Greetings. This is my first posting, thanks for considering. After much review, I am ready to build my first LS-series engine (this is about my 10 engine total). So far, nothing has been purchased, so all options open. The application is a bit different than all of you, so I hope you find it interesting. I am a huge boating enthusiast, and that is where this will be going. Not much marine market has converted to the LS-series engines yet, it is just starting now. Some of these may have been answered, but I wanted to re-post because this will be marine application (usually holding between 3000rpm and 6000rpm for a long time, like driving continuously up-hill in a car). Boat engine is always under load, and engine will use oil cooler as well (same as long running on engine dyno).

I would like to do a 6.0L single turbo motor for an open engine boat (hydroplane or jet boat style). From what I read, much HP can be extracted by just using a 6.0L motor (LQ4 or LQ9), LS6 cam, aftermarket springs and push-rods, single turbo, etc....

So, my few questions would be:
1. I plan to always run E85 fuel due to the 110 rating. Are the majority going with LQ4 or LQ9 motors for this (compression difference), considering E85 will be run only. I know A/F is about 9.8:1, and injectors will need to increase in size (about 30% flow increase).

2. Is there any advantage to run a different intake than the truck one? So far, this is my plan. Do not plan to exceed 6000rpm.

3. Since I will be changing cams, is any common aftermarket a "better" choice than the (used) LS6? If LS6 is not correct, please correct me. Once again, 6000rpm limit.

4. The famous "pick my turbo" question. I do not need low end boost at all, and really don't care about lag at all either. Given this, what larger size turbo and A/R rating would the band suggest? I do not need ball-bearing either, spool up time not important. I will be using a liquid intercooler (lake water). I plan to use flipped up truck manifolds, lot's of mounting room. I know nothing about mounting flages (T4, T6, etc..). Woudl like to have some reserve in turbo at top end if possible for future increases (not maxed out, coming on late OK).

5. Any cost or performance advantages of stock PCM over Megasuirt (this should be in PCM section, please excuse)?

6. Is anybody doing single turbo LY-6 motors? These (are new and) have variable cam timing. Does any cam maker make cams for this motor yet? Can this cam timing be controlled (tuned) by the common aftermarket PCM software available?

7. For simplicity, stick with the mechanical (cable) throttle body?

I am not on a budget, but and would like to use as many stock parts as reasonable (except turbo, wastegate, BOV, etc...of course). I have had such great luck with aftermarket cams, but I hear stock cams are great for turbo motors.......

Sorry for the length, thanks again for all of your experience. I know this has not come cheap considering time and money (investment).

 

For a budget.

Stick with the stock truck manifold, its a waste to do anything else.

LS6 cam and dual springs with good push rods. No need to waste money on another cam for under 900hp.

Cheap good turbo S400, will spool decent and allow for 800-900hp.

Stock PCM is in every way better then a megasquirt esp. with a custom 2-3bar o/s IMO.

Simplicity, there is absolutly nothing wrong with staying with the cable tb.