3.36 diff swap to 3.70...How will it feel?
Heel & Toe
Joined: Sep 2011
Posts: 18
Likes: 0
From: Amarillo Texas
I guess I don't understand...Do you need a new differential housing and/or posi carrier & side yokes? Because $800 for gears and a rebuild kit is too much. US Gears (made in Chicago!) from Tom's are $270 for a 3.73 ring and pinion, and a rebuild kit with Timkin bearings & seals shouldn't cost more than $150 or so. Are you sure they didn't mean $800 all-in?
I am a big fan of the 3.73s but I went from a 3.08 so I could really feel the difference
I am a big fan of the 3.73s but I went from a 3.08 so I could really feel the difference
Thread Starter
Intermediate
Joined: Sep 2007
Posts: 49
Likes: 1
Thank you guys, as always.
To clarify.....The price of eight hundred bux I quoted was for a fully rebuilt diffential with my choice of new gear ratio, and the labor to take out the old diff and install the new diff is between three to five hundred bux.
The info on the fully opening of the secondaries is terrific, and the distrib curve/timing great. Hope everyone else is making notes like I am.
I bought the car with true duals and no cats, so that's an improvement over the OEM setup, and apparently adding headers won't add much HP on this lower HP engine, or so I've been told in this thread.
I am running stock mufflers....think getting rid of them or changing them will add much power?
To clarify.....The price of eight hundred bux I quoted was for a fully rebuilt diffential with my choice of new gear ratio, and the labor to take out the old diff and install the new diff is between three to five hundred bux.
The info on the fully opening of the secondaries is terrific, and the distrib curve/timing great. Hope everyone else is making notes like I am.
I bought the car with true duals and no cats, so that's an improvement over the OEM setup, and apparently adding headers won't add much HP on this lower HP engine, or so I've been told in this thread.
I am running stock mufflers....think getting rid of them or changing them will add much power?
Burning Brakes
Joined: Sep 2008
Posts: 805
Likes: 5
From: Naperville Illinois
Is your current rearend shot? If it isn't and you have that kind of money to spend, I'd do heads & intake(and a cam, if you can afford it). There are good heads available for under a grand, and great heads for $1,400 - $1,500. Maybe somebody that's done it can recommend a good combo based on your price range...
Based on your posts so far, seems like you want some performance, and for the money I think you'll be happier with better heads and a 3.36 than you would with your current motor and a 3.70 rear
Just my 2c
Based on your posts so far, seems like you want some performance, and for the money I think you'll be happier with better heads and a 3.36 than you would with your current motor and a 3.70 rear
Just my 2c
Race Director
Joined: Apr 2000
Posts: 17,665
Likes: 194
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
Mod the motor first then select your gears.
Only thing youll notice at this point is a slightly different cruise rpm.
For the money spend think youll be disappointed.
Noticed very little diff going from 3.08 to 3.73 Accel felt a little better (wasnt happy) noticed cruise rpm meaning taching out on the fwy. Week later went to 4.11 and an OD trans....perfect!!
A hotter motor will love more gear and will then feel the part.
Only thing youll notice at this point is a slightly different cruise rpm.
For the money spend think youll be disappointed.
Noticed very little diff going from 3.08 to 3.73 Accel felt a little better (wasnt happy) noticed cruise rpm meaning taching out on the fwy. Week later went to 4.11 and an OD trans....perfect!!
A hotter motor will love more gear and will then feel the part.
Safety Car
Joined: Sep 2007
Posts: 4,451
Likes: 326
From: Indy Indiana
just understand that when they get your rear end dropped, they will find that you need all new ujoints, rear crossmember bushings, heavy duty rear end cover. plus a significant number of posi carriers have a crack in them ( killing your core refund). they will also have to cut your exhaust and reweld it back. they are going to want to put in new side yokes, your old yokes will be worn down to the C-clips. al of which usually are not included in the estimate. plus a rear allignment after all the work is done. a 30 year old car.. some bolts are going to break..
you will find that your 1300$ total may easilly get in 2000+.
you will also find that if you choose a 4.11 or a 4.56 that the car is basically undriveable on the street. you will not even use 1st gear, it will be such a granny gear.
all for a 'tired' 350. My advice is to rethink the direction of your money.
just my opinion of course..
you will find that your 1300$ total may easilly get in 2000+.
you will also find that if you choose a 4.11 or a 4.56 that the car is basically undriveable on the street. you will not even use 1st gear, it will be such a granny gear.
all for a 'tired' 350. My advice is to rethink the direction of your money.
just my opinion of course..
Racer
Joined: Jul 2007
Posts: 458
Likes: 55
From: Southeast Ohio
you will also find that if you choose a 4.11 or a 4.56 that the car is basically undriveable on the street. you will not even use 1st gear, it will be such a granny gear.
I've not found mine to be undriveable.
I personally find the car much more fun to drive with lower gears.
But mine is all in town driving.
I've not found mine to be undriveable.
I personally find the car much more fun to drive with lower gears.
But mine is all in town driving.
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Burning Brakes
Joined: Feb 2011
Posts: 849
Likes: 0
From: Woodland California
60102 Lunati cam kit $250
Summit headers 125
Edelbrock manifold 125
Edel. cam chain set 125
Summit rebuild kit 150
dual exhaust 200
It's a lot of work but it will transform you motor.
This is what I did.
A friend and I did this in a week,
Didn't pull the engine, rolled in the new bearings.
My 75 had 90,000 miles on it and there was no ridge in the cylinder.
I simply honed the cylinders and re-ringed the engine.
I did put on new heads, but you could clean up yours.
lap the valves and new valve seals and you would be good to go.
This is labor incentive but the most bang for the buck.
The ZZ4 heads were $650.00 for the set.
Ralph
Summit headers 125
Edelbrock manifold 125
Edel. cam chain set 125
Summit rebuild kit 150
dual exhaust 200
It's a lot of work but it will transform you motor.
This is what I did.
A friend and I did this in a week,
Didn't pull the engine, rolled in the new bearings.
My 75 had 90,000 miles on it and there was no ridge in the cylinder.
I simply honed the cylinders and re-ringed the engine.
I did put on new heads, but you could clean up yours.
lap the valves and new valve seals and you would be good to go.
This is labor incentive but the most bang for the buck.
The ZZ4 heads were $650.00 for the set.
Ralph
Melting Slicks
Joined: Mar 2002
Posts: 2,164
Likes: 7
From: Beringen
It will give better acceleration but unless your engine has got the powerband associated with a shorter rear axle, it's not as good as it might seem.
I do not agree upon the fact that a gear change doesn't improve acceleration as it does. You basically have got more torque at the rear wheels.
I do not agree upon the fact that a gear change doesn't improve acceleration as it does. You basically have got more torque at the rear wheels.
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
Since you're getting some tune up advice, here's a little more. As for the carb, would even check a bit further. The secondary upper air valve can sometimes hang up if the upper housing plate was torqued down to much. Also check the enrichment power piston movement. Also good to pull the dizzy for inspection, as the centrifugal advance shaft can get gummed up. With 80k mi on the clock, think I'd have the whole thing refreshed, or go crate. The 3.36's will be fine.
