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Old Jan 30, 2014 | 07:06 AM
  #39376  
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Year: 1988
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Originally Posted by NewKindOfClown
Poly, yes. Rubber shouldn't be a noticeable increase.


Correct, and they make that clear. Specs are on the site.


I have no issues with mine except an increase in vibes in the seat and steering wheel. Don't notice it over the vibes from when the two 12s hit, so I don't really care.
I put in energy suspension mounts when I did my cam swap and intake upgrade, no complaints, and those mounts are beasts, but my engine is very smooth.
Old Jan 30, 2014 | 07:08 AM
  #39377  
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Originally Posted by n91chriss
I put in energy suspension mounts when I did my cam swap and intake upgrade, no complaints, and those mounts are beasts, but my engine is very smooth.
I take that back,I did have to grind the sleeve until it would go in, but once I gave it .01-.015 and torqued the ever living dog out of it it shouldn't come apart.
Old Jan 30, 2014 | 07:11 AM
  #39378  
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Originally Posted by n91chriss
I take that back,I did have to grind the sleeve until it would go in, but once I gave it .01-.015 and torqued the ever living dog out of it it shouldn't come apart.
I really should tell them that, they were way too long, something like .05-.075 too long to go into my engine bracket, luckily I checked before trying to drop the engine in.
Old Jan 30, 2014 | 12:14 PM
  #39379  
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Is there any aftermarket throttle bodies for the 4.0?

Bigger bore, bigger butterfly. Etc.
Old Jan 30, 2014 | 02:01 PM
  #39380  
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Of course there is. IiRC 62mm or 65mm is the largest bored you can fit. There was a user here selling 60mm bored ones. Works awesome.
Old Jan 30, 2014 | 02:08 PM
  #39381  
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Originally Posted by sycoglitch
Of course there is. IiRC 62mm or 65mm is the largest bored you can fit. There was a user here selling 60mm bored ones. Works awesome.
Yeah. If I recall, he only bore out the portion from the butterfly to bottom, doesn't really do anything because the top portion is still the same diameter.

If the bore from top to bottom was larger, along with a larger butterfly, that would be a real improvement.
Old Jan 30, 2014 | 02:26 PM
  #39382  
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1988 XJ NP231

I know I've got a vac leak for the CAD front axle disconnect.

But I wanted to see if the transfer case would still engage and even when dropped to 4low it didn't change anything gear wise. I could drive 30-40 with no high revs or anything.

In my old 90 np242 I would barely be able to go 10-20mph in 4low.

Would the vac leak affect the 4low for the rear axle or is my linkage need adjusting or something.
Old Jan 30, 2014 | 02:29 PM
  #39383  
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Originally Posted by DESERTXJ206
1988 XJ NP231

I know I've got a vac leak for the CAD front axle disconnect.

But I wanted to see if the transfer case would still engage and even when dropped to 4low it didn't change anything gear wise. I could drive 30-40 with no high revs or anything.

In my old 90 np242 I would barely be able to go 10-20mph in 4low.

Would the vac leak affect the 4low for the rear axle or is my linkage need adjusting or something.
Yes. It uses the vacuum to engage
Old Jan 30, 2014 | 02:31 PM
  #39384  
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Originally Posted by XJwonders

Yeah. If I recall, he only bore out the portion from the butterfly to bottom, doesn't really do anything because the top portion is still the same diameter.

If the bore from top to bottom was larger, along with a larger butterfly, that would be a real improvement.
He bored it so it the same diameter all throughout. Anything larger a new butterfly is needed. His works and does good for what it is but its true, a 65mm would make more of a difference
Old Jan 30, 2014 | 02:39 PM
  #39385  
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Originally Posted by sycoglitch
He bored it so it the same diameter all throughout. Anything larger a new butterfly is needed. His works and does good for what it is but its true, a 65mm would make more of a difference
Really. I have read his work on a thread here and he said he only bored out the bottom portion and left the butterfly alone

But anyhow I was reading about using a ford mustang's throttle body swap, seems interesting.
Old Jan 30, 2014 | 02:53 PM
  #39386  
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He bores out the bottom so the full diameter is actually used. It can only flow as much air as the narrowest point. The bore to match is an improvement, though not as good as a wider bore with a new valve.

A 62mm+ requires an exhaust upgrade to gain anything, though.
Old Jan 30, 2014 | 02:58 PM
  #39387  
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Originally Posted by NewKindOfClown
He bores out the bottom so the full diameter is actually used. It can only flow as much air as the narrowest point. The bore to match is an improvement, though not as good as a wider bore with a new valve. A 62mm+ requires an exhaust upgrade to gain anything, though.
Yeah. I am gonna do 2.5 exhaust soon, and the mustang TB are 65 mm stock. Sound like a fun project doing it
Old Jan 30, 2014 | 03:39 PM
  #39388  
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Originally Posted by XJwonders
Is there any aftermarket throttle bodies for the 4.0?

Bigger bore, bigger butterfly. Etc.
Here's the real one with a new butterfly:

www.strokedjeep.com
Old Jan 30, 2014 | 04:56 PM
  #39389  
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Originally Posted by sycoglitch

Yes. It uses the vacuum to engage
to engage the transfer case or the axle. I know it engages the axle but I thought the transfer case was lever engaged.
Old Jan 30, 2014 | 06:10 PM
  #39390  
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OK.. . Exhaust has sooty look to it and I am burning through gas like you would not believe. Any suggestions?



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