jakeman711

I had a custom exhaust put on my box. I went with the stndard magnaflow mufler. I went with 2.25" pipe from the cat back. But, for the resonator they guy put a glass pack in. He told me I was the same thing as a resonator"straight thriugh". Is this ok? Or should I go back and have him put a resonator on it. I couldn't use the stock resonator because I went with larger pipe. And my box feels like it lost power. I t doesnt wind up as fast in the upeer rpms? What should I do. Thanks.

chadfo

You probably lost power because you don't have as much back pressure. Your exhaust doesn't need to be that open if you don't have a turbo or supercharger.

jakeman711

what about the glass pack?

chadfo

I'm no expert but I don't think it's hurting anything other than maybe additional weight.

I think you have 2 options other than replacing everything again.
1. Find something to restrict the exhaust flow a little to regain some torque. I think it would be great if they could find a valve that you could control. I know Honda put one on the 929 that would close at low RPMs to give more torque and then open at higher RPMs to let the engine breath and give peak HP.
2. Deal with it and get more power mods that will help utilize the extra flow.

I had a friend with a Mustang who said he lost a lot of torque when he put a high flow exhaust on. He ported his intake and was back in business again.

jakeman711

should I polish my intake. lol.... j/k. I am in the process of installing my zex system. I hope that helps. What do you think? Do you think a header would hurt me even more?

chadfo

I'm sure the Zex will help while you are spraying. I don't know about the header. Logically adding a header which allows for more volume and improved flow shouldn't hurt but flow and velocity in intakes and exhaust can be quite tricky. I don't have the knowledge to guide you there.

What I can share with you is that I put an Injen intake on my car and I noticed a little more power. I put the Borla axle-back on and after a week or so noticed a little more power at higher RPMs but lost some torque on the low end. I added a Strup header and gained a little more on the high end. I put on a Perrin pulley last week and regained some of my torque overall. The driving experience just feels better with more power.

If I were in your shoes, I'd go with the pulley first because it made the most significant difference for me.

jakeman711

I have the pulley already. I also have the Fujita SRI. I hope the zex helps. I am tired of being spanked by civics and caviliers!!

chadfo

When you spray you shouldn't have a problem with the Civics and Cavaliers unless they are packing.

oldboxman

I used to own a 929!!! Yep they put a valve in the exhaust that would run basicly a 4-2-1 then at a specific rpm or speed the valve would open up into a 4-1.I took it off and put an aftermarket exhaust on and just went one tooth down on the front three up in the rear to make the low end crazy.

jakeman711

Should I go in and have it redone with 2". I am getting the opposite effect I lost it in the upper rpm's. The lower rpm's I don't feel a difference. I don't kno wwhat to do. Please help!

jakeman711

huh? The magnaflow catback system is 2.25". I wonder what is up with that? They said they got 5 hp and 5 ft/lbs out of it. I am baffled.

chadfo

Read this. It might give you a better perspective.

http://www.geocities.com/MotorCity/7...usttheory.html

oldboxman

This is the reason I went with the 4-2-1-design of header and not the 4-1.You can easly loose power by going with more flow.