KilerTA

iTrader: (70)

I just did my first cam swap and decited to go with the TV2 so far ive been very impressed. But the question becomes when drilling the whole in the TB is there a standard bit size for every cam or a math eqation you can do to figure out what size hole to drill? like a 224/244 get a 3/16 and if you go over 230 you need to go with this size I though i might just ask

SPEEDYws6

iTrader: (9)

Every car is different so that would not work. The best thing you can do is drill a new hole... start small and work your way up, checking your iac counts with a scan tool until you get them inline. 40-60 with a/c off is a good starting point

PREDATOR-Z

Actualy before you start drilling just do a TPS relearn.
1> Turn ignition off
2> unplug TPS sensor at TB (botom on driver side)
3> open the TB blade a bit via idle screw
4> Turn ignition on (do not crank)
5> wait 30 seconds
6> Turn ignition off
7> Plug TPS sensor back on
8> crank motor and see if it idles better

9> repeat untill idle is to your taste.

99blancoSS

iTrader: (115)

Do Not drill a bigger hole in your TB blade.

radkon

iTrader: (2)

Drilling should be a last resort after the aforementioned TPS adjustments, idle air adjustments and a good tune.

KilerTA

iTrader: (70)

It hates cold starts thats all i can say we told it to idel at 1100 rpms and it wont hold till its warm iknow thats all in the tuneing but i was just asking since thats one of the remidies that some people do thanks

tim99ws6

iTrader: (31)

what size cam are you running that would not idle at 1100 with????

Even my Trex in my 346ci car idled at 950(didn't like it, but never stalled out)

SPEEDYws6

iTrader: (9)

If your going to adjust the throttle balde be sure to keep the tps voltage under .69v

Edit: I used both methods to tune my car. I drilled a hole to get it close and then I fine tuned it with the screw. But my car has a very big cam for a 346, others may be able to just adjust the blade.

gillbot

iTrader: (27)

I drilled a hole, no matter what I tried to do I couldn't crack the blade as it would not reset. You can come and look at the hole in mine if you want an idea, my car idles perfect so it should get you close.

We just went up in VERY small incriments until we got the idle perfect.

Ls2Sonoma

iTrader: (4)

whats the big deal about drilling a hole in the plate? i mean, if you take the throttle body off, so no metal fillings get in the engine. just my thoughts, it wouldnt be a bad idea as long as you dont go too big.

KilerTA

iTrader: (70)

Its a torquer 2 in a 347 from tsp i wont hold an idel at 1100 rpms thanks gill i might have to take you up on that next time me and zander get tuneing on the car again well see

SPEEDYws6

iTrader: (9)

What do you mean it won't hold idle? does it surge?

Superjoe

iTrader: (2)

Geezuz, don't drill a hole in the TB! Just take the idle adjust screw out and put it in from the top. Once I had mine run all the way in from the top I backed it out a total of 3/4 of a turn I got all the adjust I needed, without drilling a permanent hole.

Billiumss

iTrader: (11)

Let's just say GM put the stock hole in there for a reason, I'm going to assume they know a bit more about tuning these engines than we do.

Sure you can drill it out, but not too much...

SPEEDYws6

iTrader: (9)

It doesn't matter what you do to open it up, cracking the blade does the same thing as drilling the hole. I can assure you though, if GM put a bigger cam in a ls1 they would enlarge the hole.

PREDATOR-Z

Guys, something you maybe forgetting is that by enlarging he hole and not relearning TPS you are actualy messing with your tune.

J-Rod

Of course you can always just learn to tune your car, and leave the drill bits for things you should actually drill holes in (not the TB).

Billiumss

iTrader: (11)

So you are saying GM f'd up and doesn't have a clue as to why they put a hole in the TB blade in the first place? I'm going to bet they know more than anyone on this board including HPT and EFI Live. GM were the ones that designed it from the ground up.

Repeat after me - "GM PUT THE THROTTLE BLADE HOLE IN FOR A REASON"

Sure you "don't have to" drill a hole, I didn't on my H&C car, but it makes it way easier to dial in the tune (idle). I have countless hours into my idle tuning, (drives and idles like stock) most shops wouldn't spend that much time on it since they would go broke working for peanuts.


$.02

SPEEDYws6

iTrader: (9)

Thats about the dumbest post I've ever seen. There is no way your going to get any of the bigger cams to idle properly with software alone.

N4cer

iTrader: (11)

Do you reset the idle screw or leave it?