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Discussion Starter #1
Well, I took the time to readthrough the tire and lift sticky and I'm a bit curious. I read where it said that generally you'd want to go with a 35" tire with a 6" suspension lift. However, I've seen several reader's rides on here that exceeded that tire size with 6" of lift. I'm definetely interested in Rough Country's 6" suspension kit for my truck (on a bit of a budget) and I had planned on going with a 38x12.50x15 tire. I currently have 33x12.50x15 Gillette Kodiak A/T's and experience no rub with bumper or anything whatsoever. I'd prefer to run a bigger tire than a 35" if possible, preferably a 38" as mentioned. Is this obtainable? Will I have to downsize to a 37, 36, or SETTLE for a 35?

Being that my truck is an '89 XLT with the speed density 5.0, I'm assuming most aftermarket work you would try to do to the motor would mess with the computer a bit? Have any of you modified your engines i.e camshafts, heads, intake porting, throttle bodies, aftermarket pistons, etc, without it screwing with the computer?? I've seen mass air conversion kits available, but I'm not sure it's worth spending all that money for it. I'd like to add at least some pep to the fuel injected 5.0 that I have without having to go the carbed route, but I reckon that's plan B, worst case scenario. Please, any info regarding both topics will help. Thanks.

Ryan
 

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Argh... jesus...

SEARCH.

Like the 18th thread just in the past week featuring all the same questions, that were just answered, and have been answered hundreds of times already.

1) People put bigger then 6" of lift on their TTB/stock axles. Is it smart. NO. 6" of lift will clear 35's easily, and with wheeling, that's really the biggest size tire you should put on 1/2 ton axles.

Settle for whatever you want, and break whatever you want.

Stock EECIV SD is fairly lenient. It doesn't like cam LSA's of <114 degrees, and it doesn't like BIG displacement changes, especially something that would warrant bigger injectors.

RLKBOB built a worked 357 that ran fine on stock SD.


Search, search, and oh, please search. This has all be said so many times that it's not even funny.
 

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i just put a 4" lift with 36s and i love how it looks with the fenders a little stuffed and i dont have any rubbing just the right rims so i bet you could get away with 38s and with a 6" just the fenders would be stuffed
 

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i just put a 4" lift with 36s and i love how it looks with the fenders a little stuffed and i dont have any rubbing just the right rims so i bet you could get away with 38s and with a 6" just the fenders would be stuffed
Do you have a pic of your wheels?
I am running 6" with 36's on 15x10 3.75 BS and I have to trim front and rear of the rear fender wells, and the rear of the front fender well to keep huge chunks of tire from getting ripped off...:banghead
 

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Discussion Starter #5
My apologies for the crime of not searching thoroughly enough to acheive my exact answers I was looking for. As far as going more than a 35" tire on a 6" lift and snapping the 1/2 ton axles, I seriously doubt I'm going to drive the truck that hard to generate that much of a problem, but I reckon with having the bigger tires and the added weight strain, it could happen. I'm hoping everything works out to where I can indeed do the 6" lift and 38x12.50's without a problem, being that the 38's are obtainable for FREE from a friend, but if I have to go with a 37, or 36, I'll just step the aggressiveness in the tire up more than I had planned.

As far as the EECIV SD beng lenient, sounds like I might be doing some tinkering with it. I have a .030 block handy with some 11.1 dome pistons. Might try that and a low-end torque camshaft along with some cobra gt40 irons I have lying around and see what happens.
 

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that motor setup wont run for poop with the stock efi. not to mention you would need premium at least to run it. get the compresion ratio down to 9.5-1 and get a cam with a lob seperation of 114+ or have a custom cam made which might be the better route because it would be tailored to your engine setup.
 

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this is mine with leveling coils and new body mounts and 1.5 body lift with 37x12.5r15lt goodyear mtrs on 10" rims with some fender trimming

this is it with all the above with 6" approx. aand all the above

I ran 4:11 with the cd trans I would go with the 4:56 for 35 or 4:88 for the 37 with the overdrive trans
 

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aka: kemicalburns
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with my e4od,35" tires and 4.88 gears at 65mph i am at 2200rpms
 

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that motor setup wont run for poop with the stock efi. not to mention you would need premium at least to run it. get the compresion ratio down to 9.5-1 and get a cam with a lob seperation of 114+ or have a custom cam made which might be the better route because it would be tailored to your engine setup.
Why wouldn't his motor run fine? The EEC won't have a problem with the heads, and just as long as he keeps his LSA at 114, and only goes .30 over, it shouldn't make a difference.
 

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I've got the 6" RC kit, and I put 36"s on it. Like most of the people mentioned. I wouldn't recommend pushing it past 36 with stock axles, unless its a DD. I had to trim my bumper a little to avoid rubbing on flex.
 

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aka: kemicalburns
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Why wouldn't his motor run fine? The EEC won't have a problem with the heads, and just as long as he keeps his LSA at 114, and only goes .30 over, it shouldn't make a difference.
I guess the vague description on which cam he would use, but that 11-1 comp ratio would have me a little conserned as well.
 

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Discussion Starter #12
Sorry I didn't explain myself a little more. Bronco4Life mentioned to stay with a camshaft with no <114 LSA and automatically a few already come to mind that will work properly with what I want to do. As far as the 11.1 comp ratio, I should have explained that a little more too. The dome pistons I have are 11.1 using a 58cc cylinder head. Bolting the cobra GT40 irons on top of them would drop the comp ratio down around 10.5:1 or lower, and if need be, I can always go with slightly thicker head gaskets to bring that number down a smidgen more if I have to.
 

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aka: kemicalburns
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im following ya know. the cam selection is the most important part
 
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