ok all, so ill keep it simple

1985 Iroc Z28
305 LB9
Tpi
700r4 hd clutches b&m shift kit
3.23 9 bolt

the original motor blew to pieces before i got it, so i have a 1987 LB9 305, that ran well before pulled, could be an 86 i cant remember exactly, but its the roller version not the flat tapet on

the cam i have is a hydrolic flat tapet COMP cam with lifters....

since my motor originaly has roller lifters and cam can i just remove that tray and everything lifter related?

ALSO DO I "NEED" different valve springs, or are my stock ones fine?

also will this cam even work in my motor???? im guesing it will need to be dyno tuned to run right since i have headers a different rear and more smog crap

heres the cam i got from summit racing http://www.summitracing.com/parts/cc...-size/5-0l-305

 

That cam will work if you change the pushrods, lifters, and timing set... but why would you want to downgrade like that?

 

how would that be a down grade? isnt that cam way better then the stock cam in a 305 LB9????

and it cam with lifters, i was planning on using my old push rods in the roller motor if they wer the correct length

 

i also have a double roller edelbrock timing set

 

The roller push rods will be too short. A roller lifter is taller than a flat lifter, so your gonna need longer pushrods. You would be way better off to buy a hydraulic roller cam and reuse your lifters, and push rods instead of switching it all over to flat tappet.

 

i already have the cam, purchased it a year ago for a different motor but project changed directions

if all that i need is push rods so be it.


but im still confused on how that would be any kind of down grade tho...... its a "bigger" cam then factory and is one of several modifications im in the process of

 

By "downgrade" he is saying your going the wrong direction, sell your cam, and pick up a roller.....hyd flat cams can be a pain to break in, run specialized oil to make them live etc....they are for old farts who don't wanna change, or can't afford the initial buy in due to the expense of roller lifters. I fall into the latter category

 

understood, but after talking to summitracing, id be barely getting anything back for it so returning it for a roller cam is not happening i pretty much am stuck with it

 

Correct me if im wrong, but its a 85 IROC, factory hydraulic roller setups's were not used in these cars until 1987...

 

the cars an 85 the motor is an 87 iroc z28 305 tpi motor, heard it run in the donor car

 

Put the flat tappet in it, just make sure you do the correct break-in procedure and run either a ZDDP additive or an oil that already has it.

 

In that case, It would be a downgrade. from the sounds of it your stuck with it, the amount of money you are going to spend to make that cam work (lifters, pushrods, timing set etc.) will most likely buy you the proper cam. Duration seem's a little high to me for a 305 still. I'd pull both the intake and the exhaust back around 2 degree's

 

well.... i DO have an LT1 roller cam, its specs are 447/459 and 205/207 measured at .050, the comp is .444/.444 260/268 measured at .000, they seem very close but im not sure