Kevin- I have never tried to rev to limit in neutral.. Maybe I should tomorrow, that may tell something..

 

I'm glad you won't rev it any higher. Unless you want to experience valve float. On my SS, it would shift at 6400 rpm WOT. On my Lightning, I shift at 5300 rpm. No point in reving it higher if it doesn't make power! Unless you like breaking parts. Sorry for the misinformation!!!


Dave

 

Keep it under 6500 Rpm, unless you change your valve springs. Your not going to gain anything past this. Valve float will kill any engine. These are not high reving 4 bangers, which I'm glad that Gm went this way. They designed a longer stroke/smaller bore for better low end torque then import designs. This means no reving to 7 grand for peak power. Look at the Civic SI, they have better peak hp but you have to rev the piss out of it. On four bangers, GM stuck to the idea of better lower/mid range power vs. all out power and I, for one, love it.

Dave

 

Dave- Thanks, Actually I only just made a couple hard pulls & watched it go to 6500 rpm, & I backed off a bit, being quite surprised.. I was guessing it would hit 6K & retard.

I know it's not making power any longer at that rpm, was just curious since I didn't feel a rev-limiter kick in..

 

I thought she was coming apart body wise at 6,500 rpm at 120+ mph ! Motor still had something just not very areodynamic .....

Best-O-Luck ,

 

As long as you don't make it a everyday thing, your fine. At those speeds, thrown rods, spun bearings, valve float, ptv contact can happen. My Lightning's engine with stock rods can spin to 6000 rpm but am I going to try that? No. The stock L's rods kick out under high boost/rpm/pegging of the MAF. I work in a machine shop and i'm just trying to save you some future machine work on your block and rotating assembly. I can't tell you how many engines we get, where someone was doing some high reving burnouts/races and toasted the lower end of their engines. Most of these were stock short blocks. Never had an ecotec in yet, if thats a good sign! Just a rule of thumb I live by, If it's stock, don't push it, rev and boost wise.

Dave

 

Very interesting.. my tests consisted of shorter runs, & I did the shifting.

Very familiar with Valve Float on HD motors.. Not a good thing.

I believe the Eco-Tec engine is an interference motor. So if something went wrong things could get ugly quick..

 

Yep it is an interference engine! Even with stock engines, you can have PTV contact.

Dave

 

Dave-

I have a small shop that I do machine work & build Harley motors, etc..

I'm not trying to blow my Eco-Tec up. Was just testing a new mod. I can say it passed with flying colors..

I'm in my 2nd year of ownership of my Panel, & these were the first times I ran it that tight.. LOL

 

78# springs help quite a bit in this department.