Yup... another "is ??psi safe" on 91 octane thread


setup..
Pettit rebuilt 13B 3mm seals
Large streetport
1600 secondaries, stock primaries
all fuel/ignition supporting mods
T04R (T67) 1.00 A/R
HKS Standard wategate with 12psi spring vented to atmosphere
Apexi AVCR boost controller

Right now on 2nd and 3rd gear pulls i boost spike up until 1.22bar (17.5psi) around 50 times in a 3 month period. Wastegate lines arent setup right which cause the spike, but its not that bad. Everything holds up, see nothing wrong.

Now, since I boost spike to 17.5psi and so far it seems safe... should i go ahead and tune for 17psi or 16psi?

My FD is not a DD but at times used as one, so im looking for some reliablity.

Just want some discussion on 17-18psi on 91 octane with my setup... since everything has been good so far, and Steve Kan tunes for that, I dont want to blow something 6 months down the line.

 

I'm running 1.5 bar, 22psi on 90 octane but on a 8.5 comp rotor motor. I
run 11.5 plugs exclusively- I think this is the key. I do 4th gear pulls and
100+ mph runs almost daily= no probs for 2 years now. Car makes around
500+whp on a 67 mm[t04 z] turbo at this level. I think there is room for
more but this is more than one needs for the street- car is ridiculuosly
fast and more fun than my 10sec cobra mustang.

 

Can you find the model number of the plugs?

 

They're probably the NGK or Greddy racing plugs, 11.5.

This question comes down to two camps, and many will say they run lots of boost on pump gas.

I'm more conservative than that, and run as high as 19 psi on 93 octane only because of my Aquamist setup. Before that, I tried to stay around 15 psi on 93.

To answer the question in your subject, i'd say 'No.' Unless you have a damn good tuner and everything optimized, I'd say you're nuts to even try.

 

Im pretty sure Steve Kan is in the "damn good tuner" category (although theres a huge debate about that -__- ) he tends to stay on the conservative side.

Anyone got a link for the NGK racing 11.5's?

I think im just going to go with those and stay at 17psi.


btw.. Rich... what tires are you running in your sig? haha

 

if it's spiking late then that's probably why everything has held together. coming after peak torque it's not so bad, but if you set it up to immediately hit and hold 17psi then things can be different. you can definitely tune to that and possibly be ok but there are a lot of factors in that to make it "reliable". hahaha

 

Steve is a super-conservative tuner, and I mean AFR's well, well, well over where they could be. The timing is never precise as well... but it's fairly close. Steve's a great guy... however, I was able to free up 50-75hp after altering his map and it was still rich and just as safe. Steve is VERY conservative...

I ran 24PSI on 91 octane... engine ran strong, and didn't have any detonation issues until I hit a barrier which tanked the motor. However, I'll be using AI for this setup just for the added cooling properties, etc.

 

I run 17 psi on a very similar setup to yours with 91 octane. It worked fine just running all 9's for plugs. I put some 10.5's in there b/c I have them.

Then I got AI... .

 

I've done it on 93 octane here on the east coast for a long time, many miles with no problems with #9 plugs, it's all in the tuning. Go really rich with conservative timing for pump gas on the street to be safe.

 

BFG G Force KDs. Not bad tires, but they're old technology at this point. I'm switching to something else with the new Fikses......

 

Holy **** 24psi without AI.

This might give me incentive to run 18psi since Steve tunes conservative anyway.


and Rich... those look DAMN good... how'd you get the high gloss look especially on that actual tire (not the wall)

 

I wouldn't run that kind of boost even on 93 without some kind of alky injection or something.

In your situation, well, it works until it stops working. And then you go boom. It could be any random situation that makes it pop.

 

His special sauce

 

 

Wait wah? haha

 

BTW.

does anybody have any good setups on how to install aquamist 2d water injection?

 

Wrong section. Wrong thread.

https://www.rx7club.com/search.php?searchid=4588728

 

I dont know whether to run the NGK 10's, 11's or 11.5's. Im thinking I should go for 11 since its in the middle.

Pros? Cons?

I need to order them soon... Kan is tuning this weekend


also.. anyone have part numbers for the plugs?

 

What boost are you shooting for?

Up to and around 1 bar, 9s are ok. approaching 20 psi, you'll want 10s. The higher the number, the quicker they'll foul on you during street driving.

I don't know the part #s offhand, you can order them from rx7.com, I'm pretty sure they stock them.

 

I guess ill go with 11s, maybe 10s.


Can I run 10s or 11s all around? Or specifics for trailing and leading?

 

Technically you want to run a colder plug in the trailing, ie 10s leading and 11s trailing. You can run all the same though, that's what most people do.

 

Looks like Ill go with the NGK Racing 10.5's for 17-18psi

 

To the OP:

I just chipped a seal running 17lbs @ 10.6 AFR's (SUPER RICH!) on 91. To keep the story short, don't go any higher than 16-17lbs on 91 unless you're running AI. Here's a post I did on another site if you want more info:

http://forums.thecarlounge.com/zerothread?id=3633017

Oh! Are you running on the 2 bar map sensor?

 

I have a GM 3 Bar MAP sensor and 3mm 2 piece apex seals, not to worried about breaking an apex seal but will take that into concideration.

Specs on your engine? Rebuild? Original? 2mm, 3mm apex seals?...

 

Street-port, 2mm (atkins), dowel pin-job, single turbine (.70Front, .68 rear), full 3" exhaust, greddy FMIC, PFC, koyo rad, MSD, all 9 plugs, GM 3-bar, etc... But I've learned my lesson, definitely no big boost on Cali fuel without my AI. It's too much of a risk especially with the quality of Cali's 91 AKI to begin with