1/4 mile times need improvement: help!
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1/4 mile times need improvement: help!
Last week I went to the track for the first time. After installing 3.42's, a small converter and shift kit, cam, intake, full exhaust, and 100 shot of nitrous, i was expecting 13's. To my dismay, i only ran high 14's. Mind you, it was my first time at the track and i really didn't know what i was doing, but still... Anyways, i was wondering what advice you guys would have for me (ie. tire pressure in street tires, etc) and any other tips. thanks million.
r/t: .722
60' : 2.213
330: 6.271
1/8: 9.608
mph: 74. 17
1000: 12.434
1/4: 14.811
mph: 94.61
r/t: .722
60' : 2.213
330: 6.271
1/8: 9.608
mph: 74. 17
1000: 12.434
1/4: 14.811
mph: 94.61
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
What are the specs on that cam and what intake are you using? Give us some more info on it, also, did you get a posi carrier with those 3.42's? You may need to do some suspension mods to lower those 60' times. Check out some aftermarket LCA's and maybe look into some subframe connectors.
#3
Drop the 60 .2 and ull see mid 14s, that is kinda slow tho im guessing u gotta LT1 cam since u didnt change heads, my boy with a SS impalla ran a 15 flat, and I beat him with my maro when I only had full exaust and 3.73s, barely tho so im guessing I ran a 14.9 with a stock L03 and gears and exaust, you should definetly see 13s tho with a 100 shot, drop the 60 a lil, when are you pushing the button?
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The cam is a crane cams compu cam w/ 208/214 @ .438/.452. I'm running an edelbrock performer rpm intake. The gears do have a new posi unit with them. The suspension is all stock which may be one of my biggest problems. I haven't done much w/ the ignintion- just ran the colder plugs, 8 mm moroso wires and a new cap and rotor. Let me know what you guys think. thanks
donnie
donnie
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
Are u running on the stock tune/injectors/fuel pump. You may be starving for fuel would be my geuss. Also if you are running on the stock tune that is you problem right there.
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I am on the stock tune per say, but i took out my fuel pressure regulator and made it adjustable. I have it set at around 14.5 right now? Should i try and jack it up some more or do i need to go the full route and get a new intank pump?
#9
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Ever consider he might actually be running rich? If you have a NOS system, which you never answered which one you are using for some reason, on the stock jetting, you are probably running rich, not lean. NOS likes to be VERY conservative on their jetting from the factory for obvious reason. Most people gain a lot just from jetting down the fuel, but just make sure you take it in little steps and don't go too far or you could go lean and cause detonation and say bye bye to that engine.
#10
r/t: .722
I don't wish to be too critical, I know you said it was your first time out, but you can easily shave 1/2 sec. right here. You said you got a small converter. What stall speed? Were you reving to near stall speed when you launched? If not, that will add serious time to your reaction time. Also, you should datalog a few runs to see what is really going on. Just my .02
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No prob, i need all the criticism i can get at this point. I just had the trans rebuilt and a transgo shift kit and "corvette" converter installed. the guy told me it should stall around 2400-2600, but its breaking loose at less than two grand. I went back out last night and made a couple of passes not using the nitrous. My times were almost as good and i've got my r/t's down pat. I just need to get some traction when i spray and get my 60 ft times down.
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
You can't shave any time off by getting r/t's down. Your reaction time has nothing to do with your ET you could have a 4 minute reaction time and still run a 13 flat if you had the car to do it. You probably need those suspension mods the most to keep all that nitrous-driven power to the ground. When do you kick in the nitrous exactly?
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Car: '84 Z28
Engine: Goodwrench 350
Transmission: 700R4
Axle/Gears: good guess
Reaction time has nothing to do w/ your 1/4 time. It does'nt start timing you until you break the beams.
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i understand that, i was just stating i got my times down. where i need help its my sixty foot, but i just don't have the cash to be shelling out for slicks right now. thanks for the input though
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
Try boxing your stock LCA's it may give you a little improvement. You still didn't state where you kick the nitrous in either??
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Car: 93 Caprice 9C1
Engine: L05
Transmission: 4L60
Axle/Gears: 3.42
Is it a dry or wet kit? If it's dry, you are going to need WAAAAAY more than 14.5psi. You'll need more the 2x that. Maybe 3x that, if you want to still use the stock injectors. Upsize the injectors and you can go more conservative on the fuel pressure. And this applies only if it's a dry system. If it's a wet system (and I think most TBI nitrous systems are), then the suggestions regarding your AFR are correct. You could be way too rich, or too lean - either way, maybe get a wide band O2 in there to check. You don't want to mess around with nitrous. A little money and time invested now will save a lot of time and money later...
#19
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Originally posted by kevm14
Is it a dry or wet kit? If it's dry, you are going to need WAAAAAY more than 14.5psi. You'll need more the 2x that. Maybe 3x that, if you want to still use the stock injectors. Upsize the injectors and you can go more conservative on the fuel pressure. And this applies only if it's a dry system. If it's a wet system (and I think most TBI nitrous systems are), then the suggestions regarding your AFR are correct. You could be way too rich, or too lean - either way, maybe get a wide band O2 in there to check. You don't want to mess around with nitrous. A little money and time invested now will save a lot of time and money later...
Is it a dry or wet kit? If it's dry, you are going to need WAAAAAY more than 14.5psi. You'll need more the 2x that. Maybe 3x that, if you want to still use the stock injectors. Upsize the injectors and you can go more conservative on the fuel pressure. And this applies only if it's a dry system. If it's a wet system (and I think most TBI nitrous systems are), then the suggestions regarding your AFR are correct. You could be way too rich, or too lean - either way, maybe get a wide band O2 in there to check. You don't want to mess around with nitrous. A little money and time invested now will save a lot of time and money later...
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before he starts worrying about how fast it is on the nitrous, shouldn't he get it hooking up and running well without it first?
i'd recommend spending a hundred bucks on a dyno tune with a wideband 02 sensor ... getting the air fuel ratio right before he sprays is critical.
then i'd do something about those 60' times. even when he gets them right, though, i don't think he's going to be able to shoot the juice from the line. he said something to that effect in his posts. a few posts ago, he said it was almost as fast without the nitrous than it was with it. i'm wondering if it's because he shot the nitrous from the start and went up in smoke?
now i've never run nitrous with an efi, but when i used it with a carb, going to a colder plug, backing off on the timing and using a fuel pressure regulator set at 7psi was worth an additional 6 tenths over the disappointing 5 tenths i additionally got with it.
the tech guys at nos said i was actually dumping in too much additional fuel when i shot without the fuel pressure regulator. obviously, the nitrous causes the mixture to go lean, but too much additional fuel kills power.
to get the most out of a nitous shot, you need a separate fuel pressure regulator for the additional fuel you dump in when you et the shot of nitrous.
i'm sure the tech people at the manufacturer can help him with that.
i'd recommend spending a hundred bucks on a dyno tune with a wideband 02 sensor ... getting the air fuel ratio right before he sprays is critical.
then i'd do something about those 60' times. even when he gets them right, though, i don't think he's going to be able to shoot the juice from the line. he said something to that effect in his posts. a few posts ago, he said it was almost as fast without the nitrous than it was with it. i'm wondering if it's because he shot the nitrous from the start and went up in smoke?
now i've never run nitrous with an efi, but when i used it with a carb, going to a colder plug, backing off on the timing and using a fuel pressure regulator set at 7psi was worth an additional 6 tenths over the disappointing 5 tenths i additionally got with it.
the tech guys at nos said i was actually dumping in too much additional fuel when i shot without the fuel pressure regulator. obviously, the nitrous causes the mixture to go lean, but too much additional fuel kills power.
to get the most out of a nitous shot, you need a separate fuel pressure regulator for the additional fuel you dump in when you et the shot of nitrous.
i'm sure the tech people at the manufacturer can help him with that.
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the kit i'm running on the car is in fact a wet system. I've been spraying off the line; the other guys w/ similar set ups said thats the only way to do it. next time out i may wait till second gear and go from there, but i still need to get my act together. thanks for the help.
donnie
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For the hell of it, where are you shifting?
My car is ALOT faster when I shift at 4500 than if I run it to 5500.
I know a kid with a stock L98 that cut a good 60', but managed to run a mid 17. He was running the car to 6500 when he would shift.
My car is ALOT faster when I shift at 4500 than if I run it to 5500.
I know a kid with a stock L98 that cut a good 60', but managed to run a mid 17. He was running the car to 6500 when he would shift.
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