Still No Midrange Power

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Jul 23, 2011 | 01:30 PM

Krazymaan

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Still No Midrange Power

The only way my van accelerates is from the transmission shifting into another gear when cold. So last weekend i did the in tank mod, drilled out the fuel plugs to 1/4 inch, checked this checked that again. I finally got my electronic fuel pressure gauge. I hooked it up this morning to the fuel rail behind #8 and to my surprise I have 69-72psi's Thats awesome but doesn't make my van run any better. So according to me, I must have bad injectors.
Luckily for me I have stage 1's sitting there waiting for PHP to reburn my tsperformance chip and send back to me. Now that I eliminated everything but the injectors it must be them.

Jul 23, 2011 | 01:43 PM

HD Rider

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Joined: Aug 2009

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From: Glendive, MT

It almost sounds like you need to do some data loging with AE or similar.

Jul 23, 2011 | 02:24 PM

timmyboy76

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Quote:

Originally Posted by Krazymaan

So last weekend i did the in tank mod, drilled out the fuel plugs to 1/4 inch, checked this checked that again.

thought about doing that, (1/4in fuel plug) is there any gain from it?

Jul 23, 2011 | 07:19 PM

Krazymaan

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Quote:

Originally Posted by timmyboy76

thought about doing that, (1/4in fuel plug) is there any gain from it?

The technical answer is NO. But the other answer is Yes. You see, you have four 1/8" holes with a circumference of .79 allowing fuel to enter the head per fuel plug. which add up to a circumference of 3.16 But the 1/4" hole in the center is only has a circumference of 1.57 Important fact to remember is that two 1/8" holes does not flow the same amount as one 1/4" hole. A 1/4" hole still flows more. Thats why you have to add up the circumferences (outside diameter). So from factory you already have a double capacity inlet, four 1/8"'s and only one outlet at 1/4". But by drilling one set of those 1/8" holes bigger (the one by the threads) you increase the inflow to a circumference of 4.72 even though the outlet of 1/4" is still 1.57. So the technical answer is No, there will be absolutely no improvement. But the other answer is Yes because if you add a stronger fuel pump you can force more fuel at a faster rate through the hole when your engine demands it. Wow, I actually wrote something technical