had some fun yesterday but
Thread Starter
Racer
Joined: Nov 2007
Posts: 350
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From: coon rapids mn
had some fun yesterday but
went grove creek raceway here in mn 1/8mile track. and ran the vette had a lot of fun but not so happy with the vette. I just recently swap the turbo 400 for a m21 Muncie I have 3.73 gears in the rear. the problem is I just could not get it out of the hole the sixty foot was horrible but came alive after that the best it would do is and 8.8 at 83mph and a 2.1 sixty foot the reason for the disappointment is with the th400 it ran and 8.5 at 80mph with a 1.88 sixty foot. so it mph better with the 4 speed but e.t. slower is this what to expect or do I have something off with the tune it would not come to life until the rpms got up
Thread Starter
Racer
Joined: Nov 2007
Posts: 350
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From: coon rapids mn
it's a holley 3310 750 and the distributer is a zz4 unit with a msd module. I don't know the exact curve but its all in at 3000 I want to say 16 initial and 36 at 3000. the car hooked ok did have some wheel spin but when it hooked it bog for a second. I tried leaving really easy just off idle all the way to 5000. It almost seem like not enough of a pump shot being a vac secondary carb
Race Director
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From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
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You gave up a ton of first gear multiplication with the M21. It's got a 2.20 first vs the T-400 with a 2.48 plus a converter that will keep the RPM up higher.
It's going to take some high RPM launches and/or some clutch slipping to get the 60's back.
Keep at it...the 4 speed is a lot more cool and fun than the T-400 willever be!
JIM
It's going to take some high RPM launches and/or some clutch slipping to get the 60's back.
Keep at it...the 4 speed is a lot more cool and fun than the T-400 willever be!
JIM
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Thread Starter
Racer
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
You gave up a ton of first gear multiplication with the M21. It's got a 2.20 first vs the T-400 with a 2.48 plus a converter that will keep the RPM up higher.
It's going to take some high RPM launches and/or some clutch slipping to get the 60's back.
Keep at it...the 4 speed is a lot more cool and fun than the T-400 willever be!
JIM
It's going to take some high RPM launches and/or some clutch slipping to get the 60's back.
Keep at it...the 4 speed is a lot more cool and fun than the T-400 willever be!
JIM
Racer
Joined: Feb 2013
Posts: 386
Likes: 3
From: Clifton Virginia
Did you run with drag radials or regular tires? Drag radials will definitely help on the launch with little heat on them.
