Acceleration hesitation

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puzzigully
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Acceleration hesitation

Post by puzzigully » Mon Jun 25, 2018 12:09 am

Hey guys,

have a 1987 B2K corvette and have severe hesitation/breakdown when asking for full power..
  • Doesn't seem to happen when the fuel tank is full
  • Does seem to happen with tank 1/3 full or less
  • I "think" it's more prevalent after turning a corner (not high G cornering), just your normal intersection turn, straighten up, then try to "stick the boot in" and it starts to accelerate then coughs and splutters until I lift off.
It will accelerate all the way to redline if I use less throttle, but far less acceleration.

Really does feel like a fuel-related issue.

Any suggestions most welcome.

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BIGJOHN
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Re: Acceleration hesitation

Post by BIGJOHN » Mon Jun 25, 2018 6:54 am

You really should never go below 1/2 tank of fuel
:beer

puzzigully
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Re: Acceleration hesitation

Post by puzzigully » Mon Jun 25, 2018 6:49 pm

BIGJOHN,

thanks for the reply..


Interesting comment, can I ask why you make that statement?
Is it due to poor surge capacity on the tank?

or poor fuel pickup design?

or??

Callaway Chris
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Re: Acceleration hesitation

Post by Callaway Chris » Mon Jun 25, 2018 8:05 pm

Below 1/4 tank will starve the pick up in the tank. It will surge and buck. Also, as the tank ages, it could separate, giving a false reading as the bladder will no longer allow for the full 18 gal capacity.

If your tank does not hold 18 gal, beware.

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SurfnSun
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Re: Acceleration hesitation

Post by SurfnSun » Tue Jun 26, 2018 1:04 am

Massive torque pushing the fuel away from the pickup....fill’er up and let it rip!

puzzigully
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Re: Acceleration hesitation

Post by puzzigully » Tue Jun 26, 2018 7:14 pm

Thanks guys,

seems like a poor design that once the fuel level gets below 1/2 full, you start having fuel pick up problems??
I could understand if it was under 1/4 full

Anyone have any "tweaks" that may help?

I have a (non corvette) race car with fuel injection and have an external fuel pump and swirl/surge pot to eliminate this issue.
Fingers crossed, I don't need to go to this extreme?

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SurfnSun
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Re: Acceleration hesitation

Post by SurfnSun » Tue Jun 26, 2018 9:46 pm

Well remember the hp rating was only 230 when that tank was designed. The torque was 330ish. My 88 made 440/575tq at the tire...as long as I kept it above 1/4 tank I was good.

Callaway Chris
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Re: Acceleration hesitation

Post by Callaway Chris » Wed Jun 27, 2018 10:59 am

Please do not overlook the condition of the tank and your fuel pump sock at the pickup point.

puzzigully
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Re: Acceleration hesitation

Post by puzzigully » Wed Jun 27, 2018 8:38 pm

Chris,

good point, it certainly is worth the time to remove the pump/pick up assembly to inspect the condition of it as well as the tank....

And, no I wont use a lighted match to see inside the tank for any issues :nono

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BIGJOHN
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Re: Acceleration hesitation

Post by BIGJOHN » Thu Jun 28, 2018 9:48 am

Good idea about the Match
Some of the very early cars before the late 1920's had dipstick for checking gas level

:beer

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