https://www.roadandtrack.com/car-cul...-to-11000-rpm/

 

GDAMNNN.....Reminds me of some of my Banshees...

 

Technology and improvements are still coming for the LS platform.
In the next 5 years or so it will be interesting what we will witness.

 

She was a SCREAMER! Gearhead music at its finest!
He mentioned it was 358 cid. So obviously a short stroke LS7. I am EXTREMELY curious as to the valvetrain components used.
Let's hope/pray this knowledge trickles down to the gearhead masses
BTW, EFI University has GOT to be one cool place to work!

 

I'm guessing it had to be stroked down to spin that high but the power made was quite impressive. No offense FORD but lets see a Coyote pull that one off!

 

Dragzine had an article from 2018 with a lot of info. Probably a lot of the same bits since then.

https://www.dragzine.com/tech-storie...s-race-engine/

 

Billy Godbold from Comp designed the valvetrain. Cam lobes are custom for this engine. He spent a couple years in development making sure all the components would work together with gobs of hours on a spintron. Intake pushrods are 1/2” exhaust pushrods are 9/16’’ Exhaust pushrods are larger (stronger) because exhaust valve is opening against cylinder pressure.Cam specs are 288 and 308 degrees at 0.050 duration and 1.045-inch loft on the intake. The lobes were placed on a much larger 60mm core actuating a Jesel 0.937-inch diameter lifter with a 0.975-inch diameter wheel. Lifters are wheel guided units.

The Jesel rocker ratio is 1.9:1 and leverages against a PSI valvespring with 410 pounds on the seat and 1,200 pounds open. If you multiply 1,200 pounds times a rocker ratio of 1.9:1, the pushrod is working against almost 2,300 pounds of load.

Valvesprings lost control at 11,300, which is why the rpm is “limited” to 11,230ish. Springs are changed after every pull. I’ve heard Billy is working with PSI, who made the springs, in development of a better spring to shoot for more rpm.

Shaft rockers of course, I believe Jesel Mohawk units.

EDIT...Kent treed me...

 

Che70velle, thank you so much for laying all that out! Just shows what a truly focused build involves.
I never would have believed how specialized some of those pieces are. Springs lasting ONE PULL!
Hearing that engine pull to over 11k RPM was pure mechanical symphonic music!

 

On a similar note, nascar cup engines of today utilize non-adjustable rocker arms...what!!! They set lash with pushrod length and lash caps. The adjustment cup mechanism has been removed in the name of reliability and weight, even on the pushrod side of the rocker fulcrum. Yes, solid roller camshafts. Most shops are using T&D stainless rockers. Fewer moving parts means more reliability.
And some guys here though Darth was crazy when he set his valvetrain up...shame shame.

 

Agreed, although I believe Thunderstruck did it first here on tech with prompting and advice from Kip @ CamMotion.

 

Thunderstruck was the first that I saw, but it was so long ago I’m not sure most here would know. He doesn’t come around much. He posted recently and it was a surprise to many of us.

 

Blasphemy!

My guess is 4.8 crank and bored out to approx 4.175

 

Yes. I followed his thread. It had all the info you needed

 

I saw the thread and thought, "LS7 to 11+k/rpm?" Then I hear "358cid". Oh OK.. I knew it had to be short-stroked...
I hope Thunderstruck is doing OK...

 

Sounds like the 5.3 in my GMC when the ol' lady has it stuck in a snow drift...

 

Did it live to tell about it?

 

They're going around there. Michael Washington just went 8.47 @ 157 with a naturally aspirated, production head, Ford intake, stick shift yote.

 

Yeah still not that many rpm, just a gutted Fox. Its not like a 5th gen weight going 8s