Need some help/input on tuning.
Thread Starter
Drifting
Joined: Oct 1999
Posts: 1,722
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From: Gloucester Va
Need some help/input on tuning.
I can finally start tuning my car now. It's a 383 based off of LPE's 383 for L-98. I have had a chip done by Ed wright, and I have done some tuning, but there doesn't seem to be a great deal I can. Timing and fuel pressure seem to be about it. IS this right, or are there other things? I have done a little tuning but the car just does not seem to have the power. Mainly in 3rd. if I get on it in 3rd, but not enough for it to down shift, it goes, but not like I think it should. I still have 2.59 gears, and stock converter. Is it possible these could be causing a major loss in power getting to the wheels?
[Modified by 88_vette, 4:31 PM 9/15/2001]
[Modified by 88_vette, 4:31 PM 9/15/2001]
Race Director
Joined: Mar 2001
Posts: 14,480
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From: PA
Re: Need some help/input on tuning. (88_vette)
Probably the best advice I could give you is find a tuner with a chassis dyno. That's the only way you're going to know for sure if you're tuned right. Like you didn't know that already. 
Thread Starter
Drifting
Joined: Oct 1999
Posts: 1,722
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From: Gloucester Va
Re: Need some help/input on tuning. (Nat96LT4)
Thanks Nat,
I raced a 2001 Roush today. I'm not sure what stage. I pulled away from him for the most part. About 3 cars before we had to slow it down. Which tells me the car is running OK for the most part. I guess I will have to break down and do a dyno tune. After all the money thus far why not dyno tune to get your moneys worth right?
[Modified by 88_vette, 3:33 PM 9/16/2001]
I raced a 2001 Roush today. I'm not sure what stage. I pulled away from him for the most part. About 3 cars before we had to slow it down. Which tells me the car is running OK for the most part. I guess I will have to break down and do a dyno tune. After all the money thus far why not dyno tune to get your moneys worth right?
[Modified by 88_vette, 3:33 PM 9/16/2001]
Melting Slicks
Joined: May 1999
Posts: 2,037
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From: Sarasota FL
Re: Need some help/input on tuning. (88_vette)
Timing and fuel pressure? You obviously haven't looked into chip tuning. Turning the dist and bumping up fuel pressure are really generic/crappy ways to tune a TPI engine. Read the prom burning intro at http://www.thirdgen.org. You can change a whole lot in the PROM to make the car a different animal. Fine tuning by yourself will give you much more power and drivability than any tune over the phone chip. Ask RICH86'ZZ4 how different his car ran after we tuned it - especially since his 'custom' chip was a joke.
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Re: Need some help/input on tuning.
Quote :
Mainly in 3rd. if I get on it in 3rd, but not enough for it to down shift, it goes, but not like I think it should. I still have 2.59 gears, and stock converter. Is it possible these could be causing a major loss in power getting to the wheels?
Yes.
Mainly in 3rd. if I get on it in 3rd, but not enough for it to down shift, it goes, but not like I think it should. I still have 2.59 gears, and stock converter. Is it possible these could be causing a major loss in power getting to the wheels?
Yes.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Need some help/input on tuning. (88_vette)
Of course you have half the RWHP in 3rd as in 1st but there could be other issues
You can use a scan tool and FP gauge to be sure you're not running out of fuel by the time you start to pull in 3rd nor getting knock retards that pull some timing. If FP drops off you may need a larger FP, if knock counts upgrade your ECS module.
You can use a scan tool and FP gauge to be sure you're not running out of fuel by the time you start to pull in 3rd nor getting knock retards that pull some timing. If FP drops off you may need a larger FP, if knock counts upgrade your ECS module.
Thread Starter
Drifting
Joined: Oct 1999
Posts: 1,722
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From: Gloucester Va
Re: Need some help/input on tuning. (65Z01)
Thanks for the tips guys. I agree FP, and timing are crappy ways to tune on these, but seeing as how I can not program the prom myself it's about all i have. I think my chip maybe crap. I really can not feel a difference in power from a TPIS chip I had made when it was a 350 stock, and the 383 chip. This is my 3rd reprogram. It runs about the same with both, which has me wondering. Chip, or something else? I've gone over the car well, and can not find any problems related to motor. I have a sevice manual and have pretty much done every check on every item on the car. I have not found one thing wrong. So, it's hard to think something else besides chip at this point. My setup is a very common one. I have another converter that I got, and never put in. Maybe I will try it. It's a 2600 arttcarr.
Aron 87.
Are you programing chips? I remember you talking about it some time ago. I have done a lot of research into the prom burning, but I have just been really busy over the past 4 months. So, would you say a scan tool and a day at the dyno would be the best way to go in burning my own chip? I have learned enough to start playing with proms, but I do not have the stuff to do it.
Aron 87.
Are you programing chips? I remember you talking about it some time ago. I have done a lot of research into the prom burning, but I have just been really busy over the past 4 months. So, would you say a scan tool and a day at the dyno would be the best way to go in burning my own chip? I have learned enough to start playing with proms, but I do not have the stuff to do it.
Melting Slicks
Joined: May 1999
Posts: 2,037
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From: Sarasota FL
Re: Need some help/input on tuning. (88_vette)
A day at the dyno might be useful, but not necessary. Craig Moates laptop scanner reads the VSS and either interpolates power or 1/4 mile or something. That'll help you decide if you've made a power improvement. So will trap speed at the track, and a test & tune is $10 instead of $100/hour dynos. I use my G Tech a lot also. I don't like using the butt-o-meter, but you can usually feel the changes. Remember, there's more to the equation than WOT tuning.
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From: Hillsboro OR
Re: Need some help/input on tuning. (88_vette)
I'd suggest that you have a dyno run performed to get a baseline for where your at. Make sure they take an Air to Fuel Ratio measurement during the test run. Concentrate on the air to fuel ratio above 3500 RPM because your 383 will consume more air in that RPM range than the ECM can read from the MAF. The air to fuel ratio must be richer in the programming to get around this problem and the tuner needs to understand this to do the chip correctly.
You setup is pretty common. Anyone who has a 383 with the same cam, heads and intake on an 87-89 L98 running correctly will have a chip that is setup for what you need. They should be able to tell you who programmed the chip. I don't know if Ed Wright has the correct info to burn the correct chip. He says he will work with you so I would keep after him once you get the dyno results.
I also suggest you got to 30# injectors if you haven't already to be sure you have enough fuel flow to supply the motor.
You setup is pretty common. Anyone who has a 383 with the same cam, heads and intake on an 87-89 L98 running correctly will have a chip that is setup for what you need. They should be able to tell you who programmed the chip. I don't know if Ed Wright has the correct info to burn the correct chip. He says he will work with you so I would keep after him once you get the dyno results.
I also suggest you got to 30# injectors if you haven't already to be sure you have enough fuel flow to supply the motor.
Thread Starter
Drifting
Joined: Oct 1999
Posts: 1,722
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From: Gloucester Va
Re: Need some help/input on tuning. (AquaMetallic94LT1)
Thanks again guys. I guess it's off to the dyno and get a base line, and see what I'm looking at and how much I far I have to go.
Aqua:
I never thought about fuel pump. I have 24# injectors, and running stock fuel pump. is it a known fact that the stock pump can not handle the 383 demands?
Aqua:
I never thought about fuel pump. I have 24# injectors, and running stock fuel pump. is it a known fact that the stock pump can not handle the 383 demands?
Melting Slicks
Joined: May 1999
Posts: 2,037
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From: Sarasota FL
Re: Need some help/input on tuning. (88_vette)
Two motors built with the exact same parts will want completely different tuning. You can substitute Craig Moates free scanner for Diacom and WinBin (free and plenty of options for the 6E) for Tunercat. That'll save you some money.