Red99TA

iTrader: (11)

^good point - what was the DC of these stock injectors on the dyno? I didn't think it was a good idea to run stock LS1 injectors on a H/C/I car.

nastychevelle

iTrader: (7)

according to post #26 they arent maxed out which i find hard to believe on a H/C/I car

Droptoplt1ta

Yes, the Tuner told me the stock injectors were not maxed out. Remember the 98' LS1 has 28 LB injectors stock. I found specs on the 97-98 Patroit heads:

Combustion Chamber: 67cc
Intake Runner: 220cc
Exhaust Runner: 67cc
Intake Valve: 2.02"
Exhaust Valve: 1.57"
Max. Valve Spring Lift: 0.650"
Spring Pressure Closed: 135 lbs. @ 1.800"
Spring Pressure Open: 375 lbs. @ 1.090"
Retainer Material: Titanium
Valve Seal Material: Viton
Valve Guide Material: Manganese Bronze
Valve Job: 5-angle


So the intakes are 220 cc

https://www.patriot-performance.com/...&cat=36&page=1

Droptoplt1ta

I just ran the car at the track again.... Same low 106 MPH....

This time I ran at Milan dragway (much better than Lapeer)


Run 1 Run 2
60ft: 1.76 1.93
1/8 ET: 7.8 8.1
1/8 MPH: 87.5 87.1
1/4 ET: 12.40 12.76
1/4 MPH: 106.8 106.3


I cleaned the air filter between this trip at the track and the last time as well as checking all of the TR55 spark plugs. They all looked great and I reset the gap at about .52

There was an LS2 GTO there, M6 with heads and cam. STOCK LS2 intake and he ran 12.1 at 117 MPH - So I dont think my ported LS2 intake is the problem.

My guess is the problem is either the tune or the Fuddle converter. I am sure it is one of the two.....

allngn_c5

iTrader: (3)

Hey man, I knew I had seen your threads. Very cool meeting and talking to you last night !!! Best of luck with getting your car to trap better. For a h/c car she's a little slow, but as soon as your TC issues and tune are sorted out you'll be doing much better. FWIW man, all the waiting we did last night was worth it for those that waited until the end. We were almost hot lapping. I got 3 runs in, in less then 1 hour !!! Best trap was 126.72, don't ask the et (11.98) my 60 skills suck *****. Oh well, next time.

MNR-0

Change one thing at a time

Use HPT or EFI to measure converter slip - that STR should yield no more than 6% slip at 6000rpm (a stock converter yields 2% slip). That will tell you if the converter is bad

Then, look at the manifold vacuum at WOT. If it's less than 99kPa (100kPa is ideal) then you have intake restriction issues (head, TB, MAF, intake)

If it still doesn't make the power, the converter is efficient and intake is all good, dump the pipes and do an open header run on the dyno

If it still makes no difference, then look to the engine. Do a leakdown test on each cylinder

Your car is telling you what is wrong with it. You just gotta know where and what to look for. Changing parts without any idea of cause keeps your tuner/workshop happy but you out of cash

Sid447

@370rwhp (Mustang dyno)

the stock 28lb injectors are maxed out.
A few people have mentioned it already.
I was over 90% at hi rpm with less rwhp (360) checked and confirmed by numerous EFI-L logs.

Your other problem may be your tune. A 227/227 on a 114LSA should be peaking a lot higher than 5,200-5,400rpm.