fuel pump energize time/demand

**BigM460** · 04-05-2015, 03:24 PM

Does anyone know if it is possible to lower or change the demand or energize time when the pumps prime, in the tune?

I'm having issues with blowing clamped hoses off in the tank at the time the pumps prime. Fuel pump demand goes past 50 to 75 and fuel pressure maxes gauge out at 90psi. Pretty sure it's much higher, as it takes over a minute of run time to come back down to a normal level.

Have had to change everything over to push-lock AN fittings, but still can only use clamps on the pumps. Hoping for a solution to this pressure issue at start up?

**whitey** · 04-05-2015, 04:06 PM

Why is it getting so high?

**justbob** · 04-05-2015, 04:13 PM

What pumps are you running, what style clamps, and what size fuel line?

Builder Of Badassery

**justbob** · 04-05-2015, 04:19 PM

Double post.

**BigM460** · 04-05-2015, 04:27 PM

2 340's, -8 fuel line outside tank forward.

**BigM460** · 04-05-2015, 04:32 PM

Pic of current

**justbob** · 04-05-2015, 04:36 PM

Is that 3/8" hose at the pumps and is that where it's blowing off?

Builder Of Badassery

**BigM460** · 04-05-2015, 04:50 PM

Originally Posted by justbob

Is that 3/8" hose at the pumps and is that where it's blowing off?

Builder Of Badassery

No, has blown off at every other connection, have changed it all over to the push-locks. Question is, is it possible to change the way the pumps prime? Runs perfectly after start. Just have the issue when I turn the key to start.

**justbob** · 04-05-2015, 04:57 PM

I'd imagine a simple adjustment to the tune. The reason I was asking about the hose was the pumps hardly have what I'd call a lip and they are 5/16". Zack told me a little trick he does where he widdles down a 1/2" long piece of the supplied hose to just a sliver and pushes the 3/8" line over it. Worked awesome!

I haven't logged start up pressure yet, but I could maybe tomorrow if someone doesn't get you your answer.

Builder Of Badassery

**BigM460** · 04-05-2015, 05:06 PM

Originally Posted by justbob

I'd imagine a simple adjustment to the tune. The reason I was asking about the hose was the pumps hardly have what I'd call a lip and they are 5/16". Zack told me a little trick he does where he widdles down a 1/2" long piece of the supplied hose to just a sliver and pushes the 3/8" line over it. Worked awesome!

I haven't logged start up pressure yet, but I could maybe tomorrow if someone doesn't get you your answer.

Builder Of Badassery

I'm hoping! I've emailed Jeff, but haven't heard from him yet.
Thought about installing a regulator just to use as a bypass/checkvalve. That is if it can't be fixed with tune adjustment.

**justbob** · 04-05-2015, 05:17 PM

He's off Monday's. Not sure what I was thinking earlier as I'm return style now so my pressure is right at 40. Sorry!

Builder Of Badassery

**martyo** · 04-05-2015, 06:06 PM

Originally Posted by BigM460

I'm hoping! I've emailed Jeff, but haven't heard from him yet.
Thought about installing a regulator just to use as a bypass/checkvalve. That is if it can't be fixed with tune adjustment.

Dyno day yesterday, Easter for him today.

He will get back in touch with you this evening.

**BigM460** · 04-06-2015, 01:57 AM

Originally Posted by martyo

Dyno day yesterday, Easter for him today.

He will get back in touch with you this evening.

How was the dyno day? Wanted to head down, but these issues took the car down Saturday morning. Good turn out?

**martyo** · 04-06-2015, 02:07 AM

Originally Posted by BigM460

How was the dyno day? Wanted to head down, but these issues took the car down Saturday morning. Good turn out?

Insanely packed!

This was our best dyno day ever.

**BigM460** · 04-06-2015, 04:41 AM

Originally Posted by martyo

Insanely packed!

This was our best dyno day ever.

Sorry I missed it. Hopefully will make the next one! Always a good time!

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