|

 

The BNRs make similar power as the stock twins below 14-15psi. The BNRs really start to shine once you get to, and above, 1 bar.

 

It sounds like your tuner doesn't know his way around a rotary. We tune to over 400whp every week on pump gas. You do not need AI to get more power, you just need a better tuner. All of our tuning is done on a mustang dyno as well. To put things in perspective, I recently tuned a stock FD (still has the smog equipment), just a DP, RB catback and PFC to 294rwhp @ 12.5 psi. http://www.banzai-racing.com/dyno_ch...o_05-18-09.jpg

Our 13b-re vert is 435rwhp @ 15.4psi on pump with no AI. http://www.banzai-racing.com/dyno_ch...o_06-23-09.jpg

 

My AFR's were in the mid to high 10's. I don't know the injector duty cycle. I didn't ask him, and I'm still trying to learn how do all these things with the datalogit.

I found out about Forged Performance from this forum and have heard great things about them from Rotary Performance and Pineapple Racing, which is in the same complex as Forged. Rob at Pineapple said that he sends everyone in town to them. The guys who own Forged used to work at Ground Zero too. They work on lots of RX-7s there, especially fd's. When I was there, there were about seven or eight other fd's there getting work done.

I'd heard about the 15 psi rule, and that's what I went there planning on. The reason I was given for not pushing for more power was that we don't have the greatest gas here. We have 92 octane with 10% ethanol. He said that with about 300 hp, I should be able to handle getting a bad tank of gas. Going with A/I for more than that is just for the added safety factor.

So, since everyone's saying to find a better tuner, does anyone know someone better in Oregon? I'd love to be able to make more power and get a better tune, I just haven't heard of anywhere else in this area.

 

You can blow your motor on a bad tank of gas at 300 rwhp...... go fill up with 87 octane and start making redline shifts, see what happens

 

I have commented on this before in my thread about DIY Power FC Commander tuning https://www.rx7club.com/showthread.p...62#post9361762. Generic "tuner shops" are often of limited value. If I were that tuner, I would've either 1) not accepted your business (probably what he should have done) or 2) pulled the plug early like he did so he's not just another guy who blew up a rotary

Did he even hook up a Datalogit? I would be concerned about the trailing timing from somebody who doesn't have decent knowledge of it. It's not voodoo or anything, you just have to at least know the rules of thumb for setting it up. Honestly, he probably just threw fuel at it and gave it back to you.

 

I live near you and run 13 to 14psi daily on stock twins. Of course I am weird and only fill up at one certain gas station. I don't mean to down talk companies but no one around here is that great at rotaries. you choices are fly someone in or learn yourself.

 

Well he's definitely not gonna blow it up in the mid 10's >_>. It sounds like the tuner just didn't have enough experience in tuning a rotisserie so he just tuned it overly conservative so it wouldn't blow up. Your plugs are gonna foul sooner and probably carbon up your motor over time.

There is nothing wrong with 10% ethanol, 92 octane is 92 octane. It just might not make as much power (hardly noticeable).

thewird

 

looks like your in luck, well kinda you gotta pay for a second tune but he seems to have a good rep going for tuning.

https://www.rx7club.com/nw-rx-7-forum-33/tuning-session-brian-bdc-853481/page2/

 

Awesome! Thanks. Ok so hopefully I'll get a tune by him and be able to come back and post up some better numbers.

So what kind of power numbers do you guys think I should be making? About 350 or so with 15 psi?

 

that sounds about right. look forward to seeing your results.

-Chance

 

350 at 15 psi on stock twins, those BNRs should do better than that.

 

What he said. I made 310 rwhp on 91 octane CA **** water - I mean gas - last year. Large street ported motor and 99 twins and the usual bolt ons including an SMB high flow cat. At 15PSI, the motor made 350 rwhp. Steve Kan tune.

This is the motor for sale in my sig fwiw.

 

I know your BNRs are seq, but I made a solid 350 rwhp at only 12 psi with my non-seq BNRs on the rx7.com dynojet back in like 2003.

 

Rich dyno numbers don't mean a lot. I had to blow my engine at 18 PSi with 12 AFR to get 330 rwhp on a street port on a Mustang dyno. Later with a bigger street port and intake manifold porting I made the same power with safe 16 PSi @ low 11 AFR. This was with sequential BNR's.

Then with the 500R-SP I had to push it to 18 PSi with mid 11's AFR's to get 415 rwhp.

It all depends what dyno you go to and going to the same type of dyno doesn't always mean you'll get the same numbers.

thewird

 

+1 dont get to caught up on the numbers, I only made 317 on a dyno dynamics but have beaten a few cars and held with some that I shouldnt be with my power.

 

Also to note, my car used to keep up with single's when I had my BNR's and now it just runs away with the new single. It's just a number coming from a machine. Don't expect a certain number. If it has the right fuel and timing at a certain PSi level, its not going to make more power in the hands of another tuner unless he puts it on the edge or uses a different machine or even ambient weather to his advantage with corrections.

thewird

 

\/

Agreed.




I've never really understood why people say that going non-seq will increase HP over sequential twins in any large capacity. Does making the conversion really free up anything more then perhaps 10whp?

 

So it sounds like I should be in the 11's AFR-wise. Would getting a retune to lean this out produce more power? I figure bumping the boost will, but what about leaning it out to where it should be?