Just Finished Throttle Body Port / 99+ Sensor Swap, Read..

[cboney2000]

Well, a while ago I thought it would be cool to port out the bottom post of my 97 throttle body and leave the top alone. This is after I had yanked the MAF screen out. Well, just to say the least, the car idled bad, drove rough, and the RPM's stuck sometimes. So for the last two weeks I've been correcting the problem. I bought a 99+ style MAF sensor, ported out the top part of the post, waited a week and a half for the dang sensor, and then was in shock when it got here. The hole for the 97 style sensor was about a half inch. The hole required to fit the new sensor was 1.125", requiring me to go to a machine shop and pay $10 to get a bit big enough to drill that size hole (i tried everything to port it, the dremel would have taken years to do this much metal out, and the big shop drill did it evenly too). Next I spent two hours reshaping the front of the hole to fit the new sensor correctly, as it does not sit properly in the new round 1.125" hole. Then came the trimming and polishing, taking more time. I put it all back together with some gasket supet tack sealant (gator snot) to prevent leaks. I also installed a new MAF screen and ring and GM gasket. As far as how it drives, it drives wonderfully, idles very well, has noticeably more torque on tap (haven't tried top end yet), and RPM's never stick anymore. The kicker though is the price it has run me all together, see below for totals (doesnt include the price of a dremel or bits, i had em already):

GM Gasket: $6
GM MAF Screen: $24
GM MAF Ring: $27
GM 99+ MAF Sensor: $205 + $70 core
Gasket Sealant: $3
Throttle Body Cleaner: $5 (two bottles)

Total Work Hours: 6-7
Total Cost: $270

So was it worth it? The car drives like new and has more power on tap and there was a definate SOTP gain noticeable on bottom end. It cost me $270 and a lot of meticulous work and some driving back and forth between home, GM dealers, and a machine shop. I'm happy with it now though. Sorry I won't have any pictures up, I'm not touching the throttle body again unless necessary. However, I would be glad to lend any instructional help necessary if someone else wants to go through this. Magnus, I feel your pain on the project! But I am happy [img]graemlins/burnout.gif[/img]

[Magnus]

WTF!! Where did you buy your sensor?!?!??!? That price is ridiculous!!!!

Yea, I posted about all this back in the day..

I used a boring bit.. like a wood hole cutter.. the TB is soft aluminum so it worked fine.. Then I used the dremel to touch up the top so the new sensor would fit in.

[Takumi Fujiwara]

Looks like a new mod for me to look into, I had forgotten about Ur post on this a while back. hrm. But whats the Difference in having a 99 Maf sensor. Im getting SES codes from my MAF sensor ever since changing to the SLP CAI so Im interested in playing with the TB and doing the coolant bypass as well... or have I been hangin around the Ls1 guys too much

[Ironman24]

I feel your pain on that project. I went through the exact same thing as you did. Ported out the lower half of the TB, car ran like poop. So I took the TB to a machine shop and we played with it on the drill press. Got everything lined up and the 99 MAF sensor in. Before I couldn't use the AC during intown driving, it would stall out on me. Now she runs perfect. Big PROPS to Magnus for help on that project. And I'm with him, where in the heck did you buy that MAF sensor?? I paid 99 bucks and no core charge.

[BillyCobin]

Do you think the SOTP feeling came from the fact that you where driving around the car with a messed up TB for so long that you forgot what the car felt like when it was running strong?

[Dominic]

[img]graemlins/fluffy.gif[/img] I have an 02, I dont need no stinkin mods [img]graemlins/fluffy.gif[/img]

Thats a really neat thing though cboney [img]smile.gif[/img] Im glad it worked out okay!!

[Nachius]

<blockquote>quote:</font><hr>Originally posted by Magnus:
WTF!! Where did you buy your sensor?!?!??!? That price is ridiculous!!!!

Yea, I posted about all this back in the day..

I used a boring bit.. like a wood hole cutter.. the TB is soft aluminum so it worked fine.. Then I used the dremel to touch up the top so the new sensor would fit in.<hr></blockquote>

AND now I have it [img]smile.gif[/img]

Looks great worlds different than the pre 99's
If anyone needs pics of mags old TB hit me up as its still sitting in a box here! [img]graemlins/evilgrin.gif[/img]

[cboney2000]

The MAF sensor came from the GM dealer and it had a frickin $65 core on it, gmpartsdirect did as well! Heck if I know but oh well, I got the core back and it runs really well. The SOTP gain was definately more than just it running normal again, it's a good mod, just costly.