How far would you guys spin a completely stock LT1 engine if you was running it at the strip? What RPM is the highest you guys shift at with the stock tune and rev limiter and stuff ... Speaking of which , what is the rev limiter set at on a stock LT1 ? ... If it is removed and everything else is stock would you guys rev past where it was or do you think the stock bottom would take a dive off the deep end ? I was jsut wondering cause im not one to beat on my car lol but the thought come to mind how high a stock LT1 revs too , and with out the limiter is it somewhat safe to spin past that even ? lol

 

after a point its useless to keep revving it that high, you need to keep it in the powerband, some off my fastest times where shifting 300rpm or so below redline

 

I beleive the stock limiter is set at 5750rpms. With a tune you could bump it to whatever you want but I wouldn't spin past 5900rpms with the stock springs. 6000 if your brave. Shift as high as it will let you take it at the track with the limiter.

Brad

 

factory rev limiter according to auto tap is 5771.
I seem to shift at 5715rpms according to autotap.

 

is it actually doing you guys any good to shift right there? i was slower when i shifted right before the limiter, the only thing i used that limiter for was launching off it! yes we had pics and proof that it can be done numerous times before you break something

 

When I was running the hot cam, I regularly spun my stock short block to 6300 with no problems.

-Dave C. '97 Z28

 

besides the fact that you can spin 6grand with out a problem, do you guys think it is really needed? i know this is off the topic but im wondering opionins now

 

My car ran best when shifted just a gnats hair before the limiter.

A lot of people think that LT1's don't like to be revved that high, but there's a few out there that do.

 

With the stock cam it might not be needed.

But what would really answer the question is figuring out whether or not the car will put more torque to the ground in 2nd gear at 6300 or 3rd gear at 4000. Whatever situation is putting down more torque is the way you want to do it.

-Dave C. '97 Z28

 

I don't think he was implying you'd break anything but you can run into valve float with the stock springs revving that high...with my car at the track I was shifting when my tach read about 5900 in first which is probably about 5700 realistically...then second was about the same then 3rd I shift about 5600 or 5700 on the tach so probably 5500ish.

 

I ran mine up to 6200 generally, but had 1.6 RR's. Thats where I got my fastest times...

 

Just depends on your power band...it does no good to rev past 6g's if your car isn't capable of producing power at that high of rpms.... I think the power starts to drop off at about 5500rpms with the stock cam...I'll beable to tell after this weekend after I get my car dynoed..

 

You will fiond that your best ET's on a completely stock motor will come shifting around 5600-5800. You should probably set the rev limiter to 6000 to be safe. Any higher and you will be slowing yourself down and wasting the motor. I made a lot of passes on my car when it was stock.

 

my best times is where i was shifting on the factory tach at 5800 to 6000. this is when i was all stock, even intake and exhaust. i know my factory tach off because i don't think the rev limiter kicks in on the factory tach until 6100 or so.

 

http://www.personal.psu.edu/users/b/...alculators.xls

OK, I took my stock dyno curve and using excel created a polynomial that fit very well. You can see that on the 'Dyno Data' worksheet. Taking the integral of that curve over the range of before and after the shift point will find your avg HP through a gear. This is based on a dyno run using an internally stock motor and stock exhaust with a borla 2.5" muffler, free mods, tuning, and a cai. The peak is a lil higher than a stock car, but not at much higher RPM. Using the worksheet "shift point' you can see the before and after shift rpms and the resulting average HP through that gear.

For a stock car shifting at 5800 (57xx) the rev limiter is best. Go ahead and plug in lower and higher shift points. You will see the avg hp drop. Ending up at the same Hp after the shift as before the shift will yield you the most avg HP.

comments welcome.

-brent

edit*
my stock tach was accurate on the dyno
My best time was shifting at 5800.