Hi there. Me and a friend of mine will go to a dyno next week. I've no idea about the results, but how many hp do you think I'm running in my FD now? Do you think I can go over 300? It's pure curiosity, in fact...
My mods are next:

Pettit Racing unlimited ECU
Greddy profec B---- 13 psi
HKS downpipe
Bonez hi-flow cat
Greddy titanium catback
Apexi power intake
stock IC

 

275 ish, I'd think...what kind of dyno? That matters...I'm used to mustang dynos and those generally read lower.

 

IMO, don't go over 10 PSI with the stock IC. Regardless of the ECU, if your charge temps increase too much; you can create a situation which detonation can occur.

Tiny/stock IC + increased boost + sitting on a dyno without decent airflow = not good.

 

Yeah, I always laugh at some shop's dyno cooling systems...yeah, that oscillating fan will simulate 100+mph wind speed LOL.

 

i got my car tuned... i have close to what you have... and i put 276hp at 12 psi with 270 t....he said if i would have thos i would of broken 300....but i would recomend getting bigger secondary injectors, an ignition system and ic.. with that hp im running 94 % injector duty... which is really bad so iv been babying the car till i get them...

 

I made 280 rwhp with stock injectors, stock IC, stock fuel pump (it was very shaky though), Apexi intakes, downpipe, no emissions (all blocked off), high flow cat and Apex N1 cat back with a Power FC.

Went quad 850s (this is a really inexpensive upgrade - used 850s from this forum (often free) and the milled fuel rail from Gotham ($100.00)), Supra fuel pump, and the XSPower SMIC and made 320 rwhp. without really working at it. Now with shitty street tires I can consistently run 13.3 in the quarter mile.

 

Whaat? It's supposed that you can happily run 14 psi on stock fuel system with pettit racing unlimited ECU. I'm running only 13, and my A/F meter always points in the rich zone (although it's not a wide band). Do you say that maybe I'm running in the dangerous zone??

 

https://www.rx7club.com/showpost.php...4&postcount=25

 

In addition to having a stock intercooler, you also have no ducting to it which makes it even less effective. So that's one reason for concern about your charge temps.

Plus most stock injectors will not run safely above 12psi. The duty cycle is just too high. While it's very good that your wideband indicates safely rich, I agree that going over 12psi is not the safest thing to do. If you follow the link to the whole thread that Mahjik provided (look to the upper-right of the screen) you'll get all the details.

 

I disagree with that as people have been running 13-14 PSI on the stock injectors for years without issues (using M2 and Pettit ECU's). Talk to RTS3GEN who put down 359 rwhp on stock injectors (ported motor) years ago (and still runs the same setup today).

 

he said he doesnt have a wide band all he has is an a/f meter.. thos arent always right...
Mahkijik wouldnt running the stock injectors with that much hp cause the inj to work more at about 90-100% and wouldnt they end up (like iv read) heating up and either getting stuck closed or open?

 

Read Wade's post. There is more to it than just "high duty cycles. Here's a thread where it has hashed out again:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/what-situation-do-you-have-259912/

As far as injectors heating up and getting stuck, the fuel cools them (as it's not that hot flowing through there). Once again, guys have been doing this for years. It's not a new concept, people are just too paranoid these days.

 

I think it makes no sense that Pettit or M2 claimed that you can safely run 14 psi with these ECU's and stock fuel system. I did a full search before buying this ecu and there's a lot of people running these high boost levels for years and without problems...

 

Would you be willing to run 13-14psi without a wideband, without monitoring charge temp, and using an unducted stock intercooler?

I think that both approaches can be well justified. But if something is out of whack at 13+ psi and you don't have those extra monitoring sensors and better intercooling you won't know until it's too late. Since I recall the Victor doesn't have a lot of tuning options where he is, I think the conservative approach is the best fit. 12psi is a level the stock system can pump out all day on every car.

Dave

 

In his situation above, I already stated he should not to run over 10 PSI. However, in the case of having a proper intercooler and the proper conditions, sure I would run 13-14 PSI using the Pettit ECU on the stock fuel system without monitoring A/F and charge temp. Did it for years.



There is the conservative approach, and then there are facts. This statement "Plus most stock injectors will not run safely above 12psi." is not quite true. The stock injectors have been proven to run much higher then 12 PSI without issues. That was my issue with your statement. Now if you want to say that with his *current* setup, it isn't advisable to do so; that's something else. But I want to make it clear that it's not required to have larger injectors or a PFC to run higher than 12 PSI. That is a fallacy which has plagued this forum for the past few years.

 

In fact I am about to buy an ARC smic with a pettit air duct. Maybe it would be better to keep 12 psi until I got my new IC...
Which is the best way to monitoring charge temps? Is there any kind of gauges for this?

 

It would be best to keep at 10 PSI until you get a better IC. IMO, I wouldn't bother trying to the charge temp unless you just want to be **** about it. If you end up going the route of getting a programmable ECU and doing your own tuning, you'll most likely either have the capability already in the ECU (like the PFC) to monitor the intake temp or you can add it on at that time.

 

OK Mahjik, I'll keep boost at 10 psi until I get my new IC. That's a thing not to play with...

 

Yeah, all the good info has been covered...+1 for upgrading your IC.

However, I'm having my car dyno tuned with a PFC on Sept 1st @ 12-13 psi, so let me know how you make out. Good luck!

 

Chris @ RP (RX7.com) conservatively tuned mine at 11.5 psi (since one of my big issues was normal daily driveability). I have most of the typical bolt-ons, but have yet to add the bigger IC and/or 850 primaries. A local F-body club sponsored a dyno day recently so I went. Expecting to throw down around 275 horses, I was pleasantly surprised to hit 299 HP on the first dyno run. Even gained a lot of oohs & ahhs in the process, too, since most of the other cars were either Mustangs, Camaros, or T/As. Interestingly, a 2006 GTO threw down 353 HP with only CAI upgrade. Not bad at all.

My mods include: Street Port Motor w/ 3mm Seals, '99 Spec Twins, Cold Air Intake, Bonez HF Cat & DP, Racing Beat Dual Tip Exhaust, Power FC @ 11.5 psi, & RP Fuel Pump upgrade.

Btw VictorFD, I'll be in Barcelona for a couple of days next month for my holiday. Thinking about staying in El Born or the Gothic Quarter. Which is better in your opinion regarding trendy hot spots for meeting friendly 'chicas bonitas'? I'm assuming I can't go wrong in either location. Also, will FC Barcelona be playing any exibitions in mid-August; specifically, 16-17 Aug? That would be so kewl to catch a futbol game while there. Muchas gracias & best wishes on your dyno day.

 

I ran the following mods on my last car....

M2 CF airbox
M2 dp
M2 STAGE 3 ECU
RB dual
Blitz or OEM smic

Boosted 13-11-13 all day long on COMPLETELY STOCK fuel system.

No issues whatsoever. Engine was still at about 9's all the way around on compression when I sold it.

 

What ?!?!?! All that power and you're only running 13.3 ???? I don't care how bad your tires are or how good/bad a driver you are... that just doesn't sound right.

 

how much does a stock fd make at the wheels? Im just curious what my jdm with zorst and filters makes?

 

Around 220 rwhp.

 

You don't need the pettit duct for the ARC unit. I had the ARC on mine, and it matches 100% perfectly with your stock duct.