Cam Question: Square tooth vs. Round Tooth

[85GLHT-Omni]

A couple of cam questions...not to the typical ones, though...

87 and earlier cars got slider cams with square tooth sprockets?

88 cars got roller cams with square tooth sprockets?

89 and later cars got roller cams with round tooth sprockets?

What year did standard Omni's get TBI?

[turbovanman²]

87 and earlier cars got slider cams with square tooth sprockets? YES

88 cars got roller cams with square tooth sprockets?YES EXCEPT 2.5L GOT ROUND TOOTH

89 and later cars got roller cams with round tooth sprockets?YES

What year did standard Omni's get TBI?NOT SURE

[BigAl]

I think standard Omni's got TBI in '88....Im not positive though

[GLHSKEN]

Omni's NEVER came with the 2.5L....

[BigAl]

yep, this is from allpar

"In 1988, fuel injection on all Omnis and Horizons is standard. This engine developed 93 bhp. 1989 brings some changes to the engine which allow for quieter and smoother running. Major service pointers are highlighted with paint for checking fluid levels."

[GLHNSLHT2]

who said they did???

[85GLHT-Omni]

Thanks for the help.

So an 88 cam is best option from an 85 slider? In that, the 88 cam does not require an advance in cam timing. I'm currently running an 90 turbo I roller cam on a G-head, advanced 4 degrees and I'm satisfied.

For a given year, say 1990, is there a difference between the 2.5 TI cam and the 2.2 TII cam? or 2.2 TI cam (if there is such a thing)? Getting a cam is also a matter of blind trust, as there are no markings on cam?

I've read the debates and I'm not sure anyone cam is perfect. I definitely want to go with a roller cam, and getting an 88 seems like it saves on needing to get a adjustable cam sprocket. I also need a setup that will not be too lumpy and will pass emmissions.

[turbovanman²]

There is no way to tell what cam you have without having a shop with a cam doctor check it out. They say the 88 tbi 2.2 cam is the best below 20 psi.

[R/T]

What he said, as old as our cars are, you can never tell what cam it is...

Too many rebuilds.

[CletusJones]

what's better, square tooth or round tooth? My car currently has the square tooth variety and I was wondering if I should keep it like that when I swap a turbo motor in.

[turbovanman²]

what's better, square tooth or round tooth? My car currently has the square tooth variety and I was wondering if I should keep it like that when I swap a turbo motor in.

You have to keep what the engine came with, its not interchangeable.

[CletusJones]

You have to keep what the engine came with, its not interchangeable.

why? you can't just change the sprockets?

[turbovanman²]

why? you can't just change the sprockets?

Cam and aux shaft yes, crank no, there is no CB block square tooth and vice versa, no round tooth reg block.

[GLHSKEN]

who said they did???

LOL I was referring to Simons, 88 answer. Omni's got TBI in 87... IIRC. There were no more carbs after 86

[turbovanman²]

LOL I was referring to Simons, 88 answer. Omni's got TBI in 87... IIRC. There were no more carbs after 86

Lol also, but I never mentioned Omni in my answer,

[GLHSKEN]

Maybe I was pulling a Russ!@!!

[CletusJones]

Cam and aux shaft yes, crank no, there is no CB block square tooth and vice versa, no round tooth reg block.

Ahh, that's the missing piece! I didn't know it was cast into the crank

[turbovanman²]

Ahh, that's the missing piece! I didn't know it was cast into the crank

Its not, it comes off but the cranks are different on early and 89 and up. Although, the 2.5 tall deck has a round tooth but nevermind, stick with the belt the engine comes with.

[bobr19]

Although, the 2.5 tall deck has a round tooth

Theres the answer for non CB round tooth if you want to go that way bobr19

[iTurbo]

L-bodies didn't come with TBI fuel injection till '88. Up through '87, all n/a L-bodies were carbureated.