Throttle body

[Guest]

I am wanting to switch to a larger throttle body on my 93 3.1. Could somebody tell me what GM cars to look for to find a larger unit?

[IsaacHayes]

I don't know if a 56mm TB from a 3400 would bolt up or not. The linkage might be different. It might bolt up and you could swap your linkage.. not sure.

Anyways, the TB is not the main restriction on the 3.1mpfi motors. The intakes are. To get different ones, you need to swap to 3100/3400 heads as well.
Check this link out for ideas. http://www.domesticcrew.com/hybrid.html
3400 heads, intakes and the 56m TB would be a good boost for your motor. Or since you have a 93, you have all the motor mounts to just swap in a whole 3400 engine and go from there! That's what I would do. Info on that is availible on that site as well.

A larger TB on the 3.1 won't give you any gains really worth anything.

[Guest]

While I realize there are restrictions in my stock 3.1 system, I can pick up a used TB for $15 or less. If I only get 1-3 HP out of it, that is o.k.. I live in a condo, every time someone checks their oil, somebody gets bent. I have to drive the car to a friends house to do any work. Budget forbids me from doing anything very costly as well. I planned on a larger TB along with a CAI and larger exhaust and free flow muffler. A 3400 would be great...someday.

[IsaacHayes]

Yeah I live in a house but same thing goes. Plus I don't have a cherry picker or engine stand, or I'd have a 3400 with cam/etc goodies right now.

I seriously don't know if a 3400 (56mm tb) would bolt up to a gen2 (3.1mpfi) motor.

I know there were 62mm TB made (from billet) that went for ~300 at one time and I belive they made some for the gen2. Check out www.60degreev6.com they might have more info on the gen2 changes. They have 65mm TB but only for the gen3(3100/3400).

[KFLO 93 GT]

Well, a 3400 tb won't bolt up.  Different bolt pattern.  

Personally, having a 59mm tb on my 3.1, I wouldn't recommend getting one.  The intake manifolds don't flow enough to require a larger throttle body, the stock one can move enough air on it's own.  On my car I definately noticed more power up top, but I feel like I lost some lower end.  There are also some drivability issues, such as idle quality.  

If you plan on going deeper into it eventually, a tb is a good thing.  I've got ported intake manifolds, with a port matched plenum inlet to my 59mm tb.  I got mine from RSM Racing back in the day, for like $200.  Nowadays, they offer a 62mm unit, which is more expensive, plus I've been hearing some bad stories about their customer service lately.

[IsaacHayes]

Yup, thanks for backing me up. A TB should be the last thing you upgrade really. You need to flow a lot before the TB is a restriction.

I'd suggest CAI, Exhaust, and a UDP would give you a good boost. The CAI and UDP are probably the easiest to do. Exhuast if you have a place for the car to rest and a welder... (or pay a shop).

www.fastfwdperformance.com sells a UDP.

[KFLO 93 GT]

Yeah, if you're looking for good power for cheap, jump all over the FFP Underdrive pulley.  It makes 10 horsepower at 5000rpm, and that's where the 3.1 definately needs more umph.  That plus a homeade underhood intake, with piping and cone filter will another 5hp, plus make it sound tough too.  

Figure $110 for the pulley, $20 for a new serpentine belt (1 inch shorter than stock), and $50 for an intake.  That's only $180, and you're not going to make more power any cheaper way.  Take the other $20 out a proposed $200 and buy a strut tower brace from a 92+ cavy z24 at a junkyard.

That's a shitload of bang for $200.  

[twistedindy1]

I live in a condo and erich, steph and I did a motor swap right in my garage, if they get bent, piss on them.  You pay just like they do and just because they don't have the courage to do it there isn't your fault.