Anyone run a 6.0 on boost and 4.065 6.2 bore? Adding LSA internals and looking at 8-10 psi. Gonna get the block sonic checked.

 

I've run a 6.0 on boost and several LS3's on boost. There's nothing special about LSA internals. You get 9:1 static CR with no reason to go that low. Maybe if you have crap fuel and no access to meth injection. Static that low costs you power, fuel eco, and drivability. If you already have LSA internals, sell them for what you can get. Avoid the big 6.0 overbore and stick with the minimum overbore you need to clean up the bores. Absolutely no reason to go under 10.5:1 static unless you're going max effort on pump 93. Best bang for the buck is even higher static CR on flex fuel.

 

I have a motor that I was planning on pulling to sell but might keep and just cam swap.

It’s a LS3 forged rods and pistons with a .005 overbore. In a 6k truck the 216/228 with zl1 converter causing bucking at low speed that im getting tired of. Also was looking to go to hyper pistons for less wear since im not looking for more than 600whp.

 

What type of blower are you planning to use? What is the LSA on your camshaft? It doesn't sound too big at all.....unless it's on a very narrow LSA. My work truck has a 218/230 118+2 LSA with a little over .600 lift. That's in an L33 (aluminum block 5.3L). It has perfect manners with a stock converter and 4L80 transmission. Your issue might be tune related.

 

Yeah, I agree with Oldmotorhead, that should run better than that. I would have someone else(better) look at the tune before doing anything. As far as LSA rotator in a 6.0 iron, you can do it, but not ideal. I do love iron 6.2's, but with boost it's a crap shoot. The sonic check will tell the tale. If it were me with same equipment, I would run the 6.0 maybe . 030 over and buy cheap forged Pistons and h beam rods for it. I think it's better $$$. That being said, there is something to say screw ut and run what you have. On low boost, I think the iron 6.2 LSA is fine, but you have to control yourself and not get greedy later. TBH, on low boost, I would tell you to put better topend on it and sell the blower. All the added weight and expensive isn't worth it unless you want to really crank that **** to the moon. A nice 11 degree LS3 topend will rock on that, cost maybe less in the end.

 

Truck is a beast under WOT just still has some bucking issues. I’ve had a well know local tuner run it on the dyno. It made 375whp at 5200 and carried it as a flatline to 6500. Felt timing was off so had a remote tuner out of Texas tune it. Runs great but I drive the truck a lot and worried about putting the high miles on 2618 pistons. I planned to pull it and install into a c5 manual that I don’t daily. Has a 216/228 .600 113lsa.

For now I think I’m just gonna do .020 over and run some diy ported 706 heads. Opening them up for the larger bore. It will be around 11:1. Running a 206/218 .555 117+5. If I send them to TSP to get ported I may do 1.8 rockers. Have PAC .625 springs. I need something that is easy to daily and handle miles. Unless my deal on getting a used ax140 whipple comes thru lol.

 

If you want, I am going to have a set of shop ported 243 heads for sale soon, pretty cheap. They were on my TBSS and it flew. I'm going with a bigger head and not going to need these. LMK if you are interested and will get you some pics. FYI, I would not run 1.8 rocker at all. Those PAC .625 springs are not near strong enough to support that setup. You would be better off with a different cam vs a bigger rocker.

 

Thanks man. Let me know on the heads. So even tho the 1.8 would give the 206 cam less than .590 lift it would add too much stress on the spring?

 

DM me your contact info and will send pics on Friday. As far as the springs, there is way more to selecting springs than just max lift. The roller rocker idea needs way more spring rate to control the faster/longer motion of the valve and extra weight of the rocker assembly. It would be far cheaper to just get a better cam than try to make the one you have work harder.