LQ4 exhaust size
well I guess I will start, the exhaust size depends on what is done to the engine. I would think a lower compression LQ4, stock cam, headers, would be 2.5 duals, if the engine is hopped up some 10.5 to 1 or more, cam, headers, ported heads, would be 3.0 duals. Just my thought,
I am going with 3 inch X pipe, into 2.5 mufflers, to 2.5 tail pipes. I have a LQ4, LS1 intake, headers, small cam, and a m6 trans. 93 Mustang
I am going with 3 inch X pipe, into 2.5 mufflers, to 2.5 tail pipes. I have a LQ4, LS1 intake, headers, small cam, and a m6 trans. 93 Mustang
With a truck id chose 2.5 because with 3in you will lose some low speed torque which you def need in a heavy truck. But like the first responder said if youve done major mods small exhaust will choke the engine.
The stock down pipes on mine are somewhere around 2-3/8 od (strange I know), which is good for much more power than my stock motor makes. Dual 2-1/2 mandrel bent pipes with free flowing muffler should be good for close to 600hp at the flywheel. A single 3" is good for around 400hp or so, so dual 3" would be overkill unless you are planning on making over 600hp.
If this is a strip truck, dual 3" would be fine, but if street driven much, dual 2-1/2 would be plenty and would have a low to mid range improvement over the dual 3". Actually, 2-1/4 is probably sufficient until about 500.
If this is a strip truck, dual 3" would be fine, but if street driven much, dual 2-1/2 would be plenty and would have a low to mid range improvement over the dual 3". Actually, 2-1/4 is probably sufficient until about 500.
