Drilling the throttle body

[Kamauxx]

So, new cam is starving for air. What's the process of drilling the throttle body? Is it as simple as taking it off, drilling 3/16, then sanding it down to assure no shavings can get into the engine and replacing it?

Car's idle is beyond rough and has killed twice since being tuned. Tuner has done just about all he can since I have stock heads and manifold.

Also, will this actually help with the car stalling at idle?

[blue02Z]

you dont drill the throttle body but you port and polish it. make sure someone who does it knows what they are doing. check out mark shaner at s2performance.com, he did mine and he is good, most people like his work. you really need to ditch that ls1 intake for an ls6

[Danger731]

If you are going to change intakes get a F.A.S.T.

[shady milkman]

If you are going to change intakes get a F.A.S.T.

see the problem is you jumped the gun with the cam install. the cam although one of the biggest power adders needs to have the supporting mods to let it work efficiently. First things first..like danger said get the fast 90 90 combo or atleast the fast intake. then you MUST get headers. i'd suggest long tubes. then get a nice catback or even duals or dumps.. then get it tuned..you will see alot more gains.

[Firebirdjones]

I believe he is talking about drilling the throttle blade, not the throttle body.
On a side note,,,,,,This is a situation that I run into while tuning carburated customer cars with big cams.
What happens is the idle screw is turned in so far the transfer slot is exposed that transitions the carburator from the idle circuit to the main circuit and assentially causes the car to idle off of the main circuit and renders the idle mixture screws inoperative.

After checking timing and other variables, a small hole is drilled in both front throttle blades, this allows the idle screw to be backed off slightly, and covering that transfer slot, which enables the idle mixture screws and makes the carb run off the idle circuit as intended, then proper A/F ratio can be adjusted with the idle mixture screws at this point.

It's a process I have done many times on various style carbs, and I have heard of this on the fuel injection setups as well with large cams. Guess it helps these tuners dial in the idle easier when large by huge cams are installed. But without other info on your setup and what has been done already I am not sure how anyone could give you a positive direction to go in.

[0rion]

what size is your cam an is it an a4 or m6? You can always use the set screw method since it's easily reversed if it doesn't work out instead of drilling. Do you have any supporting mods for the cam?

[Kamauxx]

see the problem is you jumped the gun with the cam install. the cam although one of the biggest power adders needs to have the supporting mods to let it work efficiently. First things first..like danger said get the fast 90 90 combo or atleast the fast intake. then you MUST get headers. i'd suggest long tubes. then get a nice catback or even duals or dumps.. then get it tuned..you will see alot more gains.

Negative. You jumped the gun. I already have lts, true duals, and a tune. Heh...my tune just sucks balls!

[Kamauxx]

what size is your cam an is it an a4 or m6? You can always use the set screw method since it's easily reversed if it doesn't work out instead of drilling. Do you have any supporting mods for the cam?

It's an A4. I'm bringing it back to the tuner Monday. He already drilled the blade, and that didn't help. Looks like he's about to have to fix the tune AFTER his manage buys me a new blade.

[shady milkman]

Negative. You jumped the gun. I already have lts, true duals, and a tune. Heh...my tune just sucks balls!

wow sorry man..i was losing my mind that day..i was at class and posting on a few threads..i could have sworn you said the cam is all you had but my bad man.

[fbodynut]

Hey Kamauxx,

What kind of gains did you see with the tune? I am running long tubes, cat back, and cold air. I am toying around with getting a tune, or waiting untill I do the cam. With stock cam, 400 bucks for about 10 hp is what the tuner told me here. Let me know what you end up with if... you don't mind please
Thanks

[Kamauxx]

I made 380. I'd guess with an ls6 intake I would have been over 400.

I've got Lt's, torquer v3, ASP UD pulley, true duals, lid...

My numbers are lower than what my car is actually putting out because I also have a stall and 3.73 gears. I estimate I'm making appx. 390 ish.

Tune added about 22 rwhp to the car.

[fbodynut]

Thanks for the info. I just don't want to spend 400 bucks for 10 hp if there is alot more to be made from a tune after a cam.
So the 22hp you made from the tune was on top of the hp you picked up from the cam, right?

[Kamauxx]

That's correct.

[fbodynut]

That's correct.

Cool, so I will definately wait until I get the cam in to do the tune.

Thanks for the info.

[0rion]

It's an A4. I'm bringing it back to the tuner Monday. He already drilled the blade, and that didn't help. Looks like he's about to have to fix the tune AFTER his manage buys me a new blade.

I wouldn't sweat the blade that much. Very common and that's a fairly large cam. What lsa did you get it on? Sounds like the tune just needs some more work. I'm sure they'll get it squared away. Who's tuning it?

[shady milkman]

what..do you have a ls6 or aftermarket intake manifold?? if not..invest in one of those

[Kamauxx]

I wouldn't sweat the blade that much. Very common and that's a fairly large cam. What lsa did you get it on? Sounds like the tune just needs some more work. I'm sure they'll get it squared away. Who's tuning it?

It's a place called MC Racing in KC, MO. Brought it to them today, seems to be doing ALOT better!

[Kamauxx]

what..do you have a ls6 or aftermarket intake manifold?? if not..invest in one of those

That's my next mod...gotta get a winter beater first though.

[shady milkman]

nice..get the manifold then re-tune it..i bet she will fix her self with the manifold and re-tune