Author Topic: changing gears  (Read 8211 times)

Offline str8bloc

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changing gears
« on: December 22, 2010, 11:17:51 pm »
i have 3.08s right now thinking 3.73 or 4.11 what do u think itll be street/strip with a th350 and a 383
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Offline acefoxx

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Re: changing gears
« Reply #1 on: December 22, 2010, 11:30:29 pm »
I have 3.73 in mine with a th350. My rear end is a 14 bolt with posi out of a 91 454SS. I couldn't imagine trying to drive it on the street with any shorter of a gear like 4.11s or what not. I got real good 60 ft times with them. Here are my best time slips.
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Offline ohio hab

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Re: changing gears
« Reply #2 on: December 23, 2010, 11:30:32 am »
I have 3.73's in my rear axle assembly. You can also run with the 4.11's depending on what size your tire height is, with good results and decent street driveability.

Online Captkaos

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Re: changing gears
« Reply #3 on: December 23, 2010, 12:05:03 pm »
3.73 with a TH350 and a 2WD truck with less than 30" tires it going to be on the ragged edge of sanity.  I found 3.42's are the best ratio in that situation.

Offline Stewart G Griffin

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Re: changing gears
« Reply #4 on: December 23, 2010, 01:23:35 pm »
Too many unknowns to tell.  i would test with the 3.08's, if there's wheelspin work on solving that first.

Offline bobcooter

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Re: changing gears
« Reply #5 on: December 23, 2010, 02:30:59 pm »
4.11's will be way more "strip" than "street".
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Offline str8bloc

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Re: changing gears
« Reply #6 on: December 23, 2010, 09:14:01 pm »
well the most straight line i drive is like 2 miles. the 308s are way to sluggish for me i want more umph. the street tires im using are 235 75 15 and the dots are 325 50 15
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Offline str8bloc

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Re: changing gears
« Reply #7 on: December 23, 2010, 10:59:02 pm »
was it a straight bolt in for the ss rear end?
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Offline acefoxx

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Re: changing gears
« Reply #8 on: December 23, 2010, 11:39:12 pm »
Nah, I just cut the pearches off and set the angel and welded on the new ones. The width was perfect though. I later switched to a coil over 4 link.
« Last Edit: December 24, 2010, 12:11:39 am by acefoxx »
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Offline lechez71

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Re: changing gears
« Reply #9 on: December 27, 2010, 09:55:49 pm »
since you dont do lots of driving on the highway, i say 4.11 but if you plan on driving it go 3.73. with the 4.11 and a 28" tire at 65mph your rpms would be around 3,300 that would suck for highway use. if it still slow off the line you need more HP. ;D what stall verter do you have?

Offline 1980c10

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Re: changing gears
« Reply #10 on: December 28, 2010, 11:02:23 pm »
I had 4.11 with a 30.5" tall tire, but I had overdrive and couldn't imagine driving it much without the extra gear. You could consider an overdrive trans if you're are feeling pretty serious about the 4.11.

Offline str8bloc

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Re: changing gears
« Reply #11 on: December 29, 2010, 08:47:52 pm »
how was it on the overdrive. monster transmission is about 1000 for the setup, but i wanna drop the tranny and the gears now. then build my stroker. overall i want a 450 hp 388,700r4 and 4.11 gears.with this setup i think itll be a bad street machine.
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Offline lechez71

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Re: changing gears
« Reply #12 on: December 29, 2010, 09:15:13 pm »
if you plan on the 700r4 go with 4.11. thats what im getting. i have a 4L60e tranny. youll have the extra gear so it wont be bad. i figured with 28" tire, 4.11s and the gearing of the 60e tranny at 65mph ill be spinning about 2200rpm.

Offline 1980c10

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Re: changing gears
« Reply #13 on: December 29, 2010, 10:25:05 pm »
if you plan on the 700r4 go with 4.11. thats what im getting. i have a 4L60e tranny. youll have the extra gear so it wont be bad. i figured with 28" tire, 4.11s and the gearing of the 60e tranny at 65mph ill be spinning about 2200rpm.

That sounds real close to what I had with the 4.11s and a 5 speed.

So why not build your engine and trans, drive it, see if it feels like you need a lot more?
That's my approach with my current project.

Offline str8bloc

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Re: changing gears
« Reply #14 on: December 30, 2010, 04:29:22 pm »
either way i think ima use my 3 speed with 4.11s for now
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