What cam are you going to throw in this? Probably going to want something a little bigger than stock to compliment them heads.

 

Going with a turbo cam. Looking at Lil John, Brian Tooley, Tick, or Advanced Induction grinds as possible choices. I don't want something with a really aggressive lobes that's hard on the parts so that plays into the decision. Also, looking for great streetability. As for as duration goes probably somewhere in the 22x/22x 60x. lift range unless unless the cam maker suggests otherwise.

 

Another question about the flowbench results... why do they only test to .600"? Is that limited by ptv clearance? Were you still planning on getting custom pistons?

 

TSP just spec'd me a cam, 224/228 .600 114 lsa 2deg
(5.3 s475 t56 3500ish lb car)

Hopefully this helps you

 

3.9 bore size.

 

have no idea why they only sent to .600" but yea i'm still going with a custom piston to put me around the stock 9.5 scr range.

 

yea, something in that range is what i'd be looking. let us know how you like it. how quick does that s475 spool?

 

Why get custom pistons with such low compression? Are you stuck using **** fuel?

Higher compression, say something mild like 10.5:1, would help with spool and throttle response and torque production.

Low compression for boost is small block Ford tradition, it's absolutely unnecessary in the LSx world. Lots and lots of successful 11+:1 compression ls motors running plenty of boost.

Just make sure your squish/quench and tune are closer to perfect.

 

Perfect is dangerous since things rarely go as planned with these builds. I can get 93, those 10.5+ compression ratios are for like E85 at my planned boost levels 15-20 lbs. I'm comfortable at 9.5. I don't want this thing to go kaboom because of a such a small margin for error.

 

Things seldom go as planned, very true. So you are smart for giving yourself a safety margin. Ported heads and custom pistons led me to the dangerous assumption that you were going to burn corn.

15-20psi on pump gas warrants a drop in compression, for sure. Glad to see you have your ducks in a row. Carry on, and keep us posted.

 

Its no where near running haha but ill let yah know.

 

I think my walls need a little hone so im going to get that done and have them check all the tolerances and stuff. IF thats all good then hopefully i'll be on with my build like you! Thanks for the advice!

 

Do you know how big of a cam the stock lm7 heads can handle before your looking at a new valvetrain/pushrods etc

 

Thanks for the nice head photos. Pretty revealing.
And good for you choosing great heads for a turbo motor, it matters.

Your hot side pipe sizing, layout, and exh housing will determine spool. That along with fueling and timing from pre boost through 3 psi or so.

After dialing all that in on my car, it actually spools too fast for the track conditions we normally see....😊

Have fun.