Hi all,
I had a spare TB laying around so I decided to bore it out (so the holes are straight, not in an hour glass shape) and take the fins off the top of the holes. My question is, will doing this make my idle any higher? I put a V8 TB on my 3.9l Dakota and it made the idle about 200rpms higher and I didn't like that at all. Will boring this V8 TB make my 5.9l idle higher? Thanks in advance.

 

i would imagine it would. considering you didnt get larger discs to compensate for the bigger hole. i could be wrong though

 

Send your spare to the Fastman and have him do the work. He installs brass butterflies, smooths the bores, and makes a work of art.

 

I'm not going to make the entire hole any bigger, I'm just gonna make the top half above the discs bigger. The size of the hole around and beneath the disks will not be any larger so the stock disks will fit just like they did before.

I would send my TB to fastman but they want a boatload of money to do something that I can do myself.

 

gotcha. yea fastman is a little expensive, but you do get a completely like-new TB that looks bada**

 

No offense, but relatively speaking, the Fastman is not expensive. Have you guys even looked at his competitors? Holley wants double what the Fastman charges for a new TB that does the same thing.

 

well, im talking in comparison to buying a used one and doing it yourself(much cheaper)

 

Yes, but the Fastman bores out the entire TB for the 5.9 (52mm) and puts new butterflies in. Not dissing your skills, but unless you do the same, the Fastman's will be better.

 

you could always make your own butterflies. if you have the tools

 

I would like to see a tb with the fins cut off and bore made straight, like CSXfan is talking about doing, put up against the Fastman in a dyno test...bet the results wouldn't be $235 worth.