guys please help...correct answer will get 50 bucks paypaled to them
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From: Wichita Falls, TX
The jetting for a 150shot at 45 psi. is 62n 35f. If your air fuel was fine on the dyno during testing, you may have an ignition problem. easy way to tell is lower your HP to a 100 or 75 shot if the car hauls the mail, and back fires on the larger setting (air fuel being ok) its in the ignition.
The reason is, you are under a greater load when not on the dyno. This make the ignition work harder.
another way is to move your start window to a higher point, say 4000.
There is a point where you are trying to shove so much nitrous into the engine, and it only needs to bog for a breif moment in time to cuase a backfire.
Things to look at anyway.. Call us and talk direct.
Ricky
The reason is, you are under a greater load when not on the dyno. This make the ignition work harder.
another way is to move your start window to a higher point, say 4000.
There is a point where you are trying to shove so much nitrous into the engine, and it only needs to bog for a breif moment in time to cuase a backfire.
Things to look at anyway.. Call us and talk direct.
Ricky
Like Ricky Said...moving your start rpm up may be necessary. That 3500 rpm for the on point sounds ok. But its still a 3.0 motor. You have to take that into account. For arguement sake that would be like spraying a 6.0 LS2 at 1750 rpm (assuming VE was similair).
Best thing to do would for that high reving 3.0 inline motor to go with a dual stage. 75 shot at 3500 and another 75 shot at 4600 or so. Of course this is assuming everything is working as it should and your Af is correct.
That smaller displacement high reving 3.0 inline will benifit GREATLY from a dual stage as far as power and safety.
Best thing to do would for that high reving 3.0 inline motor to go with a dual stage. 75 shot at 3500 and another 75 shot at 4600 or so. Of course this is assuming everything is working as it should and your Af is correct.
That smaller displacement high reving 3.0 inline will benifit GREATLY from a dual stage as far as power and safety.
Okay here is what im going to do
1. Put new plugs in- 2 steps colder.
2. Since car worked fine on 75 shot, Im going to try 100, and if that works, then 125.
3. If 125 works I will try 150 once more again, if it backfires again, time to go to dyno for wideband tuning and better fuel puressure monitoring so I can figure what's going on here to find out if its either a lack of fuel puressore or ignition.
Hopefully the new plugs fix this!
Come to think of it, the first time i used the 150 on the street the plugs were puddled with fuel because my nitrous bottle was mounted backwards so it was dumping all this fuel into the engine and no nitrous, causing my intake filter to start on fire. Maybe it did something to the plugs which I am experiancing now.
1. Put new plugs in- 2 steps colder.
2. Since car worked fine on 75 shot, Im going to try 100, and if that works, then 125.
3. If 125 works I will try 150 once more again, if it backfires again, time to go to dyno for wideband tuning and better fuel puressure monitoring so I can figure what's going on here to find out if its either a lack of fuel puressore or ignition.
Hopefully the new plugs fix this!
Come to think of it, the first time i used the 150 on the street the plugs were puddled with fuel because my nitrous bottle was mounted backwards so it was dumping all this fuel into the engine and no nitrous, causing my intake filter to start on fire. Maybe it did something to the plugs which I am experiancing now.
Originally Posted by ToyotaSupra
Okay here is what im going to do
1. Put new plugs in- 2 steps colder.
2. Since car worked fine on 75 shot, Im going to try 100, and if that works, then 125.
3. If 125 works I will try 150 once more again, if it backfires again, time to go to dyno for wideband tuning and better fuel puressure monitoring so I can figure what's going on here to find out if its either a lack of fuel puressore or ignition.
Hopefully the new plugs fix this!
Come to think of it, the first time i used the 150 on the street the plugs were puddled with fuel because my nitrous bottle was mounted backwards so it was dumping all this fuel into the engine and no nitrous, causing my intake filter to start on fire. Maybe it did something to the plugs which I am experiancing now.
1. Put new plugs in- 2 steps colder.
2. Since car worked fine on 75 shot, Im going to try 100, and if that works, then 125.
3. If 125 works I will try 150 once more again, if it backfires again, time to go to dyno for wideband tuning and better fuel puressure monitoring so I can figure what's going on here to find out if its either a lack of fuel puressore or ignition.
Hopefully the new plugs fix this!
Come to think of it, the first time i used the 150 on the street the plugs were puddled with fuel because my nitrous bottle was mounted backwards so it was dumping all this fuel into the engine and no nitrous, causing my intake filter to start on fire. Maybe it did something to the plugs which I am experiancing now.
get the car on a load bearing dyno and see where the a/f is at.
Originally Posted by NXRICKY
The jetting for a 150shot at 45 psi. is 62n 35f. If your air fuel was fine on the dyno during testing, you may have an ignition problem. easy way to tell is lower your HP to a 100 or 75 shot if the car hauls the mail, and back fires on the larger setting (air fuel being ok) its in the ignition.
The reason is, you are under a greater load when not on the dyno. This make the ignition work harder.
another way is to move your start window to a higher point, say 4000.
There is a point where you are trying to shove so much nitrous into the engine, and it only needs to bog for a breif moment in time to cuase a backfire.
Things to look at anyway.. Call us and talk direct.
Ricky
The reason is, you are under a greater load when not on the dyno. This make the ignition work harder.
another way is to move your start window to a higher point, say 4000.
There is a point where you are trying to shove so much nitrous into the engine, and it only needs to bog for a breif moment in time to cuase a backfire.
Things to look at anyway.. Call us and talk direct.
Ricky
upgrade your pump it wont support a 150 shot ur running out of fuel. paypal is lookout21@optonline.net 
Originally Posted by n2oJOE
upgrade your pump it wont support a 150 shot ur running out of fuel. paypal is lookout21@optonline.net
Then how is it my car worked perfectly on 150 shot on the dyno???????
no load
u need to log your fuel pressure and a/f but i think thats what your gonna find the n/a pump wont support that much fp, if it was a tt pump u would be ok. thats what it sounds like to me. try and spray a 100 or 125 and see what happens. it sounds like you found the limit of your stock pump at 150.
u need to log your fuel pressure and a/f but i think thats what your gonna find the n/a pump wont support that much fp, if it was a tt pump u would be ok. thats what it sounds like to me. try and spray a 100 or 125 and see what happens. it sounds like you found the limit of your stock pump at 150.
Originally Posted by n2oJOE
no load
u need to log your fuel pressure and a/f but i think thats what your gonna find the n/a pump wont support that much fp, if it was a tt pump u would be ok. thats what it sounds like to me. try and spray a 100 or 125 and see what happens. it sounds like you found the limit of your stock pump at 150.
u need to log your fuel pressure and a/f but i think thats what your gonna find the n/a pump wont support that much fp, if it was a tt pump u would be ok. thats what it sounds like to me. try and spray a 100 or 125 and see what happens. it sounds like you found the limit of your stock pump at 150.
yeah I agree with this. It's the only thing making sense.
Im going to try 100 and then if that works 125 and watch my fuel pressure. I will then try 150 and watch the fuel pressure if everything was okay previously to see if it is in fact my fuel pump. If it is, the stock TT pumps are cheap and i can probably find one for 30 shipped or something
I'll let you know! if you're right, i'll be sending the 50 ur way!
I read through the replies and there are some good ideas, escpecially, making sure you keep sufficient fuel pressure.
Also look at your intake valve and springs. (especially since you already had a backfire)
If the springs are soft or if an intake valve isn't seated properly, it will create a backfire even if the car is tuned properly.
Look on the bright side, at least you have an aluminum intake manifold, unlike these plastic manifolds like an LS motor.
Vinny
Also look at your intake valve and springs. (especially since you already had a backfire)
If the springs are soft or if an intake valve isn't seated properly, it will create a backfire even if the car is tuned properly.
Look on the bright side, at least you have an aluminum intake manifold, unlike these plastic manifolds like an LS motor.
Vinny
Last edited by 860 Performance; Mar 5, 2007 at 05:19 PM.
In my mind, which is a cyclone of random boob shots and missed second to third shifts, you should check out the fuel pressure like everyone is saying and if there is an inkling of doubt, ****** up a good fuel pump and skip right past the stocker. Never hurts to have a good fuel pump with a power adder, just good peace of mind methinks.
Originally Posted by Robert56@NitrousDirect
Remember, you'll need the proper jetting for the 75 hit also at your 45psi. Even though the 75 shot seemed fine, it can be running lean also, just not high enough clyinder pressures compared to the 150 to cause problems. I am not a supra guy so I can not tell ya how much hp the fuel pump can supply, but your jetting of 65/35 and the rec 62/38 from ricky verified that you had it jetted lean.
75hp-41/24
100hp-52/33
150hp-62/38
This is why we allways rec dyno tune or logging parameters. A WB is the best tool a nitrous guy can have. Logging a/f will tell ya if you have your jetting correct, and if you seem to be going lean at higher rpms/demand area, then fuel pump is likely not keeping up. Dropping fuel pressure at highest demand is another way to see fuel pump giving out. Keep us updated. Trying to diagnostics over the internet is a little hard at best. Some very good minds have given very good insight for you to use, a great bunch of tech heads, good luck.
Robert
Robert
75hp-41/24
100hp-52/33
150hp-62/38
This is why we allways rec dyno tune or logging parameters. A WB is the best tool a nitrous guy can have. Logging a/f will tell ya if you have your jetting correct, and if you seem to be going lean at higher rpms/demand area, then fuel pump is likely not keeping up. Dropping fuel pressure at highest demand is another way to see fuel pump giving out. Keep us updated. Trying to diagnostics over the internet is a little hard at best. Some very good minds have given very good insight for you to use, a great bunch of tech heads, good luck.
Robert
Robert
I ran .062 N and .038 Fuel so i was being on the rich side of things...
and after talking with NX today with 45psi it goes as followed:
100 shot 52 N and 31 F
125 shot 57 N and 33 F
150 shot 62 N and 35 F
Originally Posted by ToyotaSupra
Those jet #'s are wrong. I never ran a 35 Fuel on my 150 shot
I ran .062 N and .038 Fuel so i was being on the rich side of things...
and after talking with NX today with 45psi it goes as followed:
100 shot 52 N and 31 F
125 shot 57 N and 33 F
150 shot 62 N and 35 F
I ran .062 N and .038 Fuel so i was being on the rich side of things...
and after talking with NX today with 45psi it goes as followed:
100 shot 52 N and 31 F
125 shot 57 N and 33 F
150 shot 62 N and 35 F
Robert