Porting my CJ manifold with gt500 TB

herzeleid05

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I have a CJ manifold with a GT500 tb. Should I bother porting the manifold until I upgrade my TB or would it be a waste of time? I want to upgrade my TB but I'm waiting for a good deal on a used one to come around. Just not sure how much the TB is holding me back at this point. I've been told by a tuner that a TB upgrade is only worth about 5HP
 

jn2

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Get it ported if you plan on ever having it done, better to only do the install once then deal with down time when you do decide to port it.

I rocked the twin 60 for almost a year with no issues.
 

herzeleid05

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Get it ported if you plan on ever having it done, better to only do the install once then deal with down time when you do decide to port it.

I rocked the twin 60 for almost a year with no issues.


I've already had it on the car for about 6 months. I'm going to upgrade the TB eventually. Just wasn't sure I would reap any benefit with the twin 60 on there. May just wait until I find a really good deal on a TB and port it and add a new TB at the same time. Appreciate your input.
 

noldevin

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The twin 60 is choking that manifold, it should really have at least a twin 65. Ideally a twin 67. I'd do that first, or do them together. With the proper throttle body, the porting is supposedly worth about 10hp across the powerband, but i doubt you'd see much if anything while running a twin 60.
 

Canadian5.0

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I'm in the same boat with the 60. Couldn't justify another $650 which is like 900 cdn for an extra 10 hp. Maybe if a used one comes up. Would the twin 72 be too much for NA?
 

herzeleid05

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I'm in the same boat with the 60. Couldn't justify another $650 which is like 900 cdn for an extra 10 hp. Maybe if a used one comes up. Would the twin 72 be too much for NA?

Yeah, I'm about to install longtubes and keep my eyes out for a good deal on a used TB. I have not seen a twin 72. Everyone says go twin 67 or monoblade. I saw a used whipple big bore on Ebay but I assume that would be overkill.
 

KushBandit

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I'd port it when you get a larger throttle body. I'd also go with either the FRPP CJ twin 65mm(1517cfm) or the big SCJ Monoblade(1797cfm).
 

Stang Lover

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Somebody is selling a twin 65mm in the for sale section. I was gonna buy it but I bought a used monoblade today for a good price.
 

herzeleid05

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Problem solved... hopefully. I picked up the L&M twin 66 for a really good price. Just talked to Lund who says they will tune it but the TB is known to have issues. Guess I'll wait and see.
 

fordman2012

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does anyone have any numbers comparing throttle bodies? I keep hearing both sides of the coin with some people saying that it is a chocking point and others saying and even sighting a JPC test (I can not find anywhere) that there is really only 5whp difference between the twin 60 and twin65 and only another 2-3 whp on top of that going to a monoblade.
 

herzeleid05

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does anyone have any numbers comparing throttle bodies? I keep hearing both sides of the coin with some people saying that it is a chocking point and others saying and even sighting a JPC test (I can not find anywhere) that there is really only 5whp difference between the twin 60 and twin65 and only another 2-3 whp on top of that going to a monoblade.

Most say that it's about 5 rwhp peak, but better numbers on the curve. AED says that the twin 60 chokes the CJ and won't even tune it. I ended up going with Lund, who had it tuned pretty well. I am adding the TB, porting the CJ and adding Longtubes at the same time. Hopefully it pulls a little harder.
 

fordman2012

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Most say that it's about 5 rwhp peak, but better numbers on the curve. AED says that the twin 60 chokes the CJ and won't even tune it. I ended up going with Lund, who had it tuned pretty well. I am adding the TB, porting the CJ and adding Longtubes at the same time. Hopefully it pulls a little harder.

Yea I was curious so I asked JPC and they said that I would see more gains going to e85 then switching throttle bodies. So im going to think that its right around a 5rwhp difference peak and a little thru the curve too. not enough for me to spend $600 right now.
 

assasinator

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I'm in the same boat with the 60. Couldn't justify another $650 which is like 900 cdn for an extra 10 hp. Maybe if a used one comes up. Would the twin 72 be too much for NA?
10hp maybe, but I make 410rwtq because of the monoblade. There is a 30-40lb-ft difference. I make more torque than the stock manifold.

Sent from my K88 using the svtperformance.com mobile app
 

WhiTriCobra

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So ppl believe you'll get huge gains from going 60mm to 65mm? So pay 500-600 for 5mm and maybe a 3-5hp gain?? You could port your 60mm to make it flow better. That's my plan. No way the 60mm is choking it that bad. Also the portting the CJ is more like smoothing out areas. Without a flow bench I wouldn't start removing a lot of material.
So "porting" while you have the 60 will be fine until you get a bigger TB. If needed. But I would still ask my tuner what twin or sbtb they like. And a tuner not tuning a stock 60, where tuning it would be easier, makes no sense. I don't see how Ford can easily tune it on a GT500 that has a SC/more power but it chokes a CJ??
 
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WONSLOW302

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Any insight on the cobra jet with GT500 twin 60MM ?? Going to be pairing up that combo to my s550 soon. E85, catless longtubes. havent seen or heard of any power numbers from anyone. Most likely going to port the 60MM to 63MM
 

noldevin

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Any insight on the cobra jet with GT500 twin 60MM ?? Going to be pairing up that combo to my s550 soon. E85, catless longtubes. havent seen or heard of any power numbers from anyone. Most likely going to port the 60MM to 63MM

Twin 60 is way too small.
Twin 67 or Monoblade are the way to go, with the Twin 65 being in third place. IMO the twin 60 isn't even an option, it's like shooting yourself in the foot before you even start.
 

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