thinking about doing a twin turbo tpi. wondering what cam i should use. would prefer off the shelf if possible. any help is appreciated

 

Combo specs please. Engine, turbo's, gearing, car usage, desired HP output, etc etc.

 

Why the missing 'g' on your words? A nice turbo cam should make some power in that thing.

 

Engine: 355 SBC
Turbos: .50AR Trim T3/4 V Band
Gearing: 3.73 rear, stock LT1 T56 trans
Usage: Street/Strip (mostly street)
Desired HP: 650-700

Hydraulic Roller cam desired.

 

Check out ststurbo.com a lot of people on this board have them and love them, look them up.

 

If we're talking about ebay turbos on this motor, you're going to need to keep a mild cam, and low compression (~8.5:1) with around 20psi boost to beat the TPI intake. maybe a turbo designated cam with no more than 216duration @.050" lift. with too high a powerband, you'll be spinning the turbos way out of efficiency at flow rates needed for anywhere near the desired power output. I actually reccommend the restrictive TPI intake for these turbos because they are way more efficient at relatively higher boost levels for given flow rates. I've logged IAT's to estimate efficiency as well as measured the compressor wheel and compared it to a garrett TO4E 46 trim compressor flow map.

 

I've got a MiniRam on it, so my powerband is up higher than the normal TPI intake.

 

Well if you're planning to use ebay turbos, i'd shoot for a little lower hp goal. maybe 550hp (about 12-14psi boost).

 

I'm using a pair of Garrett turbos from ATP Turbo, here is the link
http://www.atpturbo.com/Merchant2/me...egory_Code=TBN

They will be mounted on BBS headers.

 

Good rule of thumb for a turbo motor especially a sbc is to run a single pattern cam. Split profiles can work effectively if dialed in perfectly but a single pattern with at least 114 lobe seperation is good. If you have the parts to flow to high rpm don't be afraid to run alot of duration.

 

That is just a general "rule of thumb". He would be better off looking at the cam card for the timing events.

Here is a another rule of thumb...one that I prefer. Set the intake duration for the RPM range. Set the exhaust duration and LSA for the exhaust on the vehicle. More restrictive exhaust requires less overlap. So for a big turbine pick an exhaust duration & LSA like a good flowing NA exhaust. For a little turbine spread the LSA and shorten the duration. Watch LSA for the general HP curve (peaky vs. broad).

 

Looks like you're doing your best to make it as difficult as possible for someone to give you a real recommendation.