from the midpipe back....

['94ChickStang]

.....my tubing from the midpipe back in my exhaust setup is still stock and the Flows are welded in. What do you think I'm losing in hp if any? I'm currently putting 289/318 to the wheels (which could be better with a better tune imo)

 

[Dino Dino Bambino]

The stock dual 2.25" pipes will provide minimal restriction on an engine making up to 400hp at the crank (350rwhp), so changing over to 2.5" piping will probably gain you almost nothing. It's more important to have less restriction at the front of the exhaust system where the gases are hottest and the flow velocity is highest. The gases cool as they travel through the system and their volume decreases, which means that by the time they reach the rear half of the system they can occupy a smaller diameter pipe without adding any more backpressure.

 

[94-302-vert]

I have to say that I think you will gain a little by upgrading... I noticed a slight gain over welded in flows when puttin gon the 2.5" flows with dumps...

Are there better bangs for the buck, absolutely... But if you get a good deal on a used catback it is worth it...

 

[final5-0]

I like to relay this info from time to time

Several years ago there was a guy on these boards who had a 347 Stroker
with ALL the goodies.

He was running the stock OEM catback.

He went to an after market catback.

He had a good, reliable, dyno info that showed a gain of 10rwhp

My reasoning says he flowed a good bit more airflow than a 302
soooooo
Typical 302-306 combos are not gonna gain as much

Grady

 

['94ChickStang]

good info everyone, thanks

I'll move it down the list then...probably until the flows I have on there are dead

 

[Bosko5.0]

I love my stock catback. It makes more torque down low then when I have my cutout open.

 

[94-302-vert]

I changed mine jsut because I wanted LOUD... I wanted to be able to hear it on the highway with the top down, so when I got a good deal on these dumps I jumped on them...

 

[final5-0]

good info everyone, thanks

I'll move it down the list then...probably until the flows I have on there are dead

I think that is a wise move if you are focused upon making more power

Those pipes are not restricting the flow much at all

Grady

 

[mo_dingo]

.....my tubing from the midpipe back in my exhaust setup is still stock and the Flows are welded in. What do you think I'm losing in hp if any? I'm currently putting 289/318 to the wheels (which could be better with a better tune imo)

IMO the only worthwhile increase in the exhaust dept. you will actually notice would be to ditch the cats. Other than that, I wouldn't mess with it.

With all your engine mods, I think you are pretty close to maxing out your NA HP potential. Plenty of zing, you might want to work on the bling now

 

[final5-0]

I was kinda wondering about a couple things

Did you ever find the cause of hitting a bump and loss of power

Did you ever post up your pull after getting things sorted out

Grady

 

['94ChickStang]

naw I've brought the car to the shop 3 times since I got the car back (and again soon) due to it's excessive oil burning! They continue to prove their lack of giving a shi+. It's not burning as much as it was after some vacuum rerouting but my separator still fills quickly, I get a good puff of smoke starting the car after sitting for a while and I get blow by when I get on it hard.

The shop is still working on it for free but it's clearly a low priority

I haven't figured the cutting out but also haven't had it happen in the last couple weeks so the mechanic can't replicate the problem.

I haven't posted my pull yet because I hate knowing 289/318 is low for my combo so I was going to wait until the cooler weather comes to get to a new dyno and have it retuned/repulled. He still has it running a little fat imo




EDIT: But I'll stop being lazy and post the dyno sheet soon!