Since I rebuilt my 302 it's been running rough at low rpm. In fact to even make it driveable I need to idle it at like 800 rpm. I've been checking things across the board for a while now and I'm really starting to wonder if the stock fuel pump is up for the mods I made. First a little background: 83 Thunderbird that came stock with a 2 BL carb and mechanical fuel pump. During the rebuild I gave it E7 heads and a non-roller HO cam. Though it doesn't exactly parallel the HO conversion article on Coolcats, I'm mulling over the article's warning that a larger capacity pump may be required. So tomorrow I thought I might pick up a pump for a thirstier 302, maybe an F150 same year? Any thoughts?
ok what were you smoking when you thought the stock fuel system was up for those mods? cuz whatever it was send it my way lol. but i know its an area overlooked. but i would think a fuel pump off of a 351 would solve those issues. and since its the same block i belive it should swap out.
Lol. Touche. Well I know the 351 is similar but are you sure the pump is compatible? I guess I can compare them in store.
it should be cuz last time i knew the 351 eas based off the 302 block.
Well according to car-part.com the fuel pump from a 1982 F150 with a 351W is cross-compatible with the 302. Though the electric pumps are mixed in there too. As far as I know my car has no in-tank pump. I'll check it out tomorrow.
if its carbed i wouldn't think there would be one. was the stock pump mounted on the engine?
Yep. On the timing cover.
then that should be the only one. cuz i know on my cfi engine i have a high and low pressure pump. one in the tank and the other one next to the fuel filter. the one in the tank pressurizes the system and the one next to the fuel filter taks over after the engine is started. werd set up i know but if i did go with carbed i could just grownd the tan wie in the kick panel and use that low pfressure pump at all times for the carb.
Sweet :D No worries then.
nope none. i have all the worrys cuz id have to possibly upgrade my stock system for the sefi system or find a way to make what i have work with true sefi. more tunability and more power:evilgrin:
my thunderbird is using a holley blue electric fuel pump with an adjustable regulator for my 4 bbl. 306 c-4 project car. no problems at all.....
Yeah I considered buying an electric pump but they're pretty expensive compared to a simple mechanical piece. But I'm gearing up to put a big 4bbl on there in the future so maybe then.
If it runs OK on the road, the pump ain't likely your problem...
Whats the specs on that cam again???
The site is down. It does run good at higher rpms but given the nature of mechanical pumps that isn't surprising. The faster the engine turns the faster the pump will flow.
True, but it ain't gonna cause a rough idle problem... If you had lack of fuel at idle it would be OK for a few seconds after the engine is revved, then start to idle poorly. Plus it would probably have a flat spot off idle... A pump won't hurt especially if it is old, but you'll still be lookin' for your problem...
if ya really want...spend the $65.00 or so bux and get an EDLEBROCK fuel pump or I think holly has one to, or just loose the mech one ond wire in a low press aftermarket fuel pump
Lol. Well since I was last here I did indeed install a Holley 110 GPH mechanical pump. It improved throttle response but did not indeed fix the problem, sorry for doubting you Turbocoupe50. And I know I've said this everyday this month but I think I have it narrowed down. I believe it's the automatic choke. During the rebuild the manifold hose that was supplying it with heat snapped off the exhaust manifold and my uncle "fixed" it by jamming a smaller diameter slug into it and then giving it back to me to jam in the manifold. It's sealed nicely but now less exhaust flow is going to the choke to tell it the car is warmed up. Supposedly adjusting the choke could fix this but mine doesn't look like the type. Actually mine looks like every dam choke in the manual :yuck: It's got the exhaust hose, a wire from the alternator, and a vacuum diagphram on it too. The choke housing is riveted on. Any tips about adjusting this thing? Or is there a car with a fully electric choke that I can buy or scavenge?
Here's a picture. And yes the wire has current.
K forget that too...the choke is fine.