so, now that my car is not breaking up under boost (improper gap on plugs, .40x1, .36x2, .34x2, and .30x1, break up was most likely blow out at higher boost on that .40 plug, and a little on thos .36's), what is the norm for boost upping?

i know on stock SR ECU's, people run between 12-14psi on stock injectors, tune, maf blah blah blah...

SO, since a stock SR is at what, 7psi? and people are jumping to just over ten, would that mean that since my car is tuned at around 13psi, i can run it up conservatively at 16.5psi, give or take .5psi?

i mean, it's only a 3psi jump... at 13psi, my AFR's read around 11.5/6, did a 16psi pull and it read like 12.0-1... i know target AFR's are 11.5/12.0 at full boost WOT, and 14.7 cruising...

now, my car, at 16psi is at 12.1, holds pretty steady, maybe drops to 11.8/9 in the mix... so to me, from all outward appearances, that's safe right? or am i pushing the limits with timing as well?

i know my tuner usually does boost increases in incriments on the dyno, and adjusts per boost level accordingly, so just a 3-4psi jump shouldn't really be all that bad right? considering that a lot of people running SR's, myself included, have ran 5psi+ over stock tuning...

i prob already know the answer, but i'd like the people here who know what the hell they're doing to chime in.... just to confirm or debunk my ideas here...

thanks in advance...





oh, and also, if the car made 416whp @ "14.3PSI" (not proper as that's what's displayed on the Blitz SBCid with the WG function on), and it made 408 @ 14.0psi, would that in effect mean that for every .3psi, i gain/lose 8whp?

 

I'd run 16 psi all day.
I doubt you're going to melt a piston or anything like that.
Just pay attention to it for the next couple of weeks and see how it holds up.
I've heard of them running 20 pounds on all stock everything.
If it is a major concern then run the lower boost level most of the time and only bump it up when you want to flog on it occasionally.

Not going to be that long till you're back on the dyne anyway, and you can get it tuned better then.


as for your whole .3 psi = 8 whp.
I'm sure it will work out that way for a little bit, but once you start getting passed a few more pounds of boost, it is going to take a lot more to get that same 8 hp increase. the higher the pressure, the worse the heat gets. Then add in how the volume of air changes. (think bigger turbo, less boost making the same power as a small turbo boosting more) and all of the rest of that smart mumbo jumbo and your psi to whp ratio starts to get smaller.


but then again, I broke a shoe lace, dropped a fortune cookie, broke the salt shaker, spilled some milk, over dosed on cold meds, and have no pain killers for my knees, shoulder, lumbar and spine. So I'm about one stale oreo from being at the point of just saying fuck it, twisting the boost controller knob till it breaks off, and proceeding to drive with the throttle mashed to the floor for as long and as far as that pending time bomb would take me, So I could be totally wrong.

 

The motor will probably hold whatever you throw at it (as long as the mixture is right and timing isnt too aggressive)....HOWEVER

you really, REALLY need a way to monitor knock and injector duty cycle. That takes all the guesswork out of it. I know on my DSM...it likes 11.5:1. It runs even better at 11.8:1. But then as soon as it gets to 11.9-12.0 I start to see about 5-8 counts of knock. If that happens over and over again at high rpm thats no good...

Are you on the stock 440s? What do you tune with?

 

thanks emp... and you're right, if i don't sell the car, she'll most likely be seeing the dyno for the third time in the next month or two...

omgosh, i'm running 550cc RX7 injectors, T71 turbo, 4" Trust FMIC, AEM EMS stand alone, 3.5" exhaust, cams, tubular manifold, etc etc... Tuned by Martin of ZFever/RS Enthalpy.

i just got back from some fun running, did a second gear pull all the way to 5th, got her up to 240kph (150ish), then went into 5th (then a FHP whipped it around, and i dropped it back in 4th and hammered it)... she pulled pretty solid the whole way, AFR's never went any leaner than 12.0, my "copilot" said it was pretty steady 16psi, was more around 15.8psi till it started creeping near redline (small 38mm wastegate), so i'll need to adjust the Blitz SBCid to where it pegs out right at 16.0... the AFR's were averaging around 11.8, give or take .1... copilot also noted there was no detonation that he could hear... i mean, from my exp, it pulled all the way to red line flawlessly, no odd noises, surging, nothing, just the open dump WG swishing and screaming, and the exhaust roaring out the back...

talked to a local guy at the "track" and he confirmed as well, that a minor 3psi increase over what the car is tuned for isn't anything major, he mostly deals with RX7's, has had a bit of exp with RB's as sullivanracing06 is the OG RB guy in town, and he's done some tuning on his car... so at this point, i'm feeling pretty comfortable with 16psi...

 

Good enough of a test for me.
lol

 

marshal, you think wayyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy to much about this kind of thing......


or do you do this to get your post count up?

hmmm lol

 

naw, you know me man, i think too hard...

 

you need to talk to your tuner an figure out why you cant step your boost up, you might be held back by not having enough fuel, bigger injectors are a must, might not have enough fuel pump to go up in hp. you have aem so the sky is the limit for tuning, you need to get some 1000cc's and a retune, if plugs are blowing out gap them down, what is your option for running colder plugs? 400 hp 6cyl is pushing a walboro, might have to consider fuel pump options, a dual intake setup or 1 in tank and a inline pump for insurance.

 

i have 550's, and they suit my needs for now, although i've been considering 1k's for a while now..

 

do you know what duty % they are being used at? 80% is the #. anything more than that an you need to step your injector game up.