1985 stock injectors
Team Owner
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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No the 85's injectors are rated 24lb at a lower pressure of like 35psi, not 30lb. It is stated in the OP's linked post and has been verified here many times. In 86 they dropped to 22lb/hr rated at a higher pressure of about 45psi, so they end up flowing about the same rates in practice, but the computer is adjusting them a bit differently (different computers between 85-86). The 85's injectors running at the higher pressure will flow more than what 86 has however.
It is not like you need that fuel because the TPI chokes the hell out of the motor.
And Yariv, no you have not done enough to warrant messing with the fuel pressure yet. Spend your money elsewhere for now.
It is not like you need that fuel because the TPI chokes the hell out of the motor.
And Yariv, no you have not done enough to warrant messing with the fuel pressure yet. Spend your money elsewhere for now.
Last edited by vader86; Aug 3, 2016 at 09:08 AM.
Team Owner
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From: Hartford WI
because at WOT the ECM has pre determined settings (according to whoever tuned it)
I know the changes I referred to make a difference between street and track, because I make those changes in my car all the time.
I know that my car will go faster up a hill at 50 psi, why, because it does, if I set my pressure lower the car will be slower and thats a fact !
I know the changes I referred to make a difference between street and track, because I make those changes in my car all the time.
I know that my car will go faster up a hill at 50 psi, why, because it does, if I set my pressure lower the car will be slower and thats a fact !
That is at WOT but what happens when you are going downhill at a relaxed pace or even in the city driving mode where it isn't WOT? Assuming the ECM can adjust, maybe it won't be so bad. OTOH, if it falls outside the adjustment window, you run rich. Maybe it is better to adjust the EPROM to advance timing or change pulse width instead of trying to fool the program.
Team Owner
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From: Hartford WI
But wouldn't it be better to stop screwing with the fuel pressure and just make the changes in the chip so it works throughout the band instead of band aiding the thing?
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Hi There !
The way I like to do it is sell you the following:
> Cable to data log with using TunerPro RT.
> An Ostrich from Moates so we can exchange BIN files after examining your logs.
> After any number of iterations you may then be ready for the dyno if desired.
> Also prefer to sell you a new MAF - slot style matched to your power.
All of this can be quite expensive but in the end well worth it if you cannot do for yourself.
BTW the guy that tunes my L98 MAF cars is Tequila Boy who runs an '87 and is quite the expert !!!!!!!
The way I like to do it is sell you the following:
> Cable to data log with using TunerPro RT.
> An Ostrich from Moates so we can exchange BIN files after examining your logs.
> After any number of iterations you may then be ready for the dyno if desired.
> Also prefer to sell you a new MAF - slot style matched to your power.
All of this can be quite expensive but in the end well worth it if you cannot do for yourself.
BTW the guy that tunes my L98 MAF cars is Tequila Boy who runs an '87 and is quite the expert !!!!!!!
Team Owner
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From: Hartford WI
http://www.hitechmotorsport.com/tuni...category_id=76
Thread Starter
Racer
Joined: Sep 2015
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From: Israel
If you don't have a dyno facility that can tune it for you, a datalog tune would be your next best option. Below that, get someone to tune based on your mods.
http://www.hitechmotorsport.com/tuni...category_id=76
http://www.hitechmotorsport.com/tuni...category_id=76
Team Owner
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From: Athens AL
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I would hold off on that until some other things were done, or if he was totally finished with mods, or got a good deal on tuning cost.
Team Owner
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From: Hartford WI
I see OBX headers, exhaust, and TB. That tells me he hasn't really done enough airflow modifications to justify the expense of a customized tune.
I would hold off on that until some other things were done, or if he was totally finished with mods, or got a good deal on tuning cost.
I would hold off on that until some other things were done, or if he was totally finished with mods, or got a good deal on tuning cost.
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Thread Starter
Racer
Joined: Sep 2015
Posts: 261
Likes: 24
From: Israel
I see OBX headers, exhaust, and TB. That tells me he hasn't really done enough airflow modifications to justify the expense of a customized tune.
I would hold off on that until some other things were done, or if he was totally finished with mods, or got a good deal on tuning cost.
I would hold off on that until some other things were done, or if he was totally finished with mods, or got a good deal on tuning cost.
If the ECM tuning/get a new chip can be done, I'll go for the OBX.
Regarding the MAF and air box, I read an old post of Vader86 explains there is no need for adjustable MAF.
Last edited by Yariv; Aug 3, 2016 at 11:26 AM.
Team Owner
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From: Athens AL
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Don't bother with the adjustable MAFs, waste of money. Airbox is fine.
You really need to think out what you want to do with the intake setup before going the route with ECM tuning. You won't get the bang for the buck. Let it inhale, then you can start playing with pressure regulators and ECM tuning on a dyno.
You really need to think out what you want to do with the intake setup before going the route with ECM tuning. You won't get the bang for the buck. Let it inhale, then you can start playing with pressure regulators and ECM tuning on a dyno.
Team Owner
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From: Hartford WI
I sent an email to http://hitechmotorsport.com/. Wait for their reply to understands my ECM options.
If the ECM tuning/get a new chip can be done, I'll go for the OBX.
Regarding the MAF and air box, I read an old post of Vader86 explains there is no need for adjustable MAF.
If the ECM tuning/get a new chip can be done, I'll go for the OBX.
Regarding the MAF and air box, I read an old post of Vader86 explains there is no need for adjustable MAF.
Thread Starter
Racer
Joined: Sep 2015
Posts: 261
Likes: 24
From: Israel
Hi,
Here is an answer from Brat: "Tuning with your mods is not worth the cost. Headers and exhaust will not change it that much either. The best mod for your car is a gear change to 3.73/3.90/4.11."
So, your answers point me to leave the Vette as is.
Thank you all.
Here is an answer from Brat: "Tuning with your mods is not worth the cost. Headers and exhaust will not change it that much either. The best mod for your car is a gear change to 3.73/3.90/4.11."
So, your answers point me to leave the Vette as is.
Thank you all.
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From: Hartford WI
To be honest, the only time I felt a difference in my F-body is when I did intakes and headers but I am not sure how different the F-body programming is from Y-body. That was done by Lingenfelter when he was alive.
Team Owner
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From: Hartford WI
I don't know if my F-body was that different but I went from a 3.73 to a 4.10. A little more pickup but gas mileage sucked. For my combination, they told me to go with a 3.54 gear but I knew better. I also got to know the gas station people better too. I should have piched that rear end for a Ford 10 inch or a Chevy 12 bolt instead of trying to make the 7.625 rear end work. Spun the bearings, broke gears but I knew better.
I should have piched that rear end for a Ford 10 inch or a Chevy 12 bolt instead of trying to make the 7.625 rear end work. Spun the bearings, broke gears but I knew better.