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Discussion Starter #1
88 TBI cars are hard to find, especially one with the original engine so you can be sure you are getting an 88 TBI cam.

NON 88 TBI cams are NOT hard to find. (What)Are the specs on a non-88 TBI cam...say for example a 90 or 92 TBI cam. Are they close to an 88...or should we just go with the hard to find 88 TBI or roller turbo cam from any year?
 

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Discussion Starter #3 (Edited)
Good post...I had previously read but the link to the real data is dead. This is the most valuable comment on the topic I have found so far.
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In '88 the turbo and the 2.2 TBI cam where the same .... as are all 2.2 TBI cams.
In '88 and '89 only the 2.5 TBI cam were retarded 4*, otherwise they are the same spec. After those two years, all TBI cams are the same.
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some nice things about the 2.2/2.5 turbo engine w.r.t. cams:

1. relative insensitivity to cam choice (like most mild turbo motors)

2. only two "families" of OE cam grinds - turbo and NA (incl. carb & TBI), with modest differences in cam lift & event timing between the

3. only one change in camshaft "style" from '81-95: in '88 the cam followers were changed from sliders to rollers; the cams are different: a roller cam cant be used with sliders and vice versa BUT the cam AND followers can be swapped (some exception -later motors didnt have oil feed adequate for slider - see DDG) ; also in '88 the cam belt and pulleys were changed from a square tooth profile to a round tooth profile (less noise), these can also be swapped +/- '88

many of us (myself included) run TBI cams in our turbo motors; gives more power UP, loses some torque LOW

so to summarize- pretty much any 88-95 cam will work fine :)
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and get an adjustible timing gear and play with timing on any 89 up TBI if your not happy right off the bat
 

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Discussion Starter #7
Was originally looking for an 88tbi cam to go on a turbo car. Looks like any TBI cam can be used if you also have an adjustable cam sprocket...which I do!
 

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Was originally looking for an 88tbi cam to go on a turbo car. Looks like any TBI cam can be used if you also have an adjustable cam sprocket...which I do!
so you cant or can use an tbi cam without adj cam sprocket?
i was told i have the 88 tbi cam but there is no adj c.s.
so if this is true is there harm not having one???? thanx guys...
 

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I'll throw another question in.
I bought an 88 TBI Omni for a parts car, I was going to use the
cam in my 2.5 turbo build, I removed the cam and gear from the parts car and
noticed it has a square tooth sprocket.
Possibly the motor/head was changed, but I don't think so.
I'm assuming I'll have to retard the cam 4 degrees via an offset key or buy an adjustable
sprocket, correct?
 

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Discussion Starter #10
Unfortunately there does not seem to be any documentation on the numbers stamped on our cams so if you dont know what you got in your hand...you don't know. Its easy to tell a slider from a roller but the rest is pretty much a guess unless you have the tools and equipment required to 'read' a cam. The 89+ (non 88) TBI cams have the same grind but are 4 degrees retarded from everything that I read so an adjustable cam sprocket or off-set cam key is required to put it back where an 88 would have been. It may or may not be even noticeable but most agree that the 4 degree difference one way or the other will move the power/torque band up or down 500 +/- RPM depending on which way you go.

So yes you can use the non 88 or 89+ TBI cam in any 2.2 or 2.5 turbo engine without an adjustable cam sprocket or off-set key and it is a direct swap as long as the receiving engine is also a roller cam.
 

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I can tell you from my experience I installed a roller cam in my GLHT, like 10 years ago
and didn't realize it would be 4 degrees retarded, I ran 14.30 ish at the track
After much frustration and alot of research, I installed a 4 degree key to advance it,
next time out 13.20's, that was the only change.
4 degrees on the cam makes a huge difference.
The cam was from a round tooth setup and I installed it on a square tooth setup.
 

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so how do you tell if in fact you have one cam or another?
is it possible just to retard your timing or advance without a different cam, will it still make a difference? sorry for all the dumb questions..
 

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Discussion Starter #13
Unfortunately there does not seem to be any documentation on the numbers stamped on our OEM cams so if you dont know what you got in your hand...you don't know.

If you have an adjustable cam gear or get the Mopar offset keys you can change the cam timing up or down several degrees. Depending on the cam and other engine options you may or may not get a performance difference that you favor more...or maybe less.

The comment made by Keith Alto above is a good synopsis of this concept. Some people want torque down low, some want it high...and when things are where they should be for better performance, it can only be measured at the track. In daily driving...on the street...it might be hard to tell much difference unless you have a lot of open road to rip up and down several times.
 
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