I have a 305 TPI with headers and TrickFlow aluminum heads. I am going to replace the camshaft soon and was going to convert it over to a roller valvetrain. It seems that stock TPI cams have LSA of around 112-113. I found a roller cam on the Summit Racing website that looks good, but it has an LSA of 116. I know that TPI units like wide LSAs but is 116 too much? The cam has a duration of 196/202 at .5 so it should have good idle vacuum. I have heard of too little LSA, but can you have too much? Any thoughts would be appreciated.

 

The late L98 and LB9's have a cam with 115.5 LSA, at least that is what I got when I degreed one many years ago. 116 is on the high side, but it will work. Should idle real nice.

 

110 to 117 is a good C/L for TPI normaly wider the C/L smouther it going to idle.

Less over lap better the idle.

I running 111 C/L 8 dergees of over lap idles very smouth.

I wanted a nastyer sound my self but oh well it a sleeper.

 

Probably going to very lazy.
Don't they have something with same specs and a better LSA?
Stock cams have a LSA of 114 - 118 degrees, for economy. If you make the LSA 112 , the motor will idle and make more mid range torque than a cam with the same specs and a larger LSA

 

Thanks for all the replies. My current flat tappet has a 110 LSA and a 206/212 duration. It pulls 14.5" at 800 RPM. It ran VERY rich when I first installed the TPI unit, but after some tuning it runs ok. This is my daily driver so I am more concerned about streetability than all out power. I figured since I had the cam out, I would put something in more TPI "friendly". This roller I was looking at has more lift and less duration than my current cam. I was hoping to get the best of both worlds as in more power AND maybe pick up a few mpgs.

 

That's a very mild cam. Specs sound similar to a stock 350 TBI cam. A stock TPI cam would have duration similar to what you have now but on a wider ~114-115* LSA.

A good upgrade for a near-stock TPI engine (or a slightly warmed up TBI engine) is the factory LT1 cam. Specs are very similar to the stock TPI cam but with more lift.

 

You might want to look at the retro (I assume your 305 is pre-86/87) XE256 4x4 cam, specs: 206/210 111 LSA .458 lift. It has a tight LSA, but since it has very low duration, theres very little overlap. It pulls 18 inches of vacuum at idle, and idles like stock. I put it in because I was tired of crappy fuel economy with the large flat tappet. With the trickflows, it still gives good performance while not having much overlap. You might like it more than the small one you originally listed. I had a flat tappet with those specs, and I hated it. Way too much low end torque, no power after 4k.