Interesting data from bolt on LT1 data run

[prorac1]

I ran some data logs on the Camaro SS the other day. Other than some part throttle knock retard (time for an LT4 knock module) everything worked well. Mods on motor are; LT4 valve springs, 1.6 RRs, BBK shorty headers and Y pipe, no cats, Flowmaster American Thunder Cat Back, Arizona Speed and Marine CAI, Under drive pulleys on crank and alternator, No egr, or air pump, and thats it. It has the stock injectors, TB, elbow with donkey schlong, and maf. From research ive done most people didnt think that stock long block LT1s would max out the stock injectors, but heres something interesting. My injector duty cycle reached 85-87% at one point. From doing a search on the camaro board a lot of people say that over 80% duty cycle is when you should look at increasing injector size and tb size. Any other input on this subject would be appreciated. Im AMAZED that with my set up my duty cycle is that high, but im glad that I have kinda a freak hp wise. In my last car this same long block and mods ran 12.81 @ 107 mph. IMHO thats crazy mph for a bolt on full weight (3600 lb) car. Any input is appreciated. Is it time to go with bigger injectors and TB? Thanks Eric L

[DETROITMUSCLE]

IMO that mph isn't crazy, that is bone stock LS1 trap speed which I guess for an LT1 is pretty damn good. As for the injectors how old are they and have you ever had them flow tested? If they are clogged that might cause them to increase duty cycle because the car is leaning out? This is just a guess.

[prorac1]

The car deffinately isnt leaning out, it seems to be running a little rich which will also effect duty cycle. No, the mph isnt insane, but for a flowmaster cat back, shorty headers, etc. Its pretty good. The injectors were cleaned last year, but have never been flow tested. Not that they are very accurate, but acording to a couple of hp calculators, that et and mph with my weight at that time equals out to 325 hp at the wheels, which to me sounds unrealistic for my mods, but the et and mph dont lie. Who in the state/area can flow injectors and what does it cost? Thanks for the input man. Thanks again, Eric L

[Phantom409]

I have a set I sent to SLP that I had cleaned and flow matched if you are interested.
Have paper work.

--Double post auto merged--

I spent 100.00 on the ones I had done.

[prorac1]

What size are they? I have a set of 42lbers sitting in a box that i ran with the blower, but i feared that they were to big and that i would run into pulse width problems, so i put the stockers back in. Thanks Kyle, Eric L

[DETROITMUSCLE]

well if that is the case then put some bigger injectors in that bad boy, but to be honest I think you'd be just fine running that duty cycle on a bolt-on car.

[JoeliusZ28]

Where are you logging your injector duty? Ive been trying to find that on datamaster.

I trapped 104-105 with my car when it had just headers, cutout, CAI and a clutch.

[steve40]

this place is near i-75 and 696, can clean and flow injectors

http://www.cprracing.com/serv01.htm

but where your car is, your fine at that duty cycle. if you are doing a cam or spraying in the future, then going to a bigger injector is needed.

also, save your money for something other than a tb. i went to a 52mm and it did absolutely nothing performance wise....only time it benefited me was when i ported the heads and put a cam in the motor

[WMCCjames]

You are just fine with that injector duty cycle as long as it's for brief amounts of time. My stock LS1/M6 hits 100% on a 1/4 mile run rght before a gear change.

[prorac1]

Thanks for the input guys. I am using datamaster version 3.4.1 and its in the normal charts. Under inj DC (calc). If you want, leave your email address and ill send you the data log in question. Im not planing any heads or cam for the next couple of years, so thats kind of what i was thinking also, for brief ammounts of time, it should be ok. Thanks again, Eric L

[prorac1]

Yeah but remember Joel, that was when I had a TH350 and 3800 converter. Big converters suck hp. I also have BBK shorty headers and at that time no cut out, so this was all through a flowmaster cat back. You know, all the parts that people say wont make horse power, lol. Makes me wonder how much I would gain with long tubes? Eric L