aftermarket throttle body problems??
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Joined: Dec 2005
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aftermarket throttle body problems?? looking into to getting like a throttle body for my LT1...just dont wanna have any idle problems or running problems, as ive read before....is it jsut a bad luck thing? or is there adjustments to be made when upgrading your TB....or is it just a nice bolt on and play 
Used to be that everyone was told to stay away from BBK's... And if you look at one compared to a nicer piece like AS&M, Holley, etc... You'll see why. Those BBK's have got to be the worst casting Ive ever seen.
Recently people have been having issues with the Holley, but Im convinced that most of these problems are user related. Rather than manufacturer related.
ANY AFTERMARKET TB IS GOING TO NEED ADJUSTMENTS TO WORK PROPERLY... Its not just a bolt-on thing.
1)The blades need to be adjusted so that they wont hang up in the closed position.
2)The TPS needs to be adjusted to spec
3)MOST need an IAC bypass hole to be drilled... Factory TB's have them aftermarket ones do not.
4)IAC counts need to be brought into spec by altering the size of the bypass hole and the Throttle blade position.
Recently people have been having issues with the Holley, but Im convinced that most of these problems are user related. Rather than manufacturer related.
ANY AFTERMARKET TB IS GOING TO NEED ADJUSTMENTS TO WORK PROPERLY... Its not just a bolt-on thing.
1)The blades need to be adjusted so that they wont hang up in the closed position.
2)The TPS needs to be adjusted to spec
3)MOST need an IAC bypass hole to be drilled... Factory TB's have them aftermarket ones do not.
4)IAC counts need to be brought into spec by altering the size of the bypass hole and the Throttle blade position.
I have a BBK and no problems. No casting problems as mentioned either. However this may be an issue as of late since I have had mine for a few years. I haven't had to drill mine out as my IAC counts are within range and my TPS was no problem to calibrate either. Not meant to be a hijack but just my experience. On that note, anything aftermarket might need some tweaking--kinda like tuning. I might not fool with a bigger TB til I had more mods. Might not see any gains as a bolt-on.
The only casting problems Ive seen are not anything that would cause it to work badly or what have you. Just the area in front of the bores is incredibly sloppy if you ask me. Ive already installed a few BBK's and while they all seem to work out correctly, there are gains to be had from smoothing the 'air-foil' in front of the bores.
I should have mentioned earlier, not all cars will need EVERY bit of the adjustments or 'tuning' I mentioned earlier. Ive found that the bolt on cars need the least amount of tweaking, while the heavily modded ones need the most tweaking.
I should have mentioned earlier, not all cars will need EVERY bit of the adjustments or 'tuning' I mentioned earlier. Ive found that the bolt on cars need the least amount of tweaking, while the heavily modded ones need the most tweaking.
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Originally Posted by Fire67
ANY AFTERMARKET TB IS GOING TO NEED ADJUSTMENTS TO WORK PROPERLY... Its not just a bolt-on thing.
1)The blades need to be adjusted so that they wont hang up in the closed position.
2)The TPS needs to be adjusted to spec
3)MOST need an IAC bypass hole to be drilled... Factory TB's have them aftermarket ones do not.
4)IAC counts need to be brought into spec by altering the size of the bypass hole and the Throttle blade position.
1)The blades need to be adjusted so that they wont hang up in the closed position.
2)The TPS needs to be adjusted to spec
3)MOST need an IAC bypass hole to be drilled... Factory TB's have them aftermarket ones do not.
4)IAC counts need to be brought into spec by altering the size of the bypass hole and the Throttle blade position.
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Originally Posted by Formula350
I have a BBK and I've never heard anyone having problems with them.
Originally Posted by Built LT1
I have a BBK and the two plates that come together with the throttle cable slipped and I burned up a few transmission before the problem was discovered. It was throwing the tps off and would not allow the computer to apply pressure to the clutches under wide open throttle. The two plates had to be drilled and a fitting inserted to hold the two together. No problems after that.
I went with a ported stocker(52mm) frmo MJBLUND) on ebay.He is also a member on camaroz28.com.
His job is awesome,comes fully powdercoat(red or black) and since its the stocker there is no problem or adjstement needed at all
And by the way you need approx(dyno proven) 500hp to max a 52mm one
His job is awesome,comes fully powdercoat(red or black) and since its the stocker there is no problem or adjstement needed at all
And by the way you need approx(dyno proven) 500hp to max a 52mm one
Originally Posted by always faster
I went with a ported stocker(52mm) frmo MJBLUND) on ebay.He is also a member on camaroz28.com.
His job is awesome,comes fully powdercoat(red or black) and since its the stocker there is no problem or adjstement needed at all
And by the way you need approx(dyno proven) 500hp to max a 52mm one
His job is awesome,comes fully powdercoat(red or black) and since its the stocker there is no problem or adjstement needed at all
And by the way you need approx(dyno proven) 500hp to max a 52mm one
Originally Posted by always faster
I went with a ported stocker(52mm) frmo MJBLUND) on ebay.He is also a member on camaroz28.com.
His job is awesome,comes fully powdercoat(red or black) and since its the stocker there is no problem or adjstement needed at all
And by the way you need approx(dyno proven) 500hp to max a 52mm one
His job is awesome,comes fully powdercoat(red or black) and since its the stocker there is no problem or adjstement needed at all
And by the way you need approx(dyno proven) 500hp to max a 52mm one
Originally Posted by LiENUS
Sounds more like he has a 4l60e, the 700r4 doesn't care what the TPS says, only a 4l60e would.
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From: Decatur, TN (N-W of Athens)
Originally Posted by Fire67
1)The blades need to be adjusted so that they wont hang up in the closed position.
2)The TPS needs to be adjusted to spec
3)MOST need an IAC bypass hole to be drilled... Factory TB's have them aftermarket ones do not.
4)IAC counts need to be brought into spec by altering the size of the bypass hole and the Throttle blade position.
2)The TPS needs to be adjusted to spec
3)MOST need an IAC bypass hole to be drilled... Factory TB's have them aftermarket ones do not.
4)IAC counts need to be brought into spec by altering the size of the bypass hole and the Throttle blade position.
Again, I've only seen people bitch about the Holley's.
I personally like how the BBK looks over the Holley since looks less aftermarket. The factory casting looks fine to me, which BBK basically looks like. Use the stock top plate and you really can't tell it's aftermarket.
Originally Posted by Formula350
1, 2, 3) All news to me. I plug and played mine on my TPI and plan to do the same when I install it on my LT1 (aside from changing my cars TPS to the older flat plug style)
Again, I've only seen people bitch about the Holley's.
I personally like how the BBK looks over the Holley since looks less aftermarket. The factory casting looks fine to me, which BBK basically looks like. Use the stock top plate and you really can't tell it's aftermarket.
Again, I've only seen people bitch about the Holley's.
I personally like how the BBK looks over the Holley since looks less aftermarket. The factory casting looks fine to me, which BBK basically looks like. Use the stock top plate and you really can't tell it's aftermarket.
Again, Steps 1-4 should be accomplished for ANY aftermarket TB install. Sure, you could probably get away with just slapping it on the car, but do it right and know it's right rather than trying to figure out what's wrong in the future because you didn't correctly set up your TB in the first place.
Originally Posted by Fastbird93
You got lucky then. My BBK needed polishing work to keep the blades from sticking, the TPS was WAY out of whack when initially installed, and with a big healthy Joe O cam in a 355 with ported heads, the car couldn't maintain an idle without a 11/64" IAC bypass drilled in.
Again, Steps 1-4 should be accomplished for ANY aftermarket TB install. Sure, you could probably get away with just slapping it on the car, but do it right and know it's right rather than trying to figure out what's wrong in the future because you didn't correctly set up your TB in the first place.
Again, Steps 1-4 should be accomplished for ANY aftermarket TB install. Sure, you could probably get away with just slapping it on the car, but do it right and know it's right rather than trying to figure out what's wrong in the future because you didn't correctly set up your TB in the first place.
Exactly, some people get lucky and go through the steps to find that they dont need to adjust anything but the tps. 9 out of 10 the TPS will be off enough to cause issues with how the pcm controls the motor.
If you just bolt a part on your car and dont check how it interacts with the systems it directly affects, then your just throwing cash in the wind IMHO.
If any of these checks are not performed, then you run the risk of something being out of whack, and causing you to actually lose performance. Especially with anything more than a bolt-on car.
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iTrader: (3)
Joined: Oct 2006
Posts: 7,564
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From: Decatur, TN (N-W of Athens)
heh I GAINED throttle response with mine. I bought it used, but it looked unmolested (aside from the modded IAC/Coolant plate on the bottom. He had cut the coolant side off
