Help! Gained 9tenths and lost 6MPH! Any help please.
Thread Starter
12 Second Club
iTrader: (10)
Joined: Jul 2005
Posts: 477
Likes: 0
From: MONTGOMERY,AL
Help! Gained 9tenths and lost 6MPH! Any help please. Tonight i ran at the track and ran 13.3s @ 106.18 Mph w/ 2.108 60'. The car was running 12.48 @ 112.27 w/ 2.089 60'. The only things i've changed between the runs was a Strange dana 60 with true trak and 3.73s vs. stock 10 bolt w/4.10s , mild steel driveshaft vs. stock alum. and I had the t56 trans with a rebuild by Joe and Amber @ t56 rebuilds. No other changes. And I noticed the stock tach and speedo started jumping back and forth during the shifts (only at the track, not on the street). The only thing i can think of is the clutch slipping. But the clutch feels like it is grabing really good (spec stage II). Not sure what is going on. Any help please!
less gear, more rotating weight, and a worse 60'. the dana 60 is a beast of a rear end, and it will cause a lot more drivetrain loss, espcially compared to a 10 bolt with 4.10's. since you have a d60, and you have dr's ... your 60' is killing you. 1.6-1.7 should be obtainable with a good launch, even with mild suspension mods. practice that launch, and i would think of a way to get a little more power to the wheels ... nitrous should do the trick.
i wouldnt think the added weight would lose you that much, but i guess more weight+bad day at track could equall that much. i mean you can go to the track on different days with the same stuff and run a tenth or 2 different
Rotating weight hurts worse than dead weight.
IMO the Dana 60 is just silliness that is the rear all the guys with big mud and rock crawling trucks want. absolutely foolish to put one in a car like this and here you can see the results. I do think weather is a part but that axle is just too big.
The b-bodies have VERY few problems with the 8.5" 10 bolt despite all our extra weight, our 30 spline unit is comparable to the 12 bolts of old. For a street f-body that needs an axle upgrade I think the 12 bolt a good choice because I know it is available the 30 spline 10 bolt 8.5 would do if someone built it. On a race car an 9" will do the trick. Leave the Dana 60 to the off roaders.
This is the same "more is better" mentality so many of you apply to the cams and it is working just as "well".
IMO the Dana 60 is just silliness that is the rear all the guys with big mud and rock crawling trucks want. absolutely foolish to put one in a car like this and here you can see the results. I do think weather is a part but that axle is just too big.
The b-bodies have VERY few problems with the 8.5" 10 bolt despite all our extra weight, our 30 spline unit is comparable to the 12 bolts of old. For a street f-body that needs an axle upgrade I think the 12 bolt a good choice because I know it is available the 30 spline 10 bolt 8.5 would do if someone built it. On a race car an 9" will do the trick. Leave the Dana 60 to the off roaders.
This is the same "more is better" mentality so many of you apply to the cams and it is working just as "well".
my lil brother went to the track with a taller tire last night and lost .5 seconds and 2-3 miles per hour. just from the tire being taller. that again goes back to more rotating mass. i suppose that really hurts ETs. he went from a 26' to a 28'.
Trending Topics
Originally Posted by LT1Falcon
i wouldnt think the added weight would lose you that much,
I once lent a TH-350 to an LS1 buddy of mine. He swapped out his race prepped TH-350 for mine and gained over a tenth (and it wasn't even my best TH-350).
The steel driveshaft is also a great way to rob power.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Originally Posted by Burning Rubber
my lil brother went to the track with a taller tire last night and lost .5 seconds and 2-3 miles per hour. just from the tire being taller. that again goes back to more rotating mass. i suppose that really hurts ETs. he went from a 26' to a 28'.
I think the Dana 60 is a bit much for a street/drag F-body. Like with mine I really want to put a 12-bolt in it and the hubby thinks I should go for the 9-inch. Honeslty my car is a street/drag car so I don't see the point in a 9-inch. I'm sorry you lost so much on your ET's Eric, maybe you can swop it and find a good deal on a 12-bolt. Maybe up the gears back to 4.10's, Clint kept his in the 9-inch I think they are 4.11's. He lost some with the 9-inch but I guess we'll never really know how much until he returns to the track for some good ET's.
That's the price you pay for your **** to hold together. I'd run a 10 bolt and aluminum d/s if I could. Too bad I already busted an aluminum shaft and not willing to chance the 10 bolt. One thing about it, you're all set for a big *** motor! Instead of worrying about what you lost, build a hellatious motor and put that big stuff to work.