86White_T/A305

Im getting ready to pull the trigger on some hawks 1 3/4 lts with 3" collectors among my list of winter upgrades of 243 heads.I need opinions or see pics of some setups concerning using electric cutouts.id like to run dual cutouts and then merge to a 3 inch cat back.I have plans to also get sfc's later and dont want to hinder problems later installing them.I want things to be as tucked up as possible since Im riding on sportline springs and putting in tokico strut/shocks. Are dual cutouts overkill..if there is such a thing? How tight are other cars running full 3inch exhuast on lowered swapped cars?

QwkTrip

iTrader: (22)

I would take the money you were going to spend on the cutouts and get the 1-7/8 inch primary headers and 3-1/2" or 4" exhaust. That's going to make more power for you.

86White_T/A305

I already have 3 inch cat back magnaflow,just looking for good ground clearance with the rest amount of fitment issues with my future mods in mind.I sold on a cutout..whether its single or dual ...I havent decided.1 7/8 hawks headers are out of my budget range for just the headers alone.I dont think 1 3/4 long tubes with 3 inch collect,3 inch y pipe to the rest of my 3 inch exhaust is going to be choking my motor for little mods...it may make maybe 10-20hp uptop going bigger? Cutout can make that up for dyno purposes I would hope.

QwkTrip

iTrader: (22)

3" single pipe is flat out too small for an LS1 engine. That's why you have two 3" collectors.

3.5" single is equivalent to 2.5" duals. 4" single is a bit smaller than 3" duals.

Pocket

iTrader: (24)

Thats silly, 3" single exhaust systems have supported well over 500hp, mostly proven in the LSx family

FWIW, you'll drag the Hawks header collectors before the rest of your exhaust

LivinLarge

Unless you are making massive amounts of HP, 3' exhaust is fine. A cutout will help with power and sound but will kick your a$$ on ground clearence.

86White_T/A305

My 6.0 isnt going to be a heavily modded beast..its just small cam and change to 243 heads..that combo at best might make 400whp. 3.5-4inch might to slight overkill for what im doing and i doubt will be enough back pressure for a daily driver.

How low do the new hawk headers hang down,i thought they have been improved and not so much an issue?

cam-

Im on sportlines. OLD sportlines too so they have settled in and my car is in the weeeeeeeeds. Current set up is a cammed 6.2L with Hawks 1 3/4" headers with 2.5" y into single three inch and its tucked up tight with a drews crossmember running to a hooker Aerochamber. Runs great, sounds killer, my QT bell is the lowest point on the car now. If your in the Thornhill area sometime over the winter and want to see it for yourself your welcome too.

Not really a fan of cutouts and trying to fit two under the pans would be a tall order

86White_T/A305

My sportlines are about 7yrs old on blown shock/struts and the car isnt that low..odd.I have the hawks cross member but I dont think they allow as much room as the drews.I feel as if my current manifold/dual 2.5 catted y is a severe bottle neck.I know asking for dual cutouts is alot lol but a single would be fine.

Its been awhile since Ive seen your build Cam-..do you have pics during the exhaust install floating around here? Id love to see here the car inperson anytime lol.Im in the scarborough area.

cam-

There might be a couple of pics in some of the exhaust links in the sticky but not much.

86White_T/A305

Awesome thanks,Ill look up your posts,do you have any sound clips or vids?

cam-

No clips

STREETDEMON

a single 3" cutout would be fine for what you are trying to achieve. mine is mounted in the i-pipe under the rear passenger seat. it needs some attention and new thicker gaskets. it leaks a tiny amount, enough to drive me crazy!

dual 3" exhaust is way overkill for anything on the street...what you have planned should suit you well!

Orr89RocZ

iTrader: (20)

I have seen this too but doesnt mean its right for the combo. I have seen gains posted with larger than 3" exhaust. Flow area in single 3" pipe becomes restrictive on 300-350 whp. Thats bolt on ls1 range. It will continue to make power with that but backpressure starts to build up. If headers and exhaust are tuned right and cammed to match then more power can be made with the larger exhaust. Some mild ls motors pick up power using larger than recommended headers but some of that can be collector design differences. But it seems potential is there on larger exhaust sides

if you have any kind of cammed lsx i would feel better with 3.5-4" single. Dual cutouts could be done but its gonna be hard to fit

1nasty86

iTrader: (5)

my ls2 runs fine with the exhaust i have..... 1 3/4 hawks headers with 3 inch collectors into a flowmaster merge into a single 3 1/2 pipe and into a 3 1/2 cutout and then another flowmaster 3 1/2-3 reducer then it goes over the axle and into my maganflow catback..... i see about a 10-15 hp inmcrease every dyno pull closed vs. open... and as much as i dislike spohn their sfc's tuck up very nice...