Mystic97Z

hey, installed a bbk 58mm throttle body and slp cold air yesterday, had it idleing in my garage and adjusted the idle screw so my iac counts were where they should be, when i drive it wants to stick around 2,000 rpms. like if i'm ont he highway at 80 mph and hold the clutch in, it stays at 2,000, when i come to a stop and am at a complete stop it will stay at 2,000 rpms for like 5-7 seconds before slowly setting down to about 900. and if i shift at 1500 or 1600 rpms, inbetween shifts it will go up to 2,000 also.
my dad said we could grind ( i think ) or adjust the throttle position sensor? what else could be causing this problem.
-Jason
thanks for any help as i wold like to get this fixed asap.
BTW, a huge difference with the tb and cold air, i guess my engine was sufficating before, but i noticed a very nice improvement in power and the throttle response is 100 times better.

LWillmann

congrats on the upgrade and improved throttle response. MY car is just mildly modded (just bolt-ons) and I noticed a really nice throttle response improvement when I went to a 52mm TB. Sadly though the TB I have is messed up and needs to be fixed.

I have read that the BBK TBs need some adjustment for the TPS to be proper so they idle right. So you might try elongating the holes in the sensor and give it a shot!

Injuneer

Before you start drilling and grinding, check the closed throttle TPS voltage. It should be between 0.20-0.90V, with a preferred value in the range fo 0.60-0.67V. Thats sort of the final step in setting up a new TB.

detroit1994z28

BBK THROTTLE BODYS ARE Known to stick. They are Junk. For about $150.00 you could have a 58 hollley throttle body. There about $450.00. Every one had similar problems with that throttle body. The guy over the phone that sells these told me holley is was better then bbk. He said bbk throttle bodys are junk. It was thunder racing. - Yeah do research next time. BBK- ARE JUNK -

blk95zm6

Hmmmmmmm....."the guy that SELLS holley's say's the BBK's are junk"..... Um, what did you expect him to say?
HE SELLS HOLLEY'S! My BBK 52mm works just fine. 451 RWHP & 438 RWTQ.

Injuneer

Amazing.... so much so that its laughable .......

I bought the 58mm Holley, and it was a work of art..... beautiful billet construction, polished up real nice, the red blades were a nice touch. Then I put it on the car, and the problems started. The annular space between the blades and the bores was so great you could read a newspaper through the closed blades. The steel "throttle stop" lever was held loosely in a thin channel in the billet aluminum quadrent, and would allow the blades to move at the end of the travel, when they were supposed to stop.... really threw my MoTeC TPS calibration all to hell, since it needed perfectly defined closed and open throttle TPS voltages to prorate the throttle position - critical to a setup running alpha-N programming.

Eventually, I took the Holley apart, and rebuilt it so it was a decent product.... larger blades, pinned the stop lever to the quadrent, etc.... a hell of a lot of work to have to put into a $400 (that't what it sold for when I bought it from T. Byrne in 1999) product.

While I was rebuilding the Holley POS, I borrowed a 58mm BBK from my good friend George Baxter.... the one he had used for nearly 4 years on his 1,125HP Vortech S/C'd 383 LT1. It worked perfectly, in spite of 4 years of heavy abuse. Didn't look as good as the Holley, by a long shot, but it sure functioned a lot better.

But to say that BBK is JUNK displays an amazing level of chutzpah.

Mystic97Z

at first the tps voltage was .90, but the iac was too high, got that down and the tps went to .94, we are going to do some adjusting on it in a little bit, i'll post the results for anyone else having a similar problem. my dad has a gm scanner which makes things very nice! thanks for all the help.

FYI i did a ton of research on this board and as well as many others, i read pro's and cons of each, $$ wasn't an issue at all between the bbk and the holley, i wanted a holley so much more than a bbk cuz they look alot nicer, but i read that they have problems w/ the blades sticking. either way they're both aftermarket so we all know neither of them will bolt up and work right lol.
-Jason

Mystic97Z

drilled out the holes on the tps, got the voltage down to .53, its a ton better, but still does it just a bit. so that was my problem.
-Jason

BigJustinZ28

glad you found the problem , I bought a new tps before I realized the old one was out of adjustment lol

Heatmaker

I"ve been looking at the BBk's VS the AS&M's

Minus the nice polish and the Better looking built in AUrfoil are he AS&M's that much better? I thought they redisigned the BBK's and took care of the sticking issues??? weren't those the earlier models that had that problem?

Are the BBK/Edelbrock versions troublefree?

Buttercup

Pretty much all aftermarket throttle body castings need work to be "perfect"

My 58mm BBK works fantastic. Before I even put it on the car I learned from others and made the appropriate changes. The stop was adjusted, the TPS sensor position was adjusted, the IAC port was isolated from the main plenum, and the IAC bleed hole was drilled.

You'd think with the kind of money you pay for these damn things they'd be ready to go, as is

97WS6SCharged

There's no such thing as trouble free.

Bud M

Saw that one coming from a mile away

350 HRSS

Ok so this is what I am considering installing.

What all exactly do I need to do to this TB before I install it? Can someone give me some detailed instructions?

Thanks

steve40

when i installed my 52mm tb i had sticking problems with it. would take it off and it would for flawlessly in my hand.

i put it back on and tightened the bolts in a x pattern and only went about a 1/4 turn past once they where snug against the gasket. been fine since then. i figure that i must of overtightened it to the intake.

hope you find the problem