He does not use a aftermarket fpr probably cause he charges more to tune then he does to install a fpr.
An aftermarket FPR does not mean you avoid having to tune, at least as regards a FI build.
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He does not use a aftermarket fpr probably cause he charges more to tune then he does to install a fpr.
Wow. Just came back to this one...
The fuel pressure creep can also be addressed in the tuning...for those that can do it.
With our SCT our tuning, we can stop the computer from learning idle fuel trims and f'n up the program.
Both the white car and the green car are '91's with a 255lph in the tank and stock FPR's(and now the blue 95 ATX - Next is the white V-8 car - stay tuned). Proper tuning, no issues.
This is the sh^t I was trying to find out in previous posts, about how is it possible that this car has just injectors and fpr and everything is fine and so many threads here, about how you nhave to use FPR with big injectors on boosted cars and here is a turbo kit without FPR.This sounds like something that would come from the Vadim playbook. Sure, you can disable the computers ability to learn any fuel trims, but that's a half-assed way to do it. Once you start driving through drastically different atmospheric conditions, what are you relying on for any type of compensation?
This is NOT what I would call "proper tuning". This type of tuning is not something I would pay someone for; are you informing your customers exactly what you're doing?
For anyone reading this and looking to boost/put in a >155lph pump and big injectors, just spend the $200(ish) and get an adjustable FPR from Josh. You could make your own setup for a little less, but it's nice to buy something already sized for the car.
I've seen your previous posts and I highly suggest taking the time to understand how the fuel system works, as well as how the EEC handles fuel.This is the sh^t I was trying to find out in previous posts, about how is it possible that this car has just injectors and fpr and everything is fine and so many threads here, about how you nhave to use FPR with big injectors on boosted cars and here is a turbo kit without FPR.
I'd like to read more arguements on this one, if there are any.
The whole point is that once the car is set properly, it's DONE.
I go back to the Kurt Metros example with his '90 with the blower. He got Jerry (famous tuner at the time) to tune his car. At that time, it was the BEST s/c SHO out there. True turn-key with no issues.
I defend Doug in this. Once the car is set up, it's DONE. Why spend the extra $$$ if it's not needed??
Why spend $$ if it's not required? If I've learned nothing else in 40+ years of modifying cars, it's that staying with stock parts whenever possible is a good thing.
I've seen your previous posts and I highly suggest taking the time to understand how the fuel system works, as well as how the EEC handles fuel.
Basically, he is tuning for a constant and not allowing the pump and FPR to maintain the same pressure differential through vacuum and boost, which will not allow EEC to compensate for any type of changes. In addition, if you were to take this type of tune, then put on a proper FPR and re-enable the EEC's learning ability, you'll quickly go lean under WOT.
As manifold pressure rises, the fuel pressure should rise. This works both ways... When manifold pressure drops, fuel pressure should drop (base pressure is set/referenced at atmospheric pressure). With the stock FPR and a pump that is too large, you do not get this relationship.
I can't really agree that it's "done" or with this technique being referred to as "properly". He's disabling the computer's ability to compensate for any type of changes regarding fuel. Moving from somewhere like Atlanta, to Denver will almost likely require an adjustment in tuning. Even a properly tuned car is constantly swaying back in forth in fuel changes. It is accounting for all the variables, that we can't predict, by comparing input vs output.
I agree with this practice, however, I don't think this is one that should be left stock if running a pump that is too large for the stocker.
Well, if you move from Atlanta to Denver, get a new tune.....
IMO, this is BS. Get the car set....it's set......if you life is that much in flux where you move across the country once a year, do something different.
IMO, Doug's solution works for 99.999% of the people. From what I've seen, there are WAYY too many s/c and turbo folks who never get things right. I have seen what a good tune does on a stable car like Kurt's, and I have seen Doug's cars that also work well.
Success is what matters. After 40+ years of modifying cars, I have learned what a lot of you "may" also learn someday. Before that, you will all keep ******* around with shit that just makes your cars suboptimal.
I defend Doug in this. Once the car is set up, it's DONE. Why spend the extra $$$ if it's not needed??
oh, so now I see. I Doug's setup, there is no way back or forward out of this setup, unless you're tuning it.
On the other hand, i take my car out in winter , sometimes, when road is clear, just for a ride, or I like to go to different places in the mountains and all that, so does this mean that I will have a problem with the tune if I drive from warmer area to colder and vice versa?
And another thing I cannot understand still, is why so much torque and a lot less HP?
More importantly, it runs out of efficiency at higher demand.The high TQ low HP is due to the small sized turbo. A smaller turbo creates more back pressure.
Dumb argument.

If I've learned nothing else in 40+ years of modifying cars, it's that staying with stock parts whenever possible is a good thing.
While I don't agree that a FPR is un-needed, I don't get why there's all this arguing.
Obviously neither side is going to convince the other, what's the point?