knocking on n20....
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yeah... or cbodnar 
for a 75shot run a 42nitrous/26 fuel jet. if i were you when i ran the 45wet shot on gm stg2 + 2.80 pulley on stock exhaust and stock header/dp i used to run a 36nitrous/22fuel. i think that was like a 45shot. pm me if u need help or guidence i'll try to walk you along as best as i can
for a 75shot run a 42nitrous/26 fuel jet. if i were you when i ran the 45wet shot on gm stg2 + 2.80 pulley on stock exhaust and stock header/dp i used to run a 36nitrous/22fuel. i think that was like a 45shot. pm me if u need help or guidence i'll try to walk you along as best as i can
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Hm.. I have a 40 nitrous jet in there and a 22 fuel jet for a 75 shot.. I'm running lean and having BAD knock..
I have a 28 nitrous jet from my 35 shot (which I can use as a fuel jet along with my 40 nitrous jet)
Just to test it out..
Would it hurt to run this much fuel with a 40 jet?
What shot would this be and most importantly.. Running rich like this wont hurt it right?
I was thinking of running this 40/28 combo and testing how bad I knock if any at all..
Damien what are your mods other than juice and what are your jet combos and what shot are you running?
Do you know if you're knocking/running right.. Etc?
Would it hurt to try this 40/28 combo?
I have a 28 nitrous jet from my 35 shot (which I can use as a fuel jet along with my 40 nitrous jet)
Just to test it out..
Would it hurt to run this much fuel with a 40 jet?
What shot would this be and most importantly.. Running rich like this wont hurt it right?
I was thinking of running this 40/28 combo and testing how bad I knock if any at all..
Damien what are your mods other than juice and what are your jet combos and what shot are you running?
Do you know if you're knocking/running right.. Etc?
Would it hurt to try this 40/28 combo?
Last edited by ChriSS/SC; Sep 2, 2009 at 07:11 PM. Reason: Automerged Doublepost
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From: NY
i run a 42nitrous/26fuel.
if i were you on stg2 i wouldn't run that big of a shot but oh well. since you already are going to then run a
40/28 and see how that works out. should hopefully fix your problem. good luck & get a wideband please
if i were you on stg2 i wouldn't run that big of a shot but oh well. since you already are going to then run a
40/28 and see how that works out. should hopefully fix your problem. good luck & get a wideband please
37/22 for a 50 shot.
40/24 for a 75
44/26 for a 100
basically speaking. Jet's aren't the exact same size every time, so you might have to play with it a bit. I'm guessing on the 100 shot numbers, I believe holley actually calls for a 46/30, but that is for 42psi fuel pressure, where we see almost 60. Thats why you can run the 24-25 on a 75 shot and the 22 is actually a bit big for a 50 shot, but rich is safe.
Get some bigger jets, you can order them from Jegs/summit for under $8 each usually and if you get a couple, the cheaper price makes it worthwhile. You can also get whatever size, stores usually skip every other one to reduce inventory and stocking hassles. Or step your nitrous down to a 36-38 jet and see if it improves. You could also lower bottle pressure to nig-rig and see if it changes, but only as a test measure.
40/24 for a 75
44/26 for a 100
basically speaking. Jet's aren't the exact same size every time, so you might have to play with it a bit. I'm guessing on the 100 shot numbers, I believe holley actually calls for a 46/30, but that is for 42psi fuel pressure, where we see almost 60. Thats why you can run the 24-25 on a 75 shot and the 22 is actually a bit big for a 50 shot, but rich is safe.
Get some bigger jets, you can order them from Jegs/summit for under $8 each usually and if you get a couple, the cheaper price makes it worthwhile. You can also get whatever size, stores usually skip every other one to reduce inventory and stocking hassles. Or step your nitrous down to a 36-38 jet and see if it improves. You could also lower bottle pressure to nig-rig and see if it changes, but only as a test measure.
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37/22 for a 50 shot.
40/24 for a 75
44/26 for a 100
basically speaking. Jet's aren't the exact same size every time, so you might have to play with it a bit. I'm guessing on the 100 shot numbers, I believe holley actually calls for a 46/30, but that is for 42psi fuel pressure, where we see almost 60. Thats why you can run the 24-25 on a 75 shot and the 22 is actually a bit big for a 50 shot, but rich is safe.
Get some bigger jets, you can order them from Jegs/summit for under $8 each usually and if you get a couple, the cheaper price makes it worthwhile. You can also get whatever size, stores usually skip every other one to reduce inventory and stocking hassles. Or step your nitrous down to a 36-38 jet and see if it improves. You could also lower bottle pressure to nig-rig and see if it changes, but only as a test measure.
40/24 for a 75
44/26 for a 100
basically speaking. Jet's aren't the exact same size every time, so you might have to play with it a bit. I'm guessing on the 100 shot numbers, I believe holley actually calls for a 46/30, but that is for 42psi fuel pressure, where we see almost 60. Thats why you can run the 24-25 on a 75 shot and the 22 is actually a bit big for a 50 shot, but rich is safe.
Get some bigger jets, you can order them from Jegs/summit for under $8 each usually and if you get a couple, the cheaper price makes it worthwhile. You can also get whatever size, stores usually skip every other one to reduce inventory and stocking hassles. Or step your nitrous down to a 36-38 jet and see if it improves. You could also lower bottle pressure to nig-rig and see if it changes, but only as a test measure.
After that though.. I'm gonna try maybe a 40/26 or 40/24 depending on my fuel needs..
You're right about the fact that you kinda of have to play with it a bit..
75 should be fine on stock motor, correct?
I can see how 100+ might push it on an LSJ potentially but I see no problem with a non-knocking 75 shot down the road.... Any reassurance on that in your opinion?
Last edited by ChriSS/SC; Sep 2, 2009 at 08:14 PM. Reason: Automerged Doublepost
If you are stage 2+ , stay with a 50 shot. Traction will be more of a problem than power if you've done your modding correctly. 3rd gear wheelspin on street tires for me.
If you are true stage 2, meaning 3.07" pulley and GM tune with 20+ degrees of timing, you can run a 75 shot at max, but it is pushing it. My advice is get a tune if you run more than a 50 shot.
If you are stock pulley/tune, you can easily get away with a 75 shot untuned, or 100+ tuned (stock timing numbers can be in the 28deg range, way too high for nitrous).
I've done up to a 90 shot on stock bottom end with no problems whatsoever as long as it was tuned to be safe. A 75 shot on stock internals with stage 2 timing maps and a smaller pulley WILL break something, i've done it, as have others locally and on here. Be careful.
Final thought, be SURE of your shot, find someone who has some knowledge and ask them about jets, or call the company that makes your kit, they can tell you exactly what the jets are rated at. The numbers they give are crank HP numbers, always. They cannot assume any sort of drivetrain loss, they have no clue what car will be using the system, but they have very accurate formulas for calculating power output of a given amount of nitrous and fuel. Use thier experience.
It ran, and I pulled a relatively quick tc that made 330whp on my same dyno that I hit 255 with.
Dunno on the knock thing, but I do know that it runs excessively rich.
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wrong. I've done a 90 shot on a 2.9" pulley and it held up just fine, you just have to tune for it. The 75 shot on JUST stage 2 is fine, no stage 2 with a smaller pulley or any of that ****, or you WILL take out a piston. I've seen it happen to two cars personally. If you tune for it, you can do it just fine. My recommendations?
If you are stage 2+ , stay with a 50 shot. Traction will be more of a problem than power if you've done your modding correctly. 3rd gear wheelspin on street tires for me.
If you are true stage 2, meaning 3.07" pulley and GM tune with 20+ degrees of timing, you can run a 75 shot at max, but it is pushing it. My advice is get a tune if you run more than a 50 shot.
If you are stock pulley/tune, you can easily get away with a 75 shot untuned, or 100+ tuned (stock timing numbers can be in the 28deg range, way too high for nitrous).
I've done up to a 90 shot on stock bottom end with no problems whatsoever as long as it was tuned to be safe. A 75 shot on stock internals with stage 2 timing maps and a smaller pulley WILL break something, i've done it, as have others locally and on here. Be careful.
Final thought, be SURE of your shot, find someone who has some knowledge and ask them about jets, or call the company that makes your kit, they can tell you exactly what the jets are rated at. The numbers they give are crank HP numbers, always. They cannot assume any sort of drivetrain loss, they have no clue what car will be using the system, but they have very accurate formulas for calculating power output of a given amount of nitrous and fuel. Use thier experience.
If you are stage 2+ , stay with a 50 shot. Traction will be more of a problem than power if you've done your modding correctly. 3rd gear wheelspin on street tires for me.
If you are true stage 2, meaning 3.07" pulley and GM tune with 20+ degrees of timing, you can run a 75 shot at max, but it is pushing it. My advice is get a tune if you run more than a 50 shot.
If you are stock pulley/tune, you can easily get away with a 75 shot untuned, or 100+ tuned (stock timing numbers can be in the 28deg range, way too high for nitrous).
I've done up to a 90 shot on stock bottom end with no problems whatsoever as long as it was tuned to be safe. A 75 shot on stock internals with stage 2 timing maps and a smaller pulley WILL break something, i've done it, as have others locally and on here. Be careful.
Final thought, be SURE of your shot, find someone who has some knowledge and ask them about jets, or call the company that makes your kit, they can tell you exactly what the jets are rated at. The numbers they give are crank HP numbers, always. They cannot assume any sort of drivetrain loss, they have no clue what car will be using the system, but they have very accurate formulas for calculating power output of a given amount of nitrous and fuel. Use thier experience.
Now my question. I have this (the bolded section of your writing). Reason I didn't bold the stage 2 timing maps is because my buddy has lowered my timing on his HPTuners.. but my questions are...
-Do you know how exactly to go about changing the timing map from the stage 2 tune in order for it to run right on the 75 shot?
-If done right.. With lower timing than the stage 2 timing... The 75 shot on stock internals with a 2.9 pulley will be fine?
-What would be your recommendation to do first in my situation?
1) Try a bigger fuel jet (possibly even rich to start off)
2) Purchase 60s.. (Although I don't see the need since I run fine with no knock on stage 2 with 2.9 when I'm not on the juice)
Good stuff Joe.
Now my question. I have this (the bolded section of your writing). Reason I didn't bold the stage 2 timing maps is because my buddy has lowered my timing on his HPTuners.. but my questions are...
-Do you know how exactly to go about changing the timing map from the stage 2 tune in order for it to run right on the 75 shot?
-If done right.. With lower timing than the stage 2 timing... The 75 shot on stock internals with a 2.9 pulley will be fine?
-What would be your recommendation to do first in my situation?
1) Try a bigger fuel jet (possibly even rich to start off)
2) Purchase 60s.. (Although I don't see the need since I run fine with no knock on stage 2 with 2.9 when I'm not on the juice)
Now my question. I have this (the bolded section of your writing). Reason I didn't bold the stage 2 timing maps is because my buddy has lowered my timing on his HPTuners.. but my questions are...
-Do you know how exactly to go about changing the timing map from the stage 2 tune in order for it to run right on the 75 shot?
-If done right.. With lower timing than the stage 2 timing... The 75 shot on stock internals with a 2.9 pulley will be fine?
-What would be your recommendation to do first in my situation?
1) Try a bigger fuel jet (possibly even rich to start off)
2) Purchase 60s.. (Although I don't see the need since I run fine with no knock on stage 2 with 2.9 when I'm not on the juice)
Also, regarding A/F, you want to be a touch richer on bottle than off, but your only way of fuel tuning for bottle is through jetting. Setup your tune with a good A/F on motor (say 11.8:1 for arguments sake), then when you spray, you want to be at a steady, lower A/F (say 11.2:1 or so). Adjust your jet sizing until you get tthere. Because the nitrous jet is a larger jet, small changes of 1-2 points are less dramatic, so sometimes if it's running just a tad lean, it's better to go two points smaller on the nitous side than 2 bigger on fuel. That's about a 10hp loss though if you drop the nitrous jet down, so keep that in mind.
I would play with jetting, I ran my car and all the other nitrous cars I setup on 42lb injectors. As you aren't using the injectors to add fuel for the nitrous, 60's won't help you.
wrong. I've done a 90 shot on a 2.9" pulley and it held up just fine, you just have to tune for it. The 75 shot on JUST stage 2 is fine, no stage 2 with a smaller pulley or any of that ****, or you WILL take out a piston. I've seen it happen to two cars personally. If you tune for it, you can do it just fine. My recommendations?
If you are stage 2+ , stay with a 50 shot. Traction will be more of a problem than power if you've done your modding correctly. 3rd gear wheelspin on street tires for me.
If you are true stage 2, meaning 3.07" pulley and GM tune with 20+ degrees of timing, you can run a 75 shot at max, but it is pushing it. My advice is get a tune if you run more than a 50 shot.
If you are stock pulley/tune, you can easily get away with a 75 shot untuned, or 100+ tuned (stock timing numbers can be in the 28deg range, way too high for nitrous).
I've done up to a 90 shot on stock bottom end with no problems whatsoever as long as it was tuned to be safe. A 75 shot on stock internals with stage 2 timing maps and a smaller pulley WILL break something, i've done it, as have others locally and on here. Be careful.
Final thought, be SURE of your shot, find someone who has some knowledge and ask them about jets, or call the company that makes your kit, they can tell you exactly what the jets are rated at. The numbers they give are crank HP numbers, always. They cannot assume any sort of drivetrain loss, they have no clue what car will be using the system, but they have very accurate formulas for calculating power output of a given amount of nitrous and fuel. Use thier experience.
If you are stage 2+ , stay with a 50 shot. Traction will be more of a problem than power if you've done your modding correctly. 3rd gear wheelspin on street tires for me.
If you are true stage 2, meaning 3.07" pulley and GM tune with 20+ degrees of timing, you can run a 75 shot at max, but it is pushing it. My advice is get a tune if you run more than a 50 shot.
If you are stock pulley/tune, you can easily get away with a 75 shot untuned, or 100+ tuned (stock timing numbers can be in the 28deg range, way too high for nitrous).
I've done up to a 90 shot on stock bottom end with no problems whatsoever as long as it was tuned to be safe. A 75 shot on stock internals with stage 2 timing maps and a smaller pulley WILL break something, i've done it, as have others locally and on here. Be careful.
Final thought, be SURE of your shot, find someone who has some knowledge and ask them about jets, or call the company that makes your kit, they can tell you exactly what the jets are rated at. The numbers they give are crank HP numbers, always. They cannot assume any sort of drivetrain loss, they have no clue what car will be using the system, but they have very accurate formulas for calculating power output of a given amount of nitrous and fuel. Use thier experience.
Thread Starter
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lol Ethan bro I'm just trying to get help. Don't be pissed because I don't want to buy your wideband.. If you can help me.. Then help.. If not.. You're not helping anyone by being negative and basically telling me I'm gonna blow my **** up.
And everyones told you get better fuel jets...!!!
Last edited by SlowBalt_06; Sep 2, 2009 at 08:51 PM. Reason: Automerged Doublepost
Damien, HPT doesn't have any sort of map switching, so you'd be forced to run your nitrous tune at all times to be ready to spray (would work at the track, not so much on the street), so i'd advise against it. In general, if you are planning on running nitrous and pulling timing anyway, you might as well get the AFR dialed in to make the best power you can, as you will be down in power with less than ideal timing when off bottle. On bottle, you can jet to add fuel to keep the AFR safe.
You DO need a wideband to make simple changes feasible.
Joe, I meant building a tune strictly for spray, and building a completely different tune for no spray. Then flashing the car when one or the other is needed. If I knew I had a race coming worthy of using the juice, i'd take a few minutes and flash the car.
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It sucks bad that there's no map switches available on HPT!
BOOOOO.
lol. I think I will just drive around on my nitrous tune anyway.. No point in racing w/out nitrous once you have it... That's like running your marathon with both legs tied up when you can simply untie them and run like a champ
BOOOOO.
lol. I think I will just drive around on my nitrous tune anyway.. No point in racing w/out nitrous once you have it... That's like running your marathon with both legs tied up when you can simply untie them and run like a champ
and seeing as you're looking at doing it the cheap way and not the right way.. he could be right
remember pick 2
cheap
fast
reliable