Author Topic: FtIbs?  (Read 10276 times)

Offline Zac.richardson1

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FtIbs?
« on: November 10, 2016, 08:24:59 pm »
really basic question but i didn't know the answer. for my 1/2ton truck with 35 inch tires(soon 38s) what is an impressive amount of ftibs? I'm looking to build a motor and i understand that horsepower isn't a big deal for my truck because of the gearing (3.08) but i want my truck to getup and go. basically I'm looking for a fast take off and to be able to do i mean burnout. what amount of ftibs should my truck have to be able to do so and how much money would this motor cost? any suggestions on where to start? Thanks

Offline Captain Swampy

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Re: FtIbs?
« Reply #1 on: November 11, 2016, 10:01:52 am »
Change your gears! Do you have a 700R4 or a TH350 transmission? or a manual tranny? Bigger tires hurt your take off, maybe keep the 35's
1987  350TBI 700R4  4X4  4.56 gears  33" BFG All Terrain


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Offline gunrac

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Re: FtIbs?
« Reply #2 on: November 11, 2016, 10:08:18 am »
basically I'm looking for a fast take off and to be able to do i mean burnout. what amount of ftibs should my truck have to be able to do so and how much money would this motor cost? any suggestions on where to start? Thanks

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Online VileZambonie

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Re: FtIbs?
« Reply #3 on: November 11, 2016, 10:34:18 am »
Agreed, 3.73:1 at least if you want to be able to achieve your desired results.
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Offline Stewart G Griffin

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Re: FtIbs?
« Reply #4 on: November 11, 2016, 03:40:24 pm »
i don't know;  For a street driven vehicle i'd say 400ft/lbs or more?   And really maybe it's not so much how much but how low rpm-wise it happens?

Offline Irish_Alley

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Re: FtIbs?
« Reply #5 on: November 11, 2016, 04:51:10 pm »
get up and go + 38s on ½ ton axles i dont see them lasting too long. go for ¾ton axles (14 bolt full floater) with the ratio like they said or 4.10.
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Offline Zac.richardson1

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Re: FtIbs?
« Reply #6 on: November 11, 2016, 05:30:31 pm »
700r4 tranny and its an automatic. planning on going to 3/4 ton axles soon but was wondering where should i buy? online? whats the procedure on changing the gearing? would a professional have to do it or..? also what is the pros and cons of the different gears(3.08, 4.10, 3.73, etc.) and what should i get for my truck with soon to be 38s? i'm hoping to eventually convert to a 4spd as well
« Last Edit: November 11, 2016, 05:38:15 pm by Zac.richardson1 »

Offline Irish_Alley

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Re: FtIbs?
« Reply #7 on: November 11, 2016, 06:02:14 pm »
the 700r4 wont hold up for long imo unless its been build for it with some power and those tires. i would go to a junkyard get the axles then get rims and tires as they should be 16" you can fit 15" rims but takes a little grinding
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Offline Zac.richardson1

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Re: FtIbs?
« Reply #8 on: November 12, 2016, 06:23:00 am »
So what transmission should I look for? This would also be a good time to convert it to a 4spd wouldn't it? What all do I need for that?

Offline hatzie

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Re: FtIbs?
« Reply #9 on: November 12, 2016, 11:11:49 am »
1/2 ton axles with 3.08:1 gears are not going to like 38" tires.  Burnouts will kill the axles even with 31" tires.
3.73 or even 4.11 rear gears.
Burnouts will kill a TH700R4 pretty quick.  If you want to have a chance of the trans lasting through a fair amount of abuse get a TH400.
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Offline Captain Swampy

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Re: FtIbs?
« Reply #10 on: November 12, 2016, 12:46:33 pm »
So what are your plans for this truck? Is it a toy or daily driver? What are the speed limits where you drive it? My daughter's pick up Bedazzled has a 700R4 with 4.56 gears on 33's. It mostly runs on 55 mph roads. It doesn't have a tach, but it works really well. I'd guess you might want to put 35's on it if running 70 mph. If it's a daily driver, you'll want a transmission with overdrive. Check PATC for upgrades to your current tranny. I don't think the 700R4's are weak and they have a lower 1st gear. You'll have to pick a transmission and then match gears and tire size according to it's intended use.
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Offline Zac.richardson1

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Re: FtIbs?
« Reply #11 on: November 12, 2016, 03:25:36 pm »
Speed limits around here are 55. It is a daily driver

Offline Irish_Alley

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Re: FtIbs?
« Reply #12 on: November 12, 2016, 03:28:48 pm »
th400 4.10 and 38s sound nice if you stay under 60 you could get 10 mpgs. i got 10 with a sm465 and that setup driving easy. if i drove it like a kid i would get 7
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Offline Zac.richardson1

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Re: FtIbs?
« Reply #13 on: November 12, 2016, 10:39:18 pm »
ok thanks, one more question. whats the difference between the 3.08 gear and the 4.10

Online VileZambonie

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Re: FtIbs?
« Reply #14 on: November 13, 2016, 07:26:05 am »
1.02  8)
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              ⌠¯¯¯¯¯'   [☼===☼]
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