Glass Packs

I have a 89 cherokee and am planning on changing the exhaust. Right now it has no muffler, about 6" of pipe behind the cat. Anyway, I am thinking about running a glasspack and have a few questions. The shorter the glasspack the louder it will be, correct? I am thinking about running a 8 or 12" long, 2.5" glasspack, would a 8" be too loud? I want to keep the low, raspy tone of no exhaust, but its Michigan and you have to have a "muffler" and pipe. Im gonna run a side pipe on the jeep, out in front of the rear tire. Yes, Im that 18yo kid down the road that pisses all the neighbors off with loud noise. I know someones gonna comment on it so before you even think about it, just keep it to yourself...

Thanks, and sorry for all the questions
Dylan

what motor do you have?

Hey man... I live in michigan myself and I have a glasspack on my truck which has the 5.7L v8 and I have a tailpipe on my truck an 8" would give a nice loud tone but when it comes to the raspiness it's all about where you put the pack. The closer to the motor your glasspack is the more raspier it'll be. It also depends on the brand the thrush packs are louvered and if you get a cherry bomb it's a strait thru design now with the thrush tubes if you install it with the louvers facing the engine it'll disperse the sound over a greater area and give you a low drawn out tone with little to no rasp in the lower RPM range if you install it with the louvers pointing toward the tailpipe it'll give you a more raspy tone throughout your RPM range. However with the bomber regardless of the install direction it'll be raspy throughout your range but the further away for the motor your pack is the lower the tone will be. Mine is installed with the louvers pointing toward the motor and is installed back by my rear axle and I have virtually no rasp until about 3500 rpm and is a very nice low roar when accelerating! Also the tailpipe you chose will play a part in the tone... A short tailpipe as you intend to install will add to your sound level the shorter the pipe the less resonating and the louder it'll be the longer the pipe the more resonation and the quiter it'll be!


So to answer you question in short if you get a short thrush tube and install it backwards with a short tailpipe then you'll have the loudness of no exhaust and the rasp that you want. Also if you really want some rasp if you have access to a torch then heat your pack up until it glowing and beat it a few times with a hammer and spray it with a hose and cold water and it'll break up the fiberglass inside the pack and give you the sound of blownout glasspack which would be tremendously raspy!!!



P.S. You darn kids with you loud butt exhaust why can't you just be like eveyone else why do you have to attract so much attention to yourself!!! haha Just messing with ya! Welcome to the site! hat part of Michigan are you from?

Quote :

P.S. You darn kids with you loud butt exhaust why can't you just be like eveyone else why do you have to attract so much attention to yourself!!! haha Just messing with ya! Welcome to the site! hat part of Michigan are you from?

Sanford, about 8 miles from Midland..
Also, the jeep is 4.0l I6, the 2.5l 4 banger and 2.8l v6 (only used in 86) is rare around here...

I have looked on summit racing site, and have found 4 glasspacks to choose from: cherrybomb 8", thrush 18", Dynomax bullet 12", or summit 12".

Here are the links:
http://www.summitracing.com/parts/IMM-87522/
http://www.summitracing.com/parts/WLK-24069/
http://www.summitracing.com/parts/WLK-24215/
http://www.summitracing.com/parts/SUM-630805/

Im thinking about going with the summit 12" or the 8" Cherrybomb..

Thanks, Dylan

Welcome aboard Dylan! Glad to have you.

As for your question I would go with the 8" Cherry bomb, nice rumble under power but still a quiet ride at speed.

Thats what I was thinking, but its close to 20 bucks more than all the others. Ive heard summit kills you on shipping, on top of that..

If your hurting for money, buy the cheapest one, but I can tell you from experience, you get what you pay for.

I use Summit all the time and can tell you there shipping costs are very reasonable, also IIRC all orders over $100 are free shipping.

Yeah, I might get the Dynomax Bullet, or Summit 12". I need to get a tach for it too, the jeep isnt on the road right now, So I dont have alot of money (no transportation=no job). Thinking of getting one of these, Most likely the Sunpro:
http://www.summitracing.com/parts/SUM-G2886/?image=large
http://www.summitracing.com/parts/SUN-CP7903/?image=large

The Jeep doesnt have a tach?

No, its not a complete idiot light cluster though. It has all the guages like oil pressure, water temp, etc. But no tach....

That sucks. I hate not being able to see RPMs. Luckily thay are pretty easy to install on Gas engines.

Yeah, seems to be pretty easy. Looks like all I have to do is run the tachs sense wire to the green wire on the coil..

Thats it. If its back lit you will need to run a power lead from the dimmer switch in your truck, and then need a ground.