adjustable fuel pressure regulator

[tubbyG]

my carb bowl is emptying when at full chat in 4/5th gear at 24psi

I have phase 1 fuel pump, and current carb spec is
2mm needle valve
1.4 s/s
standard main
0.9a/c

im looking at fitting an apr to overcome it, but wondering if this would be sufficient - http://www.ebay.co.uk/itm/Universal-...item1e6f8a7de6

does it just replace the standard pressure regulator, or would I plumb it in series?

are there any cons to having higher fuel pressure? or are there any other mods that can be done to the fuel supply instead

thanks in advance

[THE MASTER]

fit a fuel pressure gauge and see if the pressure is falling off with big boost. it should stay above boost pressure above carb at all times (about 4psi above).

any more could cause over filling of the float chamber . due to the neadle valve being open by the fuel pressure

any less will cause the float chamber to empty . cos the boost pressure is not letting the fuel in

a drop in fuel pressure can be caused by simple things that slow down the flow . like a clogged fuel filter also a clogged pickup in the tank, there is a little filter in the intake of the fuel pump . and also taking the boost presure from the incorect point that goes to the regulator can give you problems . the boost pressure line should come from directly above the carb and have no leaks


hope this helps

[soapymech]

im also looking at regulator and pump but for a nos system, my car is fueling fine at 20psi using a similar set up as tubbys but wondering about using the oe reg for the carb then adjustible for the nos fuel line as it has to have 44psi minimum can i do this? im using a phase 1 pump atm but think its not enough? cossie pump ?

[Logg]

I have a funny feeling that reg is for efi you'll. Need one of these regs

http://item.mobileweb.ebay.co.uk/vie...id=85089690703

I'm sure with a little looking about they can be found for about £45

[GTphil]

The regulator in the first post won't work for you as efi cars run at much higher fuel pressure than carb'd cars.

The one logg posted is the one I use on my raider, I also take the pressure reference from the compressor housing on the turbo, this set up coupled with an efi fuel pump does the trick for me and my carb spec is more or less the same as tubbys.

I read that a rising rate fpr for carb'd cars supplies fuel @ 1:1.7 ratio of air/fuel. However I couldn't find anyone who could tell me the enrichment ratio of the malpassi fpr in question, I did however stumble across something on a austrailian website that speced it as the above ratio. The standard fpr ratio is 1:1 fuel/air if memorie serves me right.

Both the standard and fpr009 malpassi regs are not ajustable, brigsy runs an ajustable fpr on his van and seems to get good results with that also.

I have never tested my raider up to 7k plus in fifth as I haven't got the minerals up to 7k in fourth after going right through the gears from frist redlining every gear change and my flote stays full with my set up.

Also the simple things like Col mentioned are worth keeping on top of, also the little gauze filter on the carb fuel inlet fitting can be removed. Make sure the fuel pick up is clean/clear and you have a fresh fuel filter.

[Logg]

Sorry i was on my phone the one I posted was the non adjustable.

But this one looks like the one me and Big Dan run.

http://www.ebay.co.uk/itm/FUEL-INJEC...#ht_500wt_1169


when running more fuel pressure you'll probably find the need to go back to a 1.7 needle valve

[tubbyG]

Thanks for all the advice
Changing the fuel filter will be the first step and go from there
I will have a proper look for a carb f p r once i get a chance. Internet on my phone is terrible

[tubbyG]

reviving this thread a little

I have renewed the fuel filter, bought a new uprated fuel pump from syntec and renewed the vac pipe connecting from carb to fpr, although I have left the fpr for now as I want to see if it was just my fuel pump on the way out - it was apparently a phase1 pump bought from CGB, is there any way to tell if it actually was a phase1 pump?

I have still not driven the 5 with these parts fitted as yet, so have measured the fuel pressure entering the carb at idle only. I am seeing 1/3 of a bar, or around 4.8psi of pressure at 800rpm

is measuring fuel pressure at idle sufficiant enough to determine if the fpr is working correctly, or do I also need to be monitoring it when on boost?

[GTphil]

You will also want to monitor it on boost, you might notice a difference with the new pump but my guess is you will need a different FPR also to stop the flote from emptying

[tubbyG]

thanks again Phil your input again on the fuel supply is much appreciated, cheers.

I will measure the fuel pressure once im on the road again - hopefully soon !

after that I will most likley be in the market for a fancy fpr

[Dave Reed]

im also looking at regulator and pump but for a nos system, my car is fueling fine at 20psi using a similar set up as tubbys but wondering about using the oe reg for the carb then adjustible for the nos fuel line as it has to have 44psi minimum can i do this? im using a phase 1 pump atm but think its not enough? cossie pump ?

Do you normally go to the Surrey meet or is it ace cafe I see you at? I can tell you exactly what you need.

[soapymech]

Do you normally go to the Surrey meet or is it ace cafe I see you at? I can tell you exactly what you need.

Yes dave I normaly do ace but have done surrey meet. I would have been in contact sooner only I have just finished putting it back together after blowing the h/g but that's done and am now getting the last bits I need to run the nos, basicly need a swirl pot,fuel pump and a blow down tube I now have funds so it won't be long. Would be great to get some pointers from you dave once I'm sorted as I'm in Essex most weekends so I could come to you if it's better too. Regards soap

[Dave Reed]

Yes dave I normaly do ace but have done surrey meet. I would have been in contact sooner only I have just finished putting it back together after blowing the h/g but that's done and am now getting the last bits I need to run the nos, basicly need a swirl pot,fuel pump and a blow down tube I now have funds so it won't be long. Would be great to get some pointers from you dave once I'm sorted as I'm in Essex most weekends so I could come to you if it's better too. Regards soap

Good stuff mate glad ya getting there.. I just didn't want to clog up the thread.. You can pm if you want.

[soapymech]

Realy appriciate that mate once I'm sorted with parts il be in touch

[gttjames]

Iv spottet this on ebay which i havnt seen before - would it be any good (better than a 'phase 1' fuel pump?)

http://www.ebay.co.uk/itm/2710396999...84.m1423.l2649

sorry to hijack but how do you measure fuel pressure, would you need to mount another gauge in the car etc?

[tubbyG]

I have no idea on that one.... does it give any info on flow rate?

I bought this pump
http://item.mobileweb.ebay.co.uk/vie...d=110604790467

To measure the fuel pressure I t'd in a boost gauge into the fuel pipe entering the side of the carb.


Edit: just seen the spec on the item description hopefully someone will be able to advise if that is sufficiant

[soapymech]

Iv spottet this on ebay which i havnt seen before - would it be any good (better than a 'phase 1' fuel pump?)This is a powerful pump but don't know about quality personaly I'd use a bosch pump.

http://www.ebay.co.uk/itm/2710396999...84.m1423.l2649

sorry to hijack but how do you measure fuel pressure, would you need to mount another gauge in the car etc?

you can use an in line gauge just to set it up or fit it in car I would say it's good to keep your eye on it to make sure it's 4psi obove boost pressure