Ok guys Im going to be putting in the CC503 cam and 1.6RR in 45,000 mile motor. The car has about 114,000 on it and as far as I know the pump has never been replaced. Do i need to get a bigger pump and injectors for the up coming upgrades?

If I do what in tank pump can I go with? What size injectors should I get? Will I need to get an adjustable fuel pressure regulator?

I know its a lot of Qs but Im putting some decent money into the valvetrain and dont want to short change the motor on fuel.

 

Your stock injectors will be fine.. Have it tuned though. You could replace your fuel pump for lets say a holley/walbro in-tank unit.

 

The pump should be ok i still have the stock pump that has 200+k on it with my stroker. I would upgrade the injectors size really depends on your future goals for the car like nitrous and what not. I would go with 30s for that cam and they should be good if you deside on a little juice. I have a set of ford svo 30s for sale with less then 300 miles on them

 

Larger injectors wouldn't really matter unless he is planning on going with a dry kit. The stock injectors will be plenty for the cc503.. Buddy of mine ran and tuned his old 383 with stock 24lb injectors and they were at about 90% duty cycle..

 

Both will be just fine with no issues if they are not already a issue. But Id recommend a 255iph pump anyway like the racetronix kit in the near future. IMO

 

i ran fine on a gm847 with stock injectors and pump. if you change the pump do yourself a favor and upgrade the wiring for it too.

 

Well that is some contradicting answers. Heres what Im thinking, I will be dropping the rear end to paint it all up and look pretty as well as install new springs so I might as well upgrade the pump while Im there. I was looking at the holley unit anyway.
I will have a mail order tune done when I put the cam in, will I need an adjustable fuel regulator as well to run the extra pressure from the holley pump?

Why should I upgrade the wiring as well? Is that a common problem? What are you asking for the SVOs?

I will not be running nitrous now or any time in the future. My feeling on nitrous is, its like dating a hot chick with an STD, you want to hit it but your afraid of whats going to happen when you do.

 

I forgot to ask, the motor thats going in is a b body motor (I will be installing a fresh pair of 643s on top of the b body short block), do those have different injector sizes than the f bodys?

 

The b-body injectors are slightly smaller (not sure if they're 19 or 22lb). You will not need an adjustable fuel pressure regulator. A mail order tuner (such as pcmforless or madz28) will usually recommend a larger injector (for the sake of not risking maxing out the injectors, even though you probably won't). Do the fuel pump and you should be good. If you find some stock f-body injectors those will be plentiful and won't break the bank. Good luck

 

id recommend a fuel pump/injector upgrade. you really need to see where your injectors max out at. if they are close id upgrade to at least the LT4 injectors (28 lbs/hr compared to 26). if your fuel pump is fine id leave it alone, but if you do need injectors you should upgrade it

 

@ 6500 RPM my duty cycle was like 85% on the stock injectors. it was close but acceptable since i wasn't planning on whacking the motor with nitrous anyway. the reason i suggested upgrading the wiring is because you could be one of many that swap out for a higher output fuel pump just to realize that the power getting to the pump was already barely enough to keep the stock pump happy.

 

Well, I think Im going to upgrade the pump to a holley in tank unit. Who makes the wiring harness upgrade and where can I price one at?
So should I just upgrade to a stock F body injector since Im not going to juice it? Or should I go with like a 30lb injector?

 

The stock ones are fine. A quality adjustable fuel pressure regulator is a good upgrade.

 

i put in 32s with my 503 with a stock pump. good to go sir lol. but there right either way stock should be fine, sense ur in it go for it and upgrade idk about the harness. but if uw anna do injectors anyway i got some stock fbody ones with 150k that ive never had a problem w

 

B-body LT1 injectors are 24 lb, same as F-body.
You're injectors will handle that 503 cam, no problem.

 

Pump will be fine, a set of 30 or 36# injectors might not be a bad idea since the stock ones are have 114k on them.
I'd rather be slightly too big than on the edge.

Leave fuel pressure alone, let the tuner take care of adding/removing fuel.
You'll just cause yourself headaches down the road.

 

I am going to side with the majority, your stock pump and injectors should be okay. If you want to have room to grow, 30lb injectors and a 255 intank pump.

 

I ran a 236/242 cam on stock injectors just fine. Peaked around 85% DC. No problems.