question about duty cycle.
06-08-2005, 10:43 PM
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question about duty cycle. I have a 99 ws6. mods in sig. I had heard that the stock injectors(26 lbs in 99) would be good to 400 rwhp. A couple weeks ago I dyno'd on a dynomax(compareable to a mustang dyno) and put down 355 to the wheels 
, unlocked converter, but my stock injectors were at 100% duty cycle at wot at 5600 rpms and above. I upgraded to 30 lb injectors and the duty cycle dropped to around 80%. So I guess I ran out of injector, but why at such a low hp figure? I know that autos dyno higher with the converter locked, and the shop told me that dynojets dyno about 10% higher so does that mean I may have 400 rwhp on a dynojet with a locked converter? duty cycle DOES rise with hp right?
, unlocked converter, but my stock injectors were at 100% duty cycle at wot at 5600 rpms and above. I upgraded to 30 lb injectors and the duty cycle dropped to around 80%. So I guess I ran out of injector, but why at such a low hp figure? I know that autos dyno higher with the converter locked, and the shop told me that dynojets dyno about 10% higher so does that mean I may have 400 rwhp on a dynojet with a locked converter? duty cycle DOES rise with hp right? 
06-09-2005, 10:00 PM
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Originally Posted by nasty99WS6
I have a 99 ws6. mods in sig. I had heard that the stock injectors(26 lbs in 99) would be good to 400 rwhp. A couple weeks ago I dyno'd on a dynomax(compareable to a mustang dyno) and put down 355 to the wheels , unlocked converter, but my stock injectors were at 100% duty cycle at wot at 5600 rpms and above. I upgraded to 30 lb injectors and the duty cycle dropped to around 80%. So I guess I ran out of injector, but why at such a low hp figure? I know that autos dyno higher with the converter locked, and the shop told me that dynojets dyno about 10% higher so does that mean I may have 400 rwhp on a dynojet with a locked converter? duty cycle DOES rise with hp right?
, unlocked converter, but my stock injectors were at 100% duty cycle at wot at 5600 rpms and above. I upgraded to 30 lb injectors and the duty cycle dropped to around 80%. So I guess I ran out of injector, but why at such a low hp figure? I know that autos dyno higher with the converter locked, and the shop told me that dynojets dyno about 10% higher so does that mean I may have 400 rwhp on a dynojet with a locked converter? duty cycle DOES rise with hp right?moving some serious air. Have you checked fuel pressure after 30svo's?
It proves that Stock injectors are inadequate. How did car run after the in-
jector change? You should be able to tell the difference.
06-10-2005, 04:28 AM
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The tuning tule was hptuners, and no I did not check the fuel pressure after the 30 lbers were swapped in. The horsepower figure didnt change after the swap, but yeah, the car feels alot better on the street. I am getting it dyno'd 6/13 on a dynojet. we will see what a difference a dyno makes, I guess.
06-11-2005, 04:30 PM
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Originally Posted by nasty99WS6
The tuning tule was hptuners, and no I did not check the fuel pressure after the 30 lbers were swapped in. The horsepower figure didnt change after the swap, but yeah, the car feels alot better on the street. I am getting it dyno'd 6/13 on a dynojet. we will see what a difference a dyno makes, I guess.
w/30#svo's are pretty close to 80%. Mine's a m6 and I'm over the 400hp so
should be no problem w/yours.
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06-14-2005, 02:55 PM
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Originally Posted by stang killer
My car makes 400/395 to the wheels and my injecotrs are at 105% right now.
i know iknow. but anyway, they told me the correct number, had it been run in 3rd, was 374 rwhp. 30 lb injectors will be good for awhile i suppose. 
06-14-2005, 09:48 PM
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Originally Posted by RedHardSupra
internet myths suck. if you don't measure it yoruself, you will never know the truth.
i got up to 109% DC on stock 99 injectors on a really minimal setup, now i'm up to 85% DC on svo30s with 363rwhp
i got up to 109% DC on stock 99 injectors on a really minimal setup, now i'm up to 85% DC on svo30s with 363rwhp
06-14-2005, 10:48 PM
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i have stock injectors but i have a 6spd ws6...my fuel pressure is higher than yalls..at least thats the rumor..I have measure my fuel pressure and I'm running 48psi and i have the stock injectors dynoed 374HP and 396TQ...duty cycle is 73% ONLY because i leaned the car out and turned off the cat converter protection that was causing my car to go rich at WOT. before leaning my car out my injectors were running 82%. they say to stay under 80% duty cycle to stay safe(not go static)..but whatever.
I'm getting ready to to hook up an air to fuel gauge and find out exactly what I'm running. On the dyno i was going from 13.4:1 to 12.1:1 at high rpm..that has changed now..I'm running about a 13.0 at high rpm
I have 32lb/hr injectors sittin in the garage waitin to be installed and i'm not going to get those in until i do a cam swap
I'm getting ready to to hook up an air to fuel gauge and find out exactly what I'm running. On the dyno i was going from 13.4:1 to 12.1:1 at high rpm..that has changed now..I'm running about a 13.0 at high rpm
I have 32lb/hr injectors sittin in the garage waitin to be installed and i'm not going to get those in until i do a cam swap
06-15-2005, 06:45 AM
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Originally Posted by ZL1Killa
...my fuel pressure is higher than yalls..at least thats the rumor..I have measure my fuel pressure and I'm running 48psi