Built motor Centri blower rev limiter setting?

Hey guys going to the track next week. I have a built 4.6 10.0 compression. Ported heads, comp stage 1 high lift blower cam with there springs. Car makes max power at 6950 rpm. rev limiter is set at 7300. it makes 740 at 6950 and about 710 at 7100. The pitch of the motor definitely changes above 7k. just seeing what's safe to spin these sohc motors or what other guys with high hp 3vs are spinning to. thank you

It's about the blower efficiency rpm. Not so much the engines rpm. Have you calculated at what rpm you max out your blower yet?

does comp have a suggested limit to RPM on the springs?

I'd think the limiter at 7300 is a good spot, you want to shift just past peak power, so shifting at 7100 makes sense to me.

On a built engine with a stock stroke I wouldn't think twice about going to 7500. There are guys here with similar setups and power level as yours revving to 7400+. However with power falling off at 7100, the blower may be running out of steam.
According to some sources you are to shift so that you land at peak torque RPM right after the upshift. The gear spacing in the 3650 is as follows:

1-2: 69%
2-3: 52%
3-4: 32%

Assuming peak torque at 4400 RPM, adding 69% to it takes you to 7436 for the 1-2 shift, 6688 for the 2-3, and so on. I haven't tried this at the track to confirm differences in ET versus shifting at "redline" in all gears because my local track is crowded and I'll get one run per hour if I'm lucky. Maybe you can test this for us.

I'm subscribing to this one!

I was told my build flattens out around 6K (due to lower compression?) but I'm very curious what the feedback is on this thread.

Once I add a 10-15% OD crank pulley and pulley down a bit with my Novi, I'll get her on the dunno and push it to 7K to see if power does drop at some point.

As JUSTA3V noted, I don't wanna over spin my Novi.

46addict said:

According to some sources you are to shift so that you land at peak torque RPM right after the upshift.

Click to expand...

That's exactly how we do it with the race car. We do look at a lot of info after each run and we may change a gear of two in the trans as we use a G-Force trans that we can change any of the gears.

The MT82 is a much better trans in this regard, notwithstanding the complaints on them so far. I'm not sure if they stem from people getting upset after buying a brand new Mustang only to find out they come with noisy/clunky transmissions or if they actually caused breakdowns. I haven't done enough reading on them.

But comparing ratios alone, the closer spaced gears in the MT82 saves you from revving to the moon on the 1-2 and 2-3 shifts just to stay in the powerband.

Sorry guys didn't give you all the information. I have a t56 magnum with the longer first gear. Also am running 50/50 water meth to lower iats because I'm pushing 20lbs of boost and at max blower rpm. So when I went to the track with no meth I was only trapping 135 which was low for 739whp and 3370 without me in the car. So I added a meth kit to hopefully help this issue run out the back door. I believe the comp spec sheet says 7k but everyone I talked to said don't listen to that. Also I was running 100 octane before and switched to ms109 and made 760 with no meth but turned the kit on and lost 20. But my tuners and our theory by 3rd and 4th gear we will be making more consistent power at top end because of the water/meth. We will see Monday. Last year I ran 10.4 @135 1.60 60 ft. Since then I have qa1 front coil overs double adjustable, bmr rear drag springs, willwood drag brakes, rear wheels are 5lbs a piece lighter, drag race alignment, and the meth kit. Goal is 9s!
Sorry got off topic but the tuner wanted to rev it more that's why 7300 rev limiter is there it will made over 700 up there so I say the higher I rev it the better it will be for the track. But just want to make sure I'm not going to hurt the valvtrain revving that high!

Got a dyno sheet? Where is your torque peak?