95 vette will not idle in closed loop
#21
Intermediate
Thread Starter
Just as a frame of reference, what size would you say the hole is in the stock throttle body? 1/4 inch? Also, put it into the red circle?
And I was wrong, upon measuring it, its a 52mm throttle body, not 58.
And I was wrong, upon measuring it, its a 52mm throttle body, not 58.
#22
I'd start by duplicating the hole size from your factory throttle body, and enlarge from there as necessary until you get the desired iac counts where you want them.
#25
Burning Brakes
1/4 inch is way too much. There were/are old threads talking about drilling hole in throttle bodies, as it was common years ago in the aftermarket ones. Do a search.
#26
Intermediate
Thread Starter
Update, ended up with a 10/64th hole in the throttle body, and car idles great now. Thank you everyone for the help.
The only other thing I came across was a reference to some sort of sleeving for the BBK throttle body's idle circuit back in the day, but I can't seem to find what this entails. Does anyone happen to know what this mod was?
The only other thing I came across was a reference to some sort of sleeving for the BBK throttle body's idle circuit back in the day, but I can't seem to find what this entails. Does anyone happen to know what this mod was?
The following users liked this post:
AmoriFati (03-09-2024)
#27
If I remember correctly, some aftermarket throttle bodies had cutouts in the casting from the IAC port to the plenum. Sleeving was a way to ensure the IAC air got into the idle manifold, and not the plenum. This is a stock throttle body from an early L98. See the cutouts? Some aftermarket throttle bodies duplicated this. Not good for an LT1. Glad everything is working now.
#29
Absolutely do that. Or look into the sleeve mod. Your BBK is dumping IAC air into the plenum, And that does look like a 52mm. BTW the stock manifold opening is 52mm as well. I have a BBK 58mm, and it does not have those channels. Just like this.
Last edited by MaxLean; 03-09-2024 at 08:27 PM. Reason: Added pic.
#30
Intermediate
Thread Starter
So! After everything, the issue did turn out to be a misstimed cam! It was off by a tooth as seen in the photo below.
And that was causing the running issues all along! Although, I still think drilling the hole was a good idea, as with it, my idle steps are 20-25 when warmed up.
And that was causing the running issues all along! Although, I still think drilling the hole was a good idea, as with it, my idle steps are 20-25 when warmed up.
The following users liked this post:
AmoriFati (05-15-2024)