What does it take to run High RPM's

[MAXX IT OUT]

At what point does the LBZ ECM out weigh the LB7 and LLY ECM's for running higher RPM. I am looking at trying to get around a 5500ish RPM Red line, with a nice wide and useable power band. I am going to guess the musts are, Valve springs, push rods, a different cam, a keyed crank, and bigger injectors, but at what point does the electronic short comings come into play?

 

[DMAXchris]

Just curious, why do you want to spin it that high? Are you planning on running some massive turbo(s)?

 

[paint94979]

why is 5500rpm your goal? just curious

 

[MAXX IT OUT]

Not sure on what turbo set up the engine will be running, but the idea is to run autocross with my C10 powered with Duramax. I want to get a little more useability out of each gear.

 

[DMAXchris]

Not sure on what turbo set up the engine will be running, but the idea is to run autocross with my C10 powered with Duramax. I want to get a little more useability out of each gear.

That's gonna be cool! With AutoX, wouldn't you want more power down low to help with exiting the corners? I would think a snappy VVT that hits real low in the rpm range would be the ticket.

 

[ScreaminDuramax]

If he could incorporate the tap shifter then he could down shift in to corners and be up in the power range while exiting.

 

[DAVe3283]

...but the idea is to run autocross with my C10 powered with Duramax. I want to get a little more useability out of each gear.

Sweet! Having run my truck in an Autocross event (for the laughs), having more revs in each gear would be very nice.

That's gonna be cool! With AutoX, wouldn't you want more power down low to help with exiting the corners? I would think a snappy VVT that hits real low in the rpm range would be the ticket.

The problem with hitting real low is your trans will still want to downshift when you stand on the gas after a corner. When I ran, I ended up just forcing it to stay in 1st most of the time, or it would constantly hunt between gears, killing my time.

If he could incorporate the tap shifter then he could down shift in to corners and be up in the power range while exiting.

^^^ This

For the curious :roflmao:
[YOUTUBE]BHAN5r_UTjI[/YOUTUBE]
That was on a course designed for Miatas, so my truck was a bit too big, to say the least. :spit:
Edit: I came in 2nd to last. Which surprised me, because that meant some dude in a Miata managed to be slower than my truck, complete with 3-point turn!

 

[[email protected]]

You should see what Wagler is doing right now with the new broddix heads, I just watched a video of him hitting 2300hp@7300rpm. And he is expecting more. Oh, and he has 5 gear drivin cp3's on her.

 

[MAXX IT OUT]

That's gonna be cool! With AutoX, wouldn't you want more power down low to help with exiting the corners? I would think a snappy VVT that hits real low in the rpm range would be the ticket.

I belive i will have plenty of low end power still, but I want to be able to rap out a gear rather then upshifting, plus it gives the benefit of engine braking, essentially if a VVT is used. I have an LB7 wiring harness, but I hear that the FICM becomes a bottleneck to the ECM when trying to run high RPM's. I am just trying to find out at what point that bottleneck occurs.

 

[MAXX IT OUT]

If he could incorporate the tap shifter then he could down shift in to corners and be up in the power range while exiting.

I will be running an 4L80E, with some kind of paddle shifter or manual shift setup.

 

[gmduramax]

I would run either a stock turbo with a batmowheel twined with an S480. Or something that'll spool faster than that. Change your rear end gears to get the mph you want.

 

[Chevy1925]

I belive i will have plenty of low end power still, but I want to be able to rap out a gear rather then upshifting, plus it gives the benefit of engine braking, essentially if a VVT is used. I have an LB7 wiring harness, but I hear that the FICM becomes a bottleneck to the ECM when trying to run high RPM's. I am just trying to find out at what point that bottleneck occurs.

i believe the bottle neck happens around the 5500 rpm your looking at now from what i remember reading a while back. i thought it was something like 5200 rpm was about the best it could do. i could be completely off though

the c10 would be sweet to watch though!

 

[TROJAN366]

I would think a taller gear would make more sense than running super high rpms. Seems like the engine would be way out of it's efficiency range. If you had something like a Danville 3794 along with a tall gear ratio you would have nice low end response along with being able to hold the gear longer.....

 

[S Phinney]

You do realize that the parts necessary to run those rpms are not street friendly? Valve springs would have to be 160 seat pressure springs etc..

 

[DMAXchris]

I would def consider taller gears before trying to spin it to the sky. If you try to keep it between 3200 & 4k you should be right in the peak of the power band with a VVT.

 

[MarkBroviak]

Oh, I would so do that with my truck!!! Technically any of the ecm's can do it but you will have to run big injectors to keep the pulse down. I have engine dyno video's of an lly ecm doing over 6k rpm at full power without issues and same truck can swing 7200rpms easily. You will have to have a serious set of Wagler heads and light valvetrain to do it without issues and a good turbo combo. Air is the main factor that will allow you to turn those rpms.

 

[MAXX IT OUT]

So 5500 is a little lofty for a Goal? Overall power isn't going to be crazy. The gear ratio i have been looking at is 3.08-3.42 depending on what rear end i end up using .

 

[x MadMAX DIESEL]

Didn't Brayden say the lbz either fuels irractic, or stops at. 5200 or there abouts?

 

[SmokeShow]

Didn't Brayden say the lbz either fuels irractic, or stops at. 5200 or there abouts?

IDK if brayden said that or not but Greg Hogue did in one of his recent back-patting sessions.

 

[x MadMAX DIESEL]

He had some type of fb video on their test stand