Did your FP rise when installing hotwire?

[ez at nova]

I thought I read in Kirban's catalog that FP would probably rise with the install of the hotwire kit. I did not see my FP rise at all really. Is this out of the ordinary?

 

[blackbuick87]

Mine did to the point the 237 reg could only hold it at 48psi. Had to get an adjustable

 

[ez at nova]

Originally posted by blackbuick87
Mine did to the point the 237 reg could only hold it at 48psi. Had to get an adjustable

I'm not 100% sure what you mean. you mean it went so high that your regulator could only lower it to 48?? (vacuum off??)
I wonder if the FP rising on the install of this kit is dependant upon the "strength" or holding power of your FP regulator? I think I'm running a Bosch unit. My FP was 48 - 49 vac off before and after the hotwire install.

 

[b231v6]

If you received more voltage at the pump the pump will speed up.Causing a slight rise in fuel pressure. That's because volume was increased.Did you check your voltage at the pump before installing hotwire. Maybe check the difference at different load settings on the battery i.e. stereo,lights accessories etc.

I beleive a hotwire is good for making sure you've got good voltage at the pump no matter what load is on the alternator.

If you don't have a significant difference with no load none will be seen.

Just say to yourself you have peace of mind that your pump will always have a direct path of good voltage.

I'm sure someone else has got their point of view.

 

[JDEstill]

It probably depends mostly on how bad your system was before...

The regulator is trying to maintain some pressure, and if it could do that before the hot wire, it should still be able to maintain that same pressure after. At idle for example, the pump gets more voltage, so it pumps more, so the regulator should open up a little bit more to send that extra flow back to the tank and keep the rail pressure the same as it was previously.

You are more likely to see a difference at WOT than at idle.

John

 

[ez at nova]

Hmm, ok. Well, I guess since my 02's are in the 760s on the high end of 3rd gear I should leave well enough alone.

 

[blackbuick87]

Originally posted by ez at nova
I'm not 100% sure what you mean. you mean it went so high that your regulator could only lower it to 48?? (vacuum off??)
I wonder if the FP rising on the install of this kit is dependant upon the "strength" or holding power of your FP regulator? I think I'm running a Bosch unit. My FP was 48 - 49 vac off before and after the hotwire install.

I mean it was at 45psi before the install and immediately after it went to 48psi. It was a Bosch 237

Just make sure you check it afterwards, the amount of increase (if any) will depend on how poor your factory connection/ground was.