What exactly are they different?

If I won't get any forced induction, which is better??

 

One has one size primaries, and the other is larger. Might as well get 1 and 7/8's, seems like they are becoming more widely available.

 

17/8 will give you a little more topend while and you will also loose a little more lowend torque then you would with 1 3/4. It wont be as noticable as 1 5/8 compared to 1 7/8. personally i recommend 1 7/8 because I race on the street and track. You race in the topend not the lowend. in the end it matters what your needs/wants are out of your car, but between the two their is not a big difference espcially if you are mostly stock

 

1 7/8" flow about 13% more than a 1 3/4".

 

tsp 1 7/8 here for me and fit great with poly mounts installed

 

I agree.

 

Thanks guys.

What about sound difference? one is deeper and louder????

 

probably not. Go with the 1 7/8"

 

People who say you "lose low end" are misinformed and are buying into a myth. Go for the 1 7/8 and get a dyno tune and prepare to be happy.

 

I would just go 1 7/8 and be done that is what I did. No lack of low end here.

 

I agree, TSP has seen gains on a stock LS1 with 1 7/8 over 1 3/4 on the engine dyno.

 

1 7/8's all the way, they will have less wiggle room around things but you will never have to get another set. You can grow into them and sacrifice nothing while lighlty modded. They make more power with N20 but they are nearly indentical when FI'd (from CF posts). If you ever go larger cubes though, you will have them already.

Search Corvette Forums for more info, those guys are nuts about having these threads.

 

Here is a back to back comparison:

http://forums.corvetteforum.com/c5-t...h-results.html

No loss of torque.

 

1 7/8, u never know when you'll be running into any power adders

 

Agreed...as for a sound difference, they are almost identical (I went from Kooks 1-3/4" to Kooks 1-7/8"), but the 1-7/8" headers sound a bit more pissed.

If I had to do it over again (and not spend money for headers twice), I would have went with 1-7/8" headers from the beginning.

 

I switched this summer from flowtech 1 3/4 to TSP 1 7/8, good decision, better sound much better power especially up top

 

i went 1 7/8 kooks with cats and i couldnt be happier