bclounch

Just bought an ATK LQ4 head/cam motor and deciding on headers. Specs on cam are 216/224 551 lift 114LSA. 9.5.1 compression with LQ4 heads. Would I benefit from 1 7/8 primaries or should I stick with 1 3/4. Going with TSP header and Y combo just need to figure out what size to go with.
Thanks

Mercier

iTrader: (15)

That's a fairly powerful but comparatively mild setup. I think you would be better off with the smaller primaries.

bclounch

Claims 460 HP and 470 TQ. Guess we will see what it puts down in a few weeks. Think I may just go with the 1 7/8 for future 408 build.

Mercier

iTrader: (15)

I don't think it would hurt you much of any if you are looking to upgrade in the future.

ragtopz28

iTrader: (57)

What's it going in? The 1 7/8" may hurt a tad on the bottom end, but will "let-er-eat" after that. I just went with 1 7/8" on a SBE LS1 and gained 19hp (on the motor) + they love the N20 too!!

bclounch

Going into a 01 Trans Am. 4L60E. Hopefully the transmission and rear end can take it. And i went with some Speed Engineering 1 7/8th with a TSP off road Y.

ragtopz28

iTrader: (57)

That's a great combo. I got the SE's best bang for buck header I've seen and the install was cheese cake!

gagliano7

If you plan on a 408 in the future you might as well get the 1 7/8 so you will already be set. I am planning on getting the atk motor in the spring for my truck so it will be nice to see what #'s this puts down to the wheels.

bclounch

Finally got the T/A on the dyno. Here is the run .

Pulls in 2nd so numbers were a little low
365 hp
399 tq

foxsl

iTrader: (1)

That's about 450-460 hp and 480-490 ft lbs of trq at the engine. Seems like it was close to the estimate

gagliano7

That is a real nice torque curve. How does it feel on the road?

Rise of the Phoenix

iTrader: (27)

I would buy the 1 7/8 headers and not look back.

CattleAc

iTrader: (7)

He took your advice...ahead of time...

bclounch

Thing is a freaking torque monster now and pulls surprisingly well till about 6300. It has already taken down a 2015 5.0, 2012 Camaro ( I did that with bolt-ons only before), and my buddies stage 2 sti. I am pretty happy with how it turned out. Don't see any bottom end missing with the bigger primaries so I guess yall were right.