poor choice on rear
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From: Newburgh in
poor choice on rear
had 2.73's in my 74 l48 when i got it and a friend had a complete rear out of a 69 427 car with 4.56's for $100.Make a long story short i bought this paid to have it installed and now wish to god i wouldn't have. So i will be selling this OR looking for someone who is interested in a trade i would rather have 3.23/3.55 even 3.73 damn 4.56 just to much with a th400.
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From: Newburgh in
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Hey but it's a LOT of fun away from the redlights right? You don't need new gears...you just need more motor that likes 7000 rpm!!
JIM
JIM
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From: Newburgh in
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From: Newburgh in
got a pretty stout zz4 420hp problem is it has only 300miles and i was told to baby it and i dont think turing these high rpms are good for break in so i cant really go over 35 for next 200 or so miles that is gonna really suck.....
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That thing was broken in about 5 minutes after you cranked it. No different than throwing a new motor on the dyno. It's either right or it's not.
I ran 4.56's in my old Camaro with a 427 and both a T-400 w/4500 converter and a 4 speed. Pretty much lived at 4000-4500 rpm all the time...but it never hurt it. I still have the motor after 20+ years!
Just depends on how much highway driving you do and how annoying it is.
What did you do to the zz4 to get the 420 HP?
If the planets are all aligned properly 420Hp *can* get you high 11's@117 mph or so hauling 3300 lbs. 117 MPH with a 4.56 gear and a 28" tire is going to take a little over 7000 RPM at the line if I guesstimate the converter slips 8% or so maybe?
But since we're talking a real street car here with accessories, exhaust etc, you won't likely get that much MPH ...so the peak RPM will be a lot lower too. But it's going to need to be happy to 6500 rpm for sure.
JIM
I ran 4.56's in my old Camaro with a 427 and both a T-400 w/4500 converter and a 4 speed. Pretty much lived at 4000-4500 rpm all the time...but it never hurt it. I still have the motor after 20+ years!
Just depends on how much highway driving you do and how annoying it is.
What did you do to the zz4 to get the 420 HP?
If the planets are all aligned properly 420Hp *can* get you high 11's@117 mph or so hauling 3300 lbs. 117 MPH with a 4.56 gear and a 28" tire is going to take a little over 7000 RPM at the line if I guesstimate the converter slips 8% or so maybe?
But since we're talking a real street car here with accessories, exhaust etc, you won't likely get that much MPH ...so the peak RPM will be a lot lower too. But it's going to need to be happy to 6500 rpm for sure.
JIM
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From: Irving Texas
I have the same dilema, 4.56 gears in my 69 Camaro. I use it for drag racing only since driving the freeways at 5000 rpm isnt too much fun.
I'm using a TH350 trans.........whats the consensus: 3.73s or 3.55s? With an engine that doesnt go over 5000 rpms.
I'm using a TH350 trans.........whats the consensus: 3.73s or 3.55s? With an engine that doesnt go over 5000 rpms.
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5000???? Wow.....well....3.36's will only get about 119 mph at 5000 rpm *if* the converter doesn't slip at all and you have 27" tires.
3.73's will top out at about 108 mph at 5000 rpm.
3.55's will get about 113 mph@5000.
So since I'm assuming we don't have some monster twin turbo big HP motor we're dealing with...I'd lean to the 3.36-3.55 range at the most unless you just want to have some fun around town power...then the 3.73's would help the seat of the pants a lot.
JIM
3.73's will top out at about 108 mph at 5000 rpm.
3.55's will get about 113 mph@5000.
So since I'm assuming we don't have some monster twin turbo big HP motor we're dealing with...I'd lean to the 3.36-3.55 range at the most unless you just want to have some fun around town power...then the 3.73's would help the seat of the pants a lot.
JIM
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From: Livonia MI
Yea, 4.56 is way to much gear for the street, and probably just grab "redvetteracer's" 3:36 assembly and call it a day, as even 3:73's are a bit much unless going with an o.d. tranny. Guess you could do your own gear change, but not cheap, lot's of precision set up work, and probably end up with the wrong pinion angle anyway.
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From: Livonia MI
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From: Newburgh in
Yes i defiantly would like to trade that will be perfect for me....Dont suppose you live close to southern indiana do you? i would rather pay you a few hundred to come down and swap then pay a shop to remove/replace but i can if i need too. I am well aware of my ability and i know this is not something i care to try.