Port and polishing TB..
TECH Addict
Joined: Dec 2001
Posts: 2,298
Likes: 2
From: new england
Re: Port and polishing TB.. Remember you need two holes in late model LS1 T.B. one for pcv system vent and other for I.A.C. i make mine around 5/16" each. Also dont forget trimming blade screws and thinning shaft, also full throttle mod is worth something also.Last but not least put idle screw in from top so you can adjust with out removing T.B. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
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TECH Junkie
Joined: Nov 2001
Posts: 3,604
Likes: 0
From: Los Angeles
Re: Port and polishing TB.. Thanks for the comments.
I used JB Weld and made sure I got the stuff WAY down into the hole, filled it in inside there too so that there was no way it could become dislodged during engine operation.
And guys, keep in mind the pics are a C5 throttle body. The principal is the same for the Fbody throttle body except you have to put 2 holes instead of one (as stated)...C5's dont have IAC, nor a bumpstop mod, nor an idle set screw. Either way, drill 2 holes instead of one and you are set to go on an fbody.
I think the hole was 1/4" or so. Its just a fresh air vent tube for PCV, nothing that requires any sort of exact sized hole.
I used JB Weld and made sure I got the stuff WAY down into the hole, filled it in inside there too so that there was no way it could become dislodged during engine operation.
And guys, keep in mind the pics are a C5 throttle body. The principal is the same for the Fbody throttle body except you have to put 2 holes instead of one (as stated)...C5's dont have IAC, nor a bumpstop mod, nor an idle set screw. Either way, drill 2 holes instead of one and you are set to go on an fbody.
I think the hole was 1/4" or so. Its just a fresh air vent tube for PCV, nothing that requires any sort of exact sized hole.
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On The Tree
Joined: Aug 2002
Posts: 187
Likes: 0
From: Louisville, KY
Re: Port and polishing TB.. Def nice job, does anyone know how much hp a come just like this will give you? jmX can you feel a difference? I might have to try that this weekend before I make my last run at the track before it closes for winter <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
TECH Junkie
Joined: Nov 2001
Posts: 3,604
Likes: 0
From: Los Angeles
Re: Port and polishing TB.. I recently started porting mine (with a dremmel). I still have a lot of work to do, but you can see its not all that hard. Just get a sanding/grinding set of bits from walmart (mine cost me $11.96 I think), sand down the big ridge and make it a smooth transition to the mouth. Grind down the shaft the blade sits on a bit, but DONT change the bore size around the blade or else you'll screw up your idle.
<img src="http://home.austin.rr.com/tyr/c5/tb_port.jpg" alt=" - " />
<img src="http://home.austin.rr.com/tyr/c5/tb_port.jpg" alt=" - " />
On The Tree
Joined: Aug 2002
Posts: 187
Likes: 0
From: Louisville, KY
Re: Port and polishing TB.. I just did this today, and, what kind of dremel tools did you use!? The sandpaper ones wore out on that metal in like 10 seconds. I ended up using like grinding stone kinds, those worked, but slow and more rough that yours. What did you use? Man I guess this looked easier than it was...oh well at least ill gain SOMETHING...
TECH Addict
Joined: Dec 2001
Posts: 2,298
Likes: 2
From: new england
Re: Port and polishing TB.. I port them with carbide burrs,polish with sanding roll cartridges. As for performance difference people state 6 to 10 hp, but i will say this mod smooths out turbulence in intake path and this is something you can feel when driving in all ranges.Your car will growl louder too with wot mod and port polish, all good in my book! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
TECH Apprentice
Joined: Jan 2002
Posts: 337
Likes: 0
From: O'Fallon-MO.
Re: Port and polishing TB.. Hey guys,as far as epoxy goes.Go to Sears hardware in the plumbers section and get some stuff called plumbers epoxy.It comes in a tube,and it like a chemical reation when you work it together like play-doe.Then you can work it with your hands real well.Its hard as a rock withih 5 min so you have to work fast,and bonds to all metals.Even says on the tube automotive use <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> This is the ****!!! and only $6.
Good luck
Mark
BTW: I'll take some pics sometime if you guys want.
Good luck
Mark
BTW: I'll take some pics sometime if you guys want.
TECH Addict
Joined: Nov 2001
Posts: 2,003
Likes: 0
From: Live Oak, FL - in the woods where the creatures lurk.
Re: Port and polishing TB.. JMX, good info as usual.
As far as the (2) hole sizes go on the F-Bod TB epoxy fill, the hole into the IAC seems to be more critical to maintain decent idle. I started w/a 1/4" and gradually moved to roughly a 3/8" hole. I'm thinking that that is probably max opening for decent IAC operation. For those having idle problems w/cam, might want to square that away beforehand.
As far as the (2) hole sizes go on the F-Bod TB epoxy fill, the hole into the IAC seems to be more critical to maintain decent idle. I started w/a 1/4" and gradually moved to roughly a 3/8" hole. I'm thinking that that is probably max opening for decent IAC operation. For those having idle problems w/cam, might want to square that away beforehand.
On The Tree
Joined: Aug 2002
Posts: 187
Likes: 0
From: Louisville, KY
Re: Port and polishing TB.. Could you take pics slick? Another thing, I dont know about the year of the car with the pics above, but mines a 98 and the area where the holes are for the IAT and something else are MUUUCH bigger than his looked, like double. There are 2 holes, one that goes to a tube to a valve cover the other a little sensor. Anyone have pics of the same thing im talking about? where should i put the hole in this kind?
