Need help with combination??????(406)
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Joined: Feb 2004
Posts: 74
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From: Dobson ,NC
Car: 87 IROC - Z
Engine: 406 smblk
Transmission: 4 speed manual
Need help with combination??????(406)
i ran a track time of 9.1 in the 1/8 with my 3.27 geared t56 iroc and was very upset. Just wanting some help with my new combination and what u think my power and difference in track times would be??? should i change cam or just 1.6 rollers
OLD 406,flattops,stock heads 993,luntai bracket master 230* .480 lift cam,1 5/8 heddman lt , true duals , rpm intake 750vs carb
NEW: dart pro 1 72cc 200cc runners, holley 750 dp, 1.6 roller rockers, victor jr?????
what kind of difference will this make in power???? what about at the track?????? THANKS
OLD 406,flattops,stock heads 993,luntai bracket master 230* .480 lift cam,1 5/8 heddman lt , true duals , rpm intake 750vs carb
NEW: dart pro 1 72cc 200cc runners, holley 750 dp, 1.6 roller rockers, victor jr?????
what kind of difference will this make in power???? what about at the track?????? THANKS
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Joined: Jul 2008
Posts: 751
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From: NE Ohio
Car: 82 Z28
Engine: TT LS
Transmission: 4L80E
Axle/Gears: S60 3.54's
Re: Need help with combination??????(406)
I'd be more concerned about the mph and 60 foot time. If that time is truely all your car can do, the mph I'd guess to be 75-77. I'm guessing your 60' time was something like 2.4 when it should be under 2.0 if not under 1.8.
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From: BUFFALO, NY
Car: '89 IROC-Z
Engine: 355
Transmission: 700r4 edge 3000 stall
Axle/Gears: 9-bolt 3.73
Re: Need help with combination??????(406)
keep the rpm intake its a good intake. Shave those 72cc heads down to raise the compression. Get some sticky tires. I think the heads/rockers/carb will make a big difference. Should get you in the 7s. I would put 4.10s in too
Thread Starter
Junior Member
Joined: Feb 2004
Posts: 74
Likes: 0
From: Dobson ,NC
Car: 87 IROC - Z
Engine: 406 smblk
Transmission: 4 speed manual
Re: Need help with combination??????(406)
can i maybe run a thin headgasket for comp. to be around 10.3 ? 7's is where i want to be THANKS PS i dont think 9 bolt will hold long with 4.10s hopefully i can swing a moser before long
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iTrader: (1)
Joined: Apr 2007
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From: BUFFALO, NY
Car: '89 IROC-Z
Engine: 355
Transmission: 700r4 edge 3000 stall
Axle/Gears: 9-bolt 3.73
Re: Need help with combination??????(406)
u can't even fit 4.10s in a 9 bolt u can get 3.70s though. I wouldn't get anything till the rear end blows up. My 9 bolts still holding up fine.
Thread Starter
Junior Member
Joined: Feb 2004
Posts: 74
Likes: 0
From: Dobson ,NC
Car: 87 IROC - Z
Engine: 406 smblk
Transmission: 4 speed manual
Re: Need help with combination??????(406)
btw my 60ft was 2.1 and 79mph
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i dont think i can get in 7s with 3.27 u??? I thought i seen 4.10s on 9bolt .com
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i dont think i can get in 7s with 3.27 u??? I thought i seen 4.10s on 9bolt .com
Last edited by 406iroc; Oct 12, 2008 at 09:06 PM. Reason: Automerged Doublepost
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Senior Member
iTrader: (1)
Joined: Jul 2008
Posts: 751
Likes: 2
From: NE Ohio
Car: 82 Z28
Engine: TT LS
Transmission: 4L80E
Axle/Gears: S60 3.54's
Re: Need help with combination??????(406)
That combination just sounds like it doesn't work together. I'd guess it needs a tune and better gear for the most part. I'd expect that motor to be capable of a low 8, and mid-upper 7's with the stuff you're looking to do. Granted I don't know all that much about the internals of your motor, but I'm thinking those heads should be okay. My guess is that you're looking at low 10's:1 compression.
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iTrader: (1)
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From: BUFFALO, NY
Car: '89 IROC-Z
Engine: 355
Transmission: 700r4 edge 3000 stall
Axle/Gears: 9-bolt 3.73
Re: Need help with combination??????(406)
the problem is his motor needs more compression for that cam. You want to shoot for 10:1. Also .480 lift is pretty puny, the 1.6rockers will raise it up to about ~.500. That and those heads flow great, the double pumper is gonna shave off time by itself. What tranny do you have? What tires are you running? He's right about the tune, make sure you got your total timing set and your carb set up right. I'd also work on my shift points/shifting and launching/driving. Take your air cleaner off too and try to shave any unnecesary weight.
I think he is perfectly capable of runnning 7s. I did 8.10 with a mild 355 vacuum secondary carb and 3.27 gears with 700r4 tranny (junk for drag racing). I could get into the 7s probably just driving it some more but a double pumper would get me there for sure.
I think he is perfectly capable of runnning 7s. I did 8.10 with a mild 355 vacuum secondary carb and 3.27 gears with 700r4 tranny (junk for drag racing). I could get into the 7s probably just driving it some more but a double pumper would get me there for sure.
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