Since I got the EFI system running pretty good a couple weeks ago, I been wondering why, whenever I get on it, it starts spitting and popping just when it's really feeling good.

While I was driving it today, it dawned on me...

The first stage of the rev limiter (random spark cutoof) is set at 5500...:o

I'll need to change that. Things happen REAL FAST in first gear this year, makes it hard to think.

First stage?

So, what will you be setting it at?....6500?

First stage?
Ya, there's 2 rev limiters in the c950, first stage is a random ignition cutout, second stage shuts off the fuel.

So, what will you be setting it at?....6500?
hehe, ya thereabouts...

What do you guys think, how high will she spin?

Bottom end is an internal balance 383, scat 9000 crank, 2 bolt w/studs, 6" rods, forged pistons, balanced.

Good stuff is AFR 195 heads, Ede Tarantula intake, holley 900 cfm injection, 1 5/8" headers (soon to be 1 3/4") with 2 1/2" full exhaust. Valvetrain is voodoo hydraulic roller, 232-239 @ 050", .530 / .550 lift, 110/106, pro magnum rockers, very good pushrods, 135lb on the seat, 330 over the nose.

She feels real good reving up, I can't wait to make that little adjustment. I need an autobahn or something. S**t happens to fast in first, second is good for 80mph plus.... I need to datalog a long pull in third to get my WOT mixture right, then maybe a couple more to get the timing perfect.

I'd set the rev limiter to 6600 Jim -- then shift it down around 6000-6200.

What he says^

Mine is set to cut fuel at 6500 (Rev limiter High RPM) and then add fuel back in once the RPM gets below 6000 (Rev limiter Low RPM), that's what the two numbers are for in the C950 software under Engine Parameters. My tranny shifts at 5900-6000 so the only time that I should see 6500 is when the tranny doesn't shift...and I've hit it three times, stupid non shifting tranny LOL!

Since I got the EFI system running pretty good a couple weeks ago, I been wondering why, whenever I get on it, it starts spitting and popping just when it's really feeling good.

While I was driving it today, it dawned on me...

The first stage of the rev limiter (random spark cutoof) is set at 5500...:o

I'll need to change that. Things happen REAL FAST in first gear this year, makes it hard to think.

EVERY man is allowed 1 ding-dong a week Jim. Just ask my wife.

He, He!!

pdq67

Mine is set to cut fuel at 6500 (Rev limiter High RPM) and then add fuel back in once the RPM gets below 6000 (Rev limiter Low RPM), that's what the two numbers are for in the C950 software under Engine Parameters.
AHHHH, is that what they are?

ok, cool. High is now set for 7000, low for 6700. Can't wait to take her for another "spin"!

Let us know how she runs!!

pdq67

Get that new combo to the track!

Jim I'd set your high side cut out at 6600 and your low side 6300 and shift at 6000. 7000 on an oops once in awhile is one thing, but that is pushing you bottom end a little more than I would take it on a regular basis.

Leaned on her "a lil bit" yesterday.

My popping and spitting is now at 6200. Rev limiter is at 7k.

Weird.

I've done zero tuning at WOT yet. I need either a copilot or a good short datalog, I'll get one or the other today. I have no idea where my mixture is above about 4000 rpm.

The only other change I made was to reduce the fuel pressure to try to get some pulsewidth at idle and cruise. The affect of that change is to lean the mixture perhaps 20% everywhere.

I'll do more tinkering today.

Jim, if you can, use an ipod or mp3 player that has recording function and record a short drive around town, rev it up, turn the tires in your driveway and mess with a sound clip for us to hear :thumbsup: