TB's

[IanSzgatti]

1997 3100 SFI... what difference would a larger throttle body make, and what options are available? I ask because I've had this car only a little while, and while cleaning the TB I noticed how GatDamn small it is... thanks

[SappySE107]

3400 uses a 56mm vs your 52. On a small port manifold setup, I would upgrade to the larger port manifolds before I go any larger than 56mm. I have 62 and 65mm billet TBs on the store here. You can spend the same or more for a bored out stocker at 60-62mm elsewhere.

[MY91GT(Z)]

i have a 3400 tb ill sell for 30 shipped if ur interested and they swao pretty easy from what ive heard

[Bluegoose]

TB

If he doesn't want the 3400 TB, I'll take it for my sandrail.

Ronnie Smith

[IanSzgatti]

If he doesn't want the 3400 TB, I'll take it for my sandrail.

Ronnie Smith

go ahead... i can grab one around here easily.. a few pick yards around here

[IanSzgatti]

well i grabbed one today, a 56 mm from a Montana van... I think it's a 97 or 98, but either way, I'm here at the shop where I work now and just finished installing it... I realize I should upgrade to the larger port set up before exeeding 56mm from 52mm, and I'm wondering if that upper plenum from the 97 or 98 Montana van would bolt onto my LIM...
I brought my digital camera to the yard but neglected to take any pics on my plenum bolts to have a visual reference inside the yard... thinking further, I could have looked at any of the billion 3100's 50 feet across the yard... what are ya gonna do...
anyways... I'd post some pics up here if someone would show me how... for now it's time to go home and make sure everythings alright... thanks for the tips that got me started off here.

[IsaacHayes]

You need the LIM and UIM together. The large port upper won't bolt to a small port lower... ports are different and so is bolt pattern. The 96-98 3400 intakes should be a direct swap to your 97 (since you have the same egr, roller rockers, and threaded coolant fitting). Putting the metal felpro LIM gasket would be wise at that time.

Did you port your 3100 upper to match the 56mm TB? Otherwise it's not doing you much good but causing turbulence.

[IanSzgatti]

Did you port your 3100 upper to match the 56mm TB? Otherwise it's not doing you much good but causing turbulence.

good point... no i didnt port it, and you know what, I can HEAR the turbulence your talking about... I shit you not, it sounds like a high pitched swirling at certain RMPS, almost turbo-ish...haha... anyways, I do plan on doing the LIM gasket, and I'll do with the upper and lower 3400 at that time.

the good news is Isaac I found my vac leak to be that crappy little gromet we talked about before... so having done that too i should be better of in the mileage department... some photos of today and my shop...

http://i224.photobucket.com/albums/dd172/Szgatti/jsip_TB_swap_005.jpg

http://i224.photobucket.com/albums/dd172/Szgatti/jsip_TB_swap_006.jpg

http://i224.photobucket.com/albums/dd172/Szgatti/jsip_TB_swap_007.jpg

http://i224.photobucket.com/albums/dd172/Szgatti/work.jpg

http://i224.photobucket.com/albums/dd172/Szgatti/cars0021-1.jpg

this last photo here is of my ugliest, yet favorite car... now passed on

[IsaacHayes]

Yes the lip of the smaller intake will cause a whistle. I had a 56mm on my small port 3100 plenum before I swapped to the 3500 and it whistled. I didn't port it because I was going to go to the 3500 soon anyways. But I put the TB on just to make sure all the sensors still worked fine since I swapped em over before I swapped to the bigger intakes so if there was a problem I could rule out the TB...

[IanSzgatti]

yeah thats funny... it's a noise i like but it's not what I should hear. even my wife heard it on the way to dinner... noises aside though...

I can understand the benifits of having a less restrictive intake, but I am wondering how much the sensors compensate for before they are outside of they're range... for example;

TP is 10% open, and mass air flow reads 4 gps (humor me here), or the MAP reads XXX value for pressure...
now you slap on a larger TB and it is complementing increased flow capabilities of the larger port 3.4 stuff..... NOW
TP is at 10%, and the MAF reads higher or the MAP pressure is lower... does the computer at some point say... "hey, the TPS voltage is too low" ??

Now I understand guys are using tuners... but truthfully, that is a little beyond my scope for now. For now I'm trying to get an understanding of how much I can take intake and exhaust mods before getting to a point where my mixture is adversley affected.

[sharkey]

its not going to throw a tps code, its not as smart as you think it is. the tps is there mostly for transmission functions and acceleration enrichment. basicly it will tune off your maf, it detects xx amount of air going into the engine, so it will provide the fuel for that.

[IsaacHayes]

Hehhe yeah I do like the whistle noise. It's silly that we like things like that. You hear it sucking so I guess you think cool it's hungry!!! Reminds you of a turbine jet engine or something wanting to spool up.

Yeah you'll be fine. The computer can adjust a little bit, it's just when you change the VE of the engine so much that it gets out of the stock values. Like going from a 2.8 to a 3400, or a 3100 to a 3500, or adding headers and a cam. Stuff like that is a big difference.

Going to larger intakes and TB the car will still run fine. Any much more and a tuner will help you get more power out of it. I figure on the small port 3100 going to the larger intakes isn't that huge of a change, still nets you some good power as that's the main change they did in 2000+ to them and they got 10-15hp more.

EDIT: If you go too big of a TB for how much air the motor can flow, you will however reach max flow before the TB is open all the way. That means you'll get faster throttle response since you are flowing more air faster per pedal movement, but once you get to say 80% throttle, you are at max flow and going to 100% isn't going to make more power or feel like it pulls more. I don't like that feeling. I've drove 4 cylinder cars that were like that. They were really responsive down low making you think it had balls, but when you floored it the difference from 1/3 throttle to full throttle was exactly the same amount of pull....