minocqa

could somone tell what model carter fuel pump and model holley regulator i would use for a 1985 rx7gs 12a stock carb
and where to get one
thanks

mar3

iTrader: (8)

Don't do it unless your ready for a fuel pump louder than your car...

WackyRotary

You really don't need that much fuel unless you go to a Aftermarket carb and header.

peejay

You need the 7lb pump and the 1-4psi regulator. I think they're both the "red" ones. I found out that everyone buys the 4-7psi reg and the 14lb pump at the speed shops so they don't normally stock the low pressure stuff.

Trust me the factory fuel pump is barely sufficient for stock HP, that's why you can tell when you haven't changed the fuel filter in a month - performance sucks because the pump can't flow enough volume and the slightest restriction on it will hurt power even more.

mar3

iTrader: (8)

Take a look at the thread "new fuel pump" by riffraff to see the dire consequences of this budget fuel pump....

WackyRotary

The reason I said what I said, is that one day when I bought my carb and header(same day in fact) I still had everything stock, except the exhuast was all hollow. The stock fuel pump always could keep up. I changed the stock fuel filter often. Then when I went to the mikuni/header, it was clear it couldn't keep up as it would start to hestate when ever the throttle was near wide open beyond 4K for any sustained time. 1st gear, it would get up to about 6K then the fuel would run out. I just don't see the advantage to a aftermarket pump/regulator on stock everything, I never saw any improvement when I did go back to stock everything and left the aftermarket pump/regulator on. ..Didn't seem to effect stock performance at all?

I do see the advantage of going to a higher volume fuel-filter so one wouldn't need to change it often. I have a high volume flow reusible one on my car. Really makes filter servicing intervals long!

theNeanderthol

iTrader: (1)

where can you find such a filter?

peejay

well i started noticing problems while my car was still stock...

BTW this isn't a "budget" fuel pump... the better the fuel pump you get, the NOISIER it'll be. Although I know someone who had twin Holleys in his Chevy and we were putting the engine back in and it wouldn't start. Duh, he had the fuel pump wiring out while the car was getting painted. Rigged up a battery to the pumps... WHIRRRR! Cranked engine some more. Still nothin'. No fuel in carb... gee is there anything in the tank? Dumped about a gallon into the tank (in trunk fuel cell... gotta love it) and the pump instantly went SILENT.

Cranked it again. It started. I was standing over the engine, and I jumped about three feet straight up when that sucker fired! (High compression 396 with an enormous cam and open headers.... the engine ran 9's in a Chevelle)

REVHED

Peejay's right. Back when everything was stock (except for exhaust) I would lean out really bad by the end of 3rd gear. The stock fuel pump was simply unable to keep up. As for the Carter being a budget pump...I've had both Holley and Carter and IMO the Carter is no more noisy, is made better and the mounting hardware is FAR superior. Hell, if you're worried bout the noise you shouldn't be driving a rotary.

WackyRotary

Revhed: Your kidding me right? Unless your stock pump was pumping less then normal amount or some restriction in the fuel system, possibly at the carb or pinched fuel lines or something of the sort, it should work just fine for stock...even if you have hollowed exhuast. I never ever had the stock Nikki float bowls ever run low on fuel with the stock fuel pump system. My experence tells me, with only the aftermarket carb was able to ever starve out the stock pump. It would hesitate very suddenly, not be mildly lean across the board, it would flat out run out of gas flow and missfire/nearly die suddenly!

Afterall all stock with hollowed cats, I was able to hit 120mph with the 85 GSL 12a, it must be able to keep up!?


To check it all is needed is to hot wire the pump and run a fuel line from the pump or run a fuel line off near the carb to a measured bucket. You should get about 5-1/2 gallons in 5minutes. If you don't get that, you know somethings restricting flow or the pump is faulty.

REVHED

Ok, the problem might have been due to the pump being weak or worn out. After all it was close to 20 yrs old but many people have posted the exact same problem of leaning out in 3rd or 4th with the stock pump on a stock engine. Why take the risk? And if you're gonna go to the trouble of replacing it you might as well get a decent aftermarket pump.

mar3

iTrader: (8)

It's budget because it's not gerotor and thus quiet yet powerful. Look up a Mallory, Granatelli, Aeromotive or Barry Grant pump to see the vast gulf in technology and performance between the named pumps and the noisy 'lil Carter........

DONNA

at the bottom rear drivers side of carb, there are two linkages, one goes to the accelerator pedal, the other one goes to a black casister looking thing attached on engine compartment firewall,passenger side, with a vacuum hose,,,,question is,,,what does the black thing do and when u remove the vacume hose there is a small jet that seems to be slotted whats it for, cant find a photo in the haynes,,but the two linkages are together on the same plate at rear of carb......

REVHED

If you wanna spend alot more money on a pump that is overkill because you don't like the noise of these "budget" pumps than that's fine.

hanman

Donna,
I am guessing the black canister is the charcoal canister. The carb vents into the canister and the charcoal absorbs the fumes. This is an emission control thing. I could be wrong with out more information or a pic.
hanman

yayarx7

Cruise control. Needs vaccum to function.

Hope that helps

hanman

Yaya,
Yea, your right. I didn't even think about cruise, it wasn't an option in my 1980.

jbontke

The slotted screw could be the idle mixture adjustment. It will not effect any fuel dilevery on the top end, just the mixture at idle.

mar3

iTrader: (8)

It will complement my K&N billet fuel filter ($64 US) quite well, thank you! Hopefully, no one that thinks the Mallory is an overkill fuel pump is running an overkill box called the MSD 6AL with extra coils that never came from the factory.....