so, i got a check the other day from a insurance company, were some lady had hit me in my dad's truck,and they paid me 500.00 I wanted to know if i should get a 52 mm TB,mod's in my sig, i want to know if i would see any real gain. I was also thinking about picking up a LS1 driveshaft and wanted to know if it would help any too.

 

my car has bbk throttle body and i dont think it feels any faster than ones without it. But im no expert.

 

You won't need a bigger TB until you at least get a cam. Our heads are a much bigger restriction on airflow. Get some gears, you'll definitely feel those right away.

 

I'd like to see some definitive dyno testing, the conventional wisdom around these boards (without much in the way of real numbers as far as I know) is quick to dismiss them. There have been more than a few magazine tests that seem to indicate they're fairly decent however. I take them somewhat with a grain of salt being as they could be biased somewhat, but they're at least some numbers.

This article I scanned for instance got 10 rwhp and 14 ft-lbs from a 52mm TB after aleady having a catback and cold air intake (that yielded around 6 rwhp and 9 rwhp respectively)... If those numbers are indeed correct I'd think the 52mm is more than worth it with a couple mods... You decide. http://bellsouthpwp.net/j/s/jstriet/LT1article1.jpg

 

I'm not sure I agree with the heads being a restriction at this point but gears would be a nice upgrade for you. The 52mm tb gave me a solid 10 hp at the wheels with my small cam over the stock one. I don't remember seeing if you had new valvesprings or not. That would be a nice piece of insurance.

 

If you wanna get the 52mm TB, then go for it. I would suggest one of the ported stock units you can find on ebay. The guy will even give you some money back if you send him your stock one back to him. IMO, the gears would give the greatest performance increase, and a 1.6RR/spring combo would be a good way to prepare your car for a cam. Your choice. The TB is plug and play, the springs require a good bit of work, but you can do them yourself, but the gears should only be installed by a professional. Maybe that will help your decision. With $500 you should be able to get both the TB and gears, if you can find some good deals. Good luck.

 

Use the $$ for valve train upgrade. Get some 1.6RRs and some dual springs (don't get any cheap crap) if you go with non-self aligning, you will need guide plates and hardened push rods. Don't go any bigger on the spring than you would need given the type of cam you would go with, but do go with at least a dual spring that will fit your stock seats. (plenty of options).

You can wait on a larger TB, the stocker should be fine until you do heads and cam.

Doing a really nice job on your valve train should give you increased performance, less friction, and better valve control. JMHO