bsowa

What are the benefits/drawbacks of a test pipe, High Flow cat or just gutting my current cat?

Where can I find a test pipe...what are good high flow cats and mufflers?

Richard Cooper

bsowa,
I use a test pipe in my 1981 coupe and it works great. It made the mufflers sound much better and they are not to loud. It took me less than 20 minutes to install and fit perfect. I got my test pipe from http://www.mufflertech.com they are in California. It cost me $39.00 shipped to my front door. It also comes with all new nuts and bolts. It took 4 days to get to New York. I kept my old converter just in case I need it for inspection, 20 minutes and its back in. Just used some high temp RTV on the flanges and you're set to go.

bsowa

Awesome...Does the test pipe add noticeable HP?? Does it increase dramtically on fumes/smell?

Any suggestions on mufflers???

tnt76vette

I noticed a small difference when I put on my test pipe.......But if ya really want to notice a difference, go to true dual exhausts.....then you will notice some real HP gains......... :yesnod: :yesnod: :yesnod:

Richard Cooper

bsowa,
There are NO noticeable fumes or smell from the test pipe. As far as HP I am really not sure if there is any more power gained from the test pipe. I think I feel a little more pep, but it could be just because I want to feel more power. It sure did not hurt anything. And I really love the sound it made my vette growl a little.

Ryan77

Another vote for true dual exhaust, that's the only way to gain real hp. A balancing pipe is also a very good idea, like an X or an H pipe, and is strongly recommended by Flowmaster. As far as a good muffler, Flowmaster and Borla seem to be the best, but Borla tends to be more expensive. I bought Flowmaster 40 series, an X pipe, and Hedman headers, but don't know how well it works since the headers are backordered :mad . If you do go Flowmaster, you'll have a lot of choices. The 30 series are race type mufflers (very loud), 40's are a little quiter, 50's even quiter, you get the idea. Also, you can get their mufflers in regular or delta flow form. The delta flow option on any of the series is supposed to scavenge exhuast a little better, cut down interior resonance, and give a couple more horses (probably unnoticeable in that respect). The regulars are just a bit louder and don't scavenge as well (again, probably unoticeable). I wanted sound, so i bought the regulars, and will let the X pipe scavenge for me (balance pipes create a suction). Don't get me wrong, regular Flowmasters are a very good high performance muffler, the delta flow is just supposed to be a little bit of an improvement. Sorry for the rant, but I've done a lot of research on exhaust and looked at many dyno sheets.


[Modified by Ryan77, 8:20 PM 8/5/2002]

NHvette

Thanks for all the info, Ryan - certainly not a rant.
Now, I want an X pipe installed - well whenever it's all back together.
:seeya

bsowa

So....how much to put in a true dual with flowmasters, x pipe, and no cats (will have to buy them to put in for inspection though)

How hard is this job also....welding involved?

KENS78SILVERANNIV

Just installed a new high flow cat today... It made a world of difference... better flow and much better sound from the mufflers!... Plus the car stays smog legal. Go for it! :cool:

Biker

I have both a high flow cat (for Illinois emissions testing) and a test pipe I purchased from Muffler Tech (http://www.mufflertech.com) in California. I can honestly say there is no difference in performance with either device. The test pipe offers a little better sound and less heat, but that's about it. I don't want to install true duals. With the exception of a K&N air filter and the straight pipe, my '81 (4-speed, 30k miles) is 100% original and flawless. It's a painful decision because the car is somewhat slow in stock form. But that's the way I want to keep it.