Josef

iTrader: (2)

I am about to install stock 243's and a fast 90/90 set up. Currently running MS3 cam with comp springs and rods. Will I need to upgrade my fuel injectors and if so by what. I would like to stick with stock for now at least. And the springs that are in my 241 heads should be able to be swapped to the 243s no problem right? And last but not least the lifters will be replaced, but should I stick with stock or upgrade?

ws6fitz

Should be ok with stock injectors, have a couple buddies running pretty much the same setup with stock injectors. You could go with something like a 42# or something if you wanted to.

slo_lt1

iTrader: (2)

Itll be ok with stock injectors but if it were me id run 42#er's.

boostedbird38

iTrader: (7)

Since you're not adding a cam with higher lift, i'd say your lifters and springs would be ok.

the 243's should give you alot more flow over the 241's, especially with the cam already in.

good luck, let us know how it feels

garygnu

find a injector calculator and figure out what you need .stock injectors #28 are maxing out past 410 rwhp,36# should work.get a tune first before driving it.

Josef

iTrader: (2)

Thanks, I'm going to run the stock injectors and rails for now. Maybe when the moneys good I will up grade to 42s. But I'm still wondering if I should go with stock lifters or up grade to LS7 lifters, or after market rollers. I'm hopeing to get my installs done next month still trying to figure the best gasket brand and if I should get a different thickness to raise compression. Has anyone done that? I will be going with arp bolts and change plugs to ngk555. I have msd wires but stock coil packs. Any opnions or advice would be great.

garygnu

the stock fuel rail will work fine.only get new lifters if your motor is hi-mileage.get a push rod checker to find the correct length .stock rockers work fine,get compcams trunnion bearing upgrades.get GM MLS head gaskets.keep the stock coil packs,msd coils are waste of your money.

nolo200

iTrader: (3)

upgrade them if they have a few miles on them...or have them cleaned...i'd upgrade to some 39# or 42# anyway though.

SOMbitch

iTrader: (8)

I would look for some Redtops in the classifieds. They will flow 36# at our fuel pressure and you should find a set in the $125 range..

Yeah stock LS7 lifters will be fine.....

Josef

iTrader: (2)

Well I broke down and asked the shop to go ahead and port and polish the heads. They are going to put some LS7 lifters in it and install the fast 90/90 this week. I want to get 42#ers but the money is not letting me do it. But when I do get the car back I will have that LS6 intake and Shanner S2 up for sale maybe that will generate the cash I need. Just not looking forward to drive another 2 to 3 hours just to get another tune when I do install the injectors.

JM0523

Better safe than sorry, id do them just to insure that sweet new setup you got isnt going to blow up.