Mayt13

Ok I have a 1990 I-roc with a TPI 305. This year of camaro have hydraulic lifters, and from its behavior I believe that one of them have collapsed.

When I was shoping around for a new set I fould that pep boys offered three packages, each including all 16 new lifters and a cam.

a CCS 2, a CCS 23 and a CCS 37

I found a spread sheet that described the difference.

My understanding of it is that the longer the Cam lift duration, the higher in rpms the engine will perform forfiting some of its ablity to idle.

I have three questions:
1) What are the orginal specifications for a TPI 305 cam?
2) Are the lifters specific (i.e. in length, compression rate, etc.) to the cam they come with?
3) If I remove a lifter from my engine, can I use it to determine what Cam I have in the engine? (may have been swaped IDK)

Thanks for the help

Orr89RocZ

iTrader: (20)

What trans you have? manual or auto. Autos sometimes got the small baby cam, somewhere around 179 deg duration I think? Maybe 190's. Specs are listed somewhere here in the tech articles on the home page.

The manuals got the same cam as the L98 which in 1990 may have been a 207/213 .415/.430" lift 117 lsa cam or the 202/207 .413/.428 on a 114.5 lsa.

The tech article says all 90-92 305's got the L98 cam which is a good little cam for a 305.

I wouldnt replace the cam with any of the pepboys cams

It should be a hydraulic roller cam and a good replacement lifter set is about 130 bucks now, and known as the LS7's. The LS1/LT1/L98 lifters all the same basically, except the latest LS7's used in newer LS motors have a stronger internal spring in the lifter that handles more aggressive cams. Not needed for you but they are good lifters at a cheap price..cheaper than other aftermarket replacements so makes sense to go with them.

They are not cam specific if hydraulic rollers.

hrspwr

iTrader: (3)

The lifters in your motor should be hydraulic roller and a cam replacement is not required (unless there is something wrong with the cam OR you want to change it anyway) when you change out the lifters. As Orr Said dont put a pep boys cam in it. Go with a decent aftermarket one if it needs ot be replaced.

Mayt13

The car does have a 5-Speed, It is not original equipment though; someone swapped it in after dropping the automatic.

All the tech section said was:
"the base engine for the IROC was finally the LB9 TPI 305 rather than the base LO3 V-8. However, G92 had to be specified now to get the better cam/230hp LB9 motor in the 5 speed LB9 IROC-Z. Previously, all 5 speed LB9 IROC-Z's got the higher output LB9.

and

5.0 liter TPI (LB9) with 5 speed gets revised cam for 230hp rating."

None of which identifies the cam by specification.

This is great though! I dont need to swap the cam, which is awesome, because that would have been a pain.

I wanted to go with the pet boys package because it was the cheapest,
This cars a daily driver and I need it back on the road.

Because I wanted to change all the lifters at one time, I need 16 of them, and even though the pet-boys option also included a cam, it was still the cheapest.

Autozone $16.99/ Lifter x 16 $271.84
O' Reillys $13.99/ Lifter x 16 $223.84
Napa $11.69/ Lifter x 16 $187.04

Petboys Cam and 16 lifters
CCS2 $ 94.99
CCS23 $103.99
CCS37 $184.99

So I figured I might as well get the right cam while I'm at it, just in case. I tend to horde parts because my car has 178K miles and stuff fails all the time.

PS Can you explain the notation your using to describe the cam, It's like tire code to me Idk what order is used.

Orr89RocZ

iTrader: (20)

Pepboys stuff looks like hydraulic cam and lifters not rollers. No way it can be that cheap. Id clarify with them to be sure. Either way id just buy ls7 gm lifters

Cam specs i said were duration at .050" of cam lift, then lift at the valve assuming stock rocker ratio, and then lobe separation angle.

TreeFiddy

Not understanding this - if it's got a single collapsed lifter and you need it back on the road cheap asap, why not just replace that one instead of the whole cam/lifters? And before you go to the effort, are you sure it's damaged, and not just mis-adjusted?

Mayt13

For anyone who may read this thread in the future:

Because the pervious owner was so negligent with his maintenance (either do to thin, old or insufficient oil) most of my lifters had ceased solid (no hydraulic damping). This made the car run rough like it had an enormous cam (almost like instaling solid roller lifters). They were so stiff, they actually punched my rockers out of adjustment (the way old school solid lifters used to). I picked up a set of edelbrock lifters dirt cheap of CL and installed them. Ran much smoother than before.