best FPR and pump

MightyBoy tech questions and answers.
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bswift16
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Joined: Mon Sep 26, 2005 3:34 am

Am about to go shopping for FPR and fuel pump
any sugestions on which ones ,best combo??
cheers :)
willing to prove red ones go faster
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Brayden
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EFI or carby? Whats the setup? Details go a long way. ;)
F8B EFI turbo - Three pots and a snail.
bswift16
Posts: 131
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oops :oops: going through a charade turbo carby with a supercharger for boost
willing to prove red ones go faster
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Brayden
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In which case you'll need a low pressure FPR designed for carby turbo/supercharged setups, and as far as I know Malpassi are the only manufacturer of such a product. Be sure to get the carby turbo version though, as it has the right ratings for lower fuel pressure. You could technically use the original Charade FPR, but I prefer the adjustability of the Malpassi unit.

As for fuel pump, you only need one capable of producing a handful of PSI more than whatever boost you're running. So if your charger puts out a max of 7PSI, then you'll need 12-15PSI of fuel pressure at maximum boost, with about 5-6PSI at idle. Most EFI pumps are designed to deliver 40+PSI, so you'll only need a mildly powerful pump. I tried the equivalent of a VL turbo EFI pump with my Charade carby setup and it was complete overkill - resulting in massive over-fuelling.
F8B EFI turbo - Three pots and a snail.
bswift16
Posts: 131
Joined: Mon Sep 26, 2005 3:34 am

cool i was looking at the Malpassi rising rate unit and a Holly blue pump that puts out abot the 15 psi mark. as for boost i havent worked out the max boost i can get from my AMR300, but i only want between 7 and 10 anyway im not building a drag car here :D
willing to prove red ones go faster
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Brayden
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7PSI is all that I would run on a stock F8B with a carby and standard distributor. Any more than that I found was causing issues.

Also be aware that depending on pump choice (flow rate AND pressure) your fuel return line mightn't be sufficient to handle the recirculating fuel at idle, so you'll either have to run a new line or set up a relief system as Colin and I have done. Essentially it is a loop that transfers excess fuel back into the pump inlet, but with a valve that closes of the system at wide open throttle.

Ahh yes its all fun and games.
F8B EFI turbo - Three pots and a snail.
bswift16
Posts: 131
Joined: Mon Sep 26, 2005 3:34 am

the motor wont be stock im haveing it built by the engine guys to handle about 12 to 14 psi. as for the fuel line im going to upgrade the return to handdle the extra fuel. do you think i will need a larger delivery line or will the stocker cope??
The distributor is my next big challenge, ill probably leave it stock while running in and treating the motor kinda nice.but after that ill get some pro's to have a look at it to see what is best for my set up. would like to go elec but i know thats a big ask.

and YES YES the fun and games :D :D
willing to prove red ones go faster
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Brayden
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If you leave the distributor unmodified on anything more than 3PSI you'll kill the motor before you make it around the block. ;) Detonation is a bitch.
F8B EFI turbo - Three pots and a snail.
bswift16
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well that would sure suck :( any idea on what i should look at gettin done to the distributor???

and stock fuel line to the carb ok?? :)
willing to prove red ones go faster
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Brayden
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Stock feed line should be fine. Distributor needs to be modified to cancel advance, and add retard on boost.
Then you set the base advance higher to compensate.

Essentially you weld the shaft solid, then turn the vacuum advance into boost retard. ;)
F8B EFI turbo - Three pots and a snail.
bswift16
Posts: 131
Joined: Mon Sep 26, 2005 3:34 am

cool will look into that :) i was thinking that because supercharging was a constant boost set up the distributor would work like when n/a, because there is no sudden gain in revs and power as with a turbo.
but i aint gonna take the chance with all those $$$$ im spending :D
willing to prove red ones go faster
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Brayden
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Any boost in the system requires a reduction in distributor advance, the only difference between a turbo and supercharger is the 'curve' of delivery. ;)
F8B EFI turbo - Three pots and a snail.
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