geoguy1369

iTrader: (2)

I'm doing a 6.0 block 4.8 crank motor. 9.5 to 1 compression with l92 heads. 88mm on3 turbo. What would you guys recommend for a cam? I like smaller smoother cams. Only turning 7000. Plans are 900 ish wheel. E85 with lots of street driving. Thanks in advanced

MY_2K_Z

iTrader: (1)

Can't wait to hear how it runs. If I fold up any rods in my ly6 I'll be swapping in for 4.8 rods since I have a set on hand

DavidBoren

My advice for cams is always to call Martin Smallwood and get a custom cam on a Cam Motion core. He will set you straight with exactly what you need and want.

Some questions, if I may. Why such low compression? You state you are going to run E85, so why not bump up the compression to ~11:1?

I really like the 4.8 crank in the 6.0 block, though, always wanted to build on. So I am very interested in how this works out for you.

geoguy1369

iTrader: (2)

I already have the piston and got them for a steal. Would have liked to see 10.1. And I drive alot. So if I end up going on a trip and end up on 93 I have a little cushion. I hope it will make the hp I want and keep tq down so I cab put it down better on the street

BMR Sales2

iTrader: (40)

It's going to be slow either way... :p
Hit up Texas Speed also and see what they have for you. They have some good off the shelf options and do custom grinds as well

1CAMWNDR

iTrader: (21)

Why an 88mm turbo for a 328" motor and only 7,000rpm? I would think a 69-76mm turbo with a proper turbine would make all the power you could want...

geoguy1369

iTrader: (2)

I don't see a 76mm making the power I want. Plus I don't have alot of money so if your talking a $1500 turbo will make close to a thousand in a 76mm that's why. Plus I have had my on3 88mm sitting in the closet for a year now.

Forcefed86

iTrader: (4)

Has anyone had good luck with the ON3 or VS 88's? Everyone I've seein installed so far has failed... I know of 4 that have locked up now.

SLOW SEDAN

iTrader: (13)

Mine worked fine... And the ones I see at the track work fine. Guys running 9's without effort in heavy cars on baby timing.

DavidBoren

Put some real thought into a good PCV system and an even better valvetrain and push for 7500rpms. Maybe even more. With some decent oil control and a really stable valvetrain, I see no reason not to cycle that thing noticeably higher than 7000rpms.

I think the big turbo would really appreciate all the rpms you are willing to give it, and I am sure you would enjoy the benefits of spinning the turbo higher.

With E85 and the low static compression ratio, you should be able to use a lot of timing, which can be used to your advantage.

Forcefed86

iTrader: (4)

I can’t think of a reason to destroke a 6.0 to run it to 7k @ 900whp levels? The factory bore/stroke will do that no problem and has done so many times on a 100% factory bottom end at over 900whp.

IMO Only reason to destroke would be to go well beyond 7k. Light weight rotating assy and valve train get expensive quick.



Did you run yours long? Put many miles on it? Seems like a great turbo and I was going to pick one up. The recent failures have me wondering if the bearing/shaft can handle all that compressor. The 4 I know of that failed all had thrust issues and locked up after a few weeks of operation. Initial power results were all great before failure.

SLOW SEDAN

iTrader: (13)

Agree on the RPM, I've turned sotck bottom ends higher and still living fine years later.

I got the On3 88 back in November last year, I ran it, sold it and its still going strong: https://ls1tech.com/forums/forced-in...m-results.html

gnx7

iTrader: (28)

Triple agree on why destroke and then not spin it higher.
My stock 3.622" cast crank was spun to 7800rpm for over 200 passes (1/4 and 1/2 mile) at well over 1200rwhp and what killed it was a 1-4th gear burnout showing 140mph+ on the speedo and it finally hooked up and snapped the crank. Otherwise the previous pass it went 195mph in the 1/2. Compstar rods and forged pistons. Stock LS3 intake/90mm TB, 88mm T4 turbo, 10:1 on e85.

Remember L92 heads have heavy valves.... so maybe sell those and just buy a set of LSA heads which are a better casting and have superior valves. LSA complete heads sell for around 600-800.

Here is a set of LS9 heads with Ti valves if you really want to not worry about high RPMs....
http://www.corvetteforum.com/forums/...ls7-crank.html

LJMSJohn

those intake valves will be a nightmare to keep under control... Too much intake valve and port for the displacement/ rpm/ Horsepower you say you want.

Put a 243 head on it... get the compression up a little bit more... put an LS6 intake on it... and use my stage 1 camshaft.

It has shown to peak right at 6900 in 4.8's... So it will probably peak about 67-6800 in that motor... and Rev out to your desired RPM peak well.

And it has the proper amount of overlap for that turbine wheel... which is not a lot.

oscs

iTrader: (19)

I never had a single issue controlling my heavy stock L92 valves even at 7300RPM. Trunion, BTR .660's properly shimmed and a decent cam with a not so aggressive lobe.

Serioussn95

iTrader: (1)

Look at the VS Racing S480 Billet knockoff...

DavidBoren

Absolutely put the 4.8 crank and rods with your pistons in it. And since you already have the turbo and the heads, I would use the same springs OSCS did with his L92 heads/valves, the BTR .660's, and run what you have with a custom cam. Tune it for all the rpms you can get out of it before experiencing valve float.

Run that for a while, get all the bugs worked out, and then upgrade what needs upgrading.