My draw through turbo
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Re: My draw through turbo
Hi all I'm back. I've been reading and some people are saying I need a check valve on the boost line that goes to the boost sensitive fuel pressure regulator and some say I don't, are you lot using one?
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Re: My draw through turbo
Hi all I'm back. I've been reading and some people are saying I need a check valve on the boost line that goes to the boost sensitive fuel pressure regulator and some say I don't, are you lot using one?
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Re: My draw through turbo
Also pump jets 50 or 70?
- Chip Birks
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Re: My draw through turbo
Yes, you don't want it screwing with your fuel pressure while off boost.
- Piledriver
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Re: My draw through turbo
With a draw through carb, the engine is ALWAYS NA as far as the carb can see.Chip Birks wrote: ↑Wed Sep 20, 2017 3:55 pmYes, you don't want it screwing with your fuel pressure while off boost.
You shouldn't even need a boost sensitive pressure regulator unless your bowl inlet needle won't flow enough fuel.
If you are using a Weber carb draw through you can't really feed it over 3 PSI anyway or it becomes bad fuel injection.
(uncontrolled fuel leak)
IF you are running EFI, having it connected is proper (but not required) as the manifold vacuum effects the injector flow.
With EFI you can tune it either direct connected to manifold vac or not referenced or with check valve boosted.
(not manifold ref under vacuum may make tuning it a little easier)
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Re: My draw through turbo
I ran one......you can kinda make it out behind the stainless braided line above the orange battery line/above the aluminum intake.Chip Birks wrote: ↑Wed Sep 20, 2017 3:55 pmYes, you don't want it screwing with your fuel pressure while off boost.
'65 Bus with a JDM Subaru EJ20 Turbo
Built by Germans powered by Japanese and brought together by Canadians
Built by Germans powered by Japanese and brought together by Canadians
- Chip Birks
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Re: My draw through turbo
This is a sidedraft draw through fuel enrichment trick people have been doing for decades. Correct or not, it does what it needs to do float bowl is too small to provide an adequate supply, dellorto guys drill out the bottom of the float bowl to add capacity, they also add the pressure line to the regulator, with a one way valve, to quickly refill the bowl under boost. Good, bad or indifferent, its what we have done for a long time. If you don't do it while running a sidedraft weber or dell, the car won't run well under boost. Add that silly little line and the engine wakes up, makes a huge difference.Piledriver wrote: ↑Wed Sep 20, 2017 5:01 pmChip Birks wrote: ↑Wed Sep 20, 2017 3:55 pmYes, you don't want it screwing with your fuel pressure while off boost.
With a draw through carb, the engine is ALWAYS NA as far as the carb can see.
You shouldn't even need a boost sensitive pressure regulator unless your bowl inlet needle won't flow enough fuel.
If you are using a Weber carb draw through you can't really feed it over 3 PSI anyway or it becomes bad fuel injection.
(uncontrolled fuel leak)
IF you are running EFI, having it connected is proper (but not required) as the manifold vacuum effects the injector flow.
With EFI you can tune it either direct connected to manifold vac or not referenced or with check valve boosted.
(not manifold ref under vacuum may make tuning it a little easier)
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Re: My draw through turbo
Someone please help me out here I can't seem to get this right in my head.
If I fit a non return valve on the boost line going to the fuel regulator I under stand that when boost comes on the boost pressure over powers the valve and then the pressure hits the regulator and it increases fuel pressure BUT when boost decreases the non return valve will shut but surely it will hold some pressure in the line between the valve and regulator giving me the wrong fuel pressure?
If I fit a non return valve on the boost line going to the fuel regulator I under stand that when boost comes on the boost pressure over powers the valve and then the pressure hits the regulator and it increases fuel pressure BUT when boost decreases the non return valve will shut but surely it will hold some pressure in the line between the valve and regulator giving me the wrong fuel pressure?
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Re: My draw through turbo
Can someone send me a link to what check valve I need please
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Re: My draw through turbo
try the 70 pump jet,, here's a pic for you, it's just a one-way 'smog valve' of some type u can blow air thew it only one-way
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Re: My draw through turbo
But that's just a simple non return valve surly if I was on boost say 10psi and I suddenly come of the throttle that non return valve will close and trap some of the boost pressure in the boost sensitive fuel pressure line causing the regulator to produce to much fuel pressure?
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Re: My draw through turbo
Quit over thinking
It bleeds off the pressure
It bleeds off the pressure
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Re: My draw through turbo
Drill a tiny hole in a brass nipple if you want the excess pressure to bleed out.
I did that with my MBC when I built one out of a 1/8 inch brass Tee.
I did that with my MBC when I built one out of a 1/8 inch brass Tee.
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.
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Re: My draw through turbo
Ok so will this one do?
http://www.ebay.co.uk/itm/Non-Return-Va ... SwceNZTTA9
http://www.ebay.co.uk/itm/Non-Return-Va ... SwceNZTTA9