Gen IV questions/build

[DarkoNova]

Has anybody here built a gen IV engine?

I always planned on putting a FAST 102 intake on my LS1 before I sold it. Now I'm looking at getting an L92 and I planned on doing the same thing, along with a bigger throttle body.

But I talked to a tuner and he said a bigger intake and throttle body isn't going to do much for me.

I also saw a thread where people were saying DBW throttle bodies aren't as tunable as DBC throttle bodies and aftermarket larger ones are harder to tune.

Aside from that thread, I haven't seen any mention of DBW throttle bodies being any more difficult to tune or reliable than a standard cable one.

I'm just curious if anybody here has built one and has any opinions on bigger intakes and throttle bodies.

Also looking for advice building a nice L92 without stroking it.

[John McIntire]

I haven't heard the argument that DBC TB's are more tuneable than DBW. I know some tuners love and prefer to only tune DBW due to the fact that there's no slop in the linkage and WOT is WOT. DBW is the way to go.

I've heard from a few reputable tuners and engine builders that the larger TB's are not worth the hassle in tuning and every day driveability for the 3-4 HP they provide as they've seen. You're better off with a stock 90mm TB.

As far as the larger intake, I've read that the FAST one wasn't really that great and to go with the MSD one.

I'm sure someone else will chime in with their findings.

[btmatt]

built a gen IV LS3, TSP stage 4 cam, springs, headers, 90mm DBC throttle body, and cold air intake. Megasquirt ECU tuned by ourselves and make 500 RWHP.

I don't think you will see huge gains from the intake and 102mm TB unless you substantially extend your RPM operating range.

[Sbeck09]

It's about the supporting mods. If you put in a bigger cam then yeah, you need more air to support that so a bigger intake helps (heavily simplifying here). If you just throw in a stock motor then no, it's never going to be worth that amount of money. So this question can get either answer. As for DBC vs DBW, a competent tuner will work wonders with DBW since they have such precise control right through the computer. Yes DBC works great, but if given the opportunity just go for the DBW. The ONLY exception I've ever heard of to this was when boost levels got way up there.

Gen IV motors are pretty damn good out of the box. The pistons are the weakest link with rods 2nd in the bottom end. Better rod bolts and pistons will take you far. The top end is where the real magic happens. They LOVE to breathe so a cam, porting, and beefing up the valve train slightly will result in a motor that puts out well over 500hp with solid reliability. Hell the LS3 525hp crate motor GM offers just has a hotter cam than stock (430hp).

[DarkoNova]

Naturally I'd put a cam in it and some headers at a minimum to go with the bigger intake and throttle body.

But for now I'll leave it stock just to get it running and driving.

Thanks for helping to put my mind at ease with the throttle body deal.

[redbull396]

Would be a waste of time and money without above mentioned mods. FActory ls1 and ls6 intakes flow pretty well tbh. Throw a cam, headers, and some ported and milled 243 heads on it and you might be able to squeeze 440-450 whp out of an ls1. I've seen them higher in the corvette world, but the cam it takes to make over 450 isn't that great for driveability.