Hey everyone. I have a H/C lt1 with some shorty headers( going LTs soon) no cat, and a flowmaster catback with an electric cutout.

The car seems to perform better with my cutout closed so I was thinking about taking mine off and giving it to my GF for her camaro.

So then I have my flowmaster muffler to go through and everything I read, everyone says flowmasters suck and are restrictive.

I've already got a 3in catback. So could I could just replace the muffler?

I'm not sure which flowmaster series I have. It's either 30 or 40 series and 1 inlet and 1 outlet. I'm not sure of the sizes but I'd assume 3in.

I'd like a muffler that would let me have dual tips, how would I go about that, just have a shop weld on the 2 outlet pipes for tips?

Could I put a magnaflow muffler on there, no problem? If so what's the part number for the magnaflow. Or even a hooker muffler whatever flows better. I'm not to concerned about loudness. I could always unbolt my cutout if I wanted it to be louder.

Sorry for noob questions. Thank you.

 

Sounds like it needs a little tuning

 

My friend got 10 more horses on the dyno with his cut out open then running through the restricting flow. But the flows sound great and quiet it down when needs to. When your ready to run it simple flick of the switch

 

LT1s like a little bit of backpressure

The Flowmaster single in/out 30 and 40 series mufflers flow just as well, if not better, than most other aftermarket exhausts. I went from the 30-series to Magnaflow and picked up absolutely no power

If you like your current system, I can show you where to cut the outlet for a dump and I have some brackets I made for dummy tips I'll sell for cheap

 

Idk, I suppose it could use finer tuning. I only have 1 mail order tune from madz28 since my mods. The car just feels like it has more torque with the cutout closed.

If my muffler flows fine how would I go about doing some dummy tips Vinr1?

 

It will feel that way mostly because of the loudness vs how fast your moving. I gained 10hp and 1 tq with cutout open vs closed.

 

Yep - the "lack" of power you feel is entirely psychological. I had similar results on the dyno with mine open versus closed - about 10HP.

 

I gained 6hp with my cutout open. But the car still feels more responsive with the cutout closed. Its not just WOT either, with it closed the car takes less pedal to go faster.

Feels similar to when I drove my 88 with open headers, car felt more torquey after the exhaust was connected.

Im assuming its because of the backpressure at lower speeds with the cutout closed that makes it seem more responsive, but with the cutout open for racing it would be better for up top.

 

You do lose a hair of low-end torque with an open-type exhaust but the gains up-top outweight whatever losses there would be.

 

Shoot me a PM

 

Looks good, but probably wouldn't look as good on a camaro

 

Yep - the "lack" of power you feel is entirely psychological.