New engine is getting dyno tuned this week

Texas Speed built 416 LS3 bottom end, 68cc skimmed L92 heads, ~11.25:1 CR, 229/236 .629"/.615" cam, LS3 intake w/ Samberg over-the-rad snorkel, Hinson midlength headers into two 3" ID Magnaflow metal core cats, Y'd into a single 3" Racing Beat catback.

Mustang eddy current (loading) dyno.

Whaddyall think it will do?

 

630/545

 

Rear wheel/chassis dyno, btw, not engine dyno, feel free to amend ^^^ to account for losses

 

Didn't realize wasn't engine dyno.
Let's go with 576/496

 

542/487. Most(MOST) of the LS3 based strokers I've seen seem to be a bit lackluster in the peak numbers. Nice tq under the curve though.

My plan some day is a 4.185 bore/3.9 strokeERL/RED block. As much bore as I can on a minimal stroke. Just because it's a little different but not destroked.

 

I'm guessing it will be more in the 510-530 rwhp range, with 485-495 lb-ft. 542 or 576 would be kick-***! Stock heads, stock intake manifold, and single 3" exhaust, though...

Hopefully will have numbers today!

 

Ah missed the stock heads... I'm still not sure about how much of a restriction our RB 3" is. I think it would be interesting to see the difference between it and a cutout just in front of the CB just for comparison sake on you motor as it wouldn't matter as much on my 346.

 

Yeah, the basic engine setup is probably good for the numbers you and ZoomZoom posted above, but I think it would take further investment in headwork, a big throttle body, serious intake manifold, long-tube headers, and 3.5" single or dual 3" exhaust out the back, though.

We'll see how it goes soon enough...

 

515/470.

 

Was going to wait until I had good backup numbers from a Dynojet, but that might be a while so here's what the eddy-current load dyno spat out:
1st run: 430 rwhp, 421 lb-ft (impossibly low!)
2nd run, with settings modded to mimic Dynojet: 552rwhp, 541 lb-ft (impossibly high!)

Scaling the old engine's 424 lb-ft (Dynojet) torque by displacement and then scaling the new power curves to that, I get 485 lb-ft and 495 rwhp, for whatever that's worth...

Peak is at 6000rpm, right where I wanted it. Glad I followed advice and went with a slightly bigger cam...

I think it is running up against breathing limitations of stock L92 heads, stock LS3 intake and single 3" exhaust.

ANYway, the main idea was to fill in the low-end and midrange and have good street driveability. Honestly the previous 463rwhp power level was more than I could fully utilize at most of the tracks I go to.

Dyno run #1:


Dyno run #2 with parameters modded to simulate Dynojet numbers:


My *adjusted* rwhp and torque for the 6.8 LS3 vs. previous Dynojet results for the old LS2: