pmihaltian

What is the best performing high-flow cat for an L98 engine?

BADDUCK

I removed my pre cats and installed a Magnaflow (Carsound) high flow main cat. Quite a difference. I guess it depends what you mean by best performing.

WW7

I have the Magnaflow on my 89 with headers and muffler eliminators and the car sounds great.. According to there advertising the Magnaflow is 30% more efficient then a stock converter.Should be able to pick one up for about $150.00 - $180.00 ....WW

c4zf6nut

I guess you don't have emissions.-)

Where do you connect the Air pump then?

I understand our cars two precats and a single main cat, right?

Air pump should connect to the two precats only on start up. I want to keep the original setup, but would like to remove restrictions. I also do not want to pollute!

Ordered the Corsa mufflers, cannot stand the drone of the muffler shop hackjob. Mine sounds like a tank when lugged.

I am also interested in the best option.

pmihaltian

Thanks guys. I have eliminated my front cats and am running a DynoMax replacement cat. I also run muffler eliminators when I am not showing the car or having it judged.

Do you know if the Magnaflow replacement cat the same for all L98 engines ? Also, how might I find out how much better flow the Magnaflow might have over the DynoMax?

pmihaltian

The air pump connects to the main cat not the pre-cats. You can eliminate the pre-cats and replace the main cat with a high-flow performance cat and still meet federal emission standards. The air pump will connect to the replacement cat just as the OEM model did, but a good performance cat will flow at a higher rate thus having less restrictive air flow.FWIW.

WW7

According to there site Dynomax is also a high flow cat, so I wouldn't worry about changing over , there to close to call..You change your exhaust over for a car show?? That's a lot of work for a show isn't it?....WW

c4zf6nut

I think pre-cats are lighted up during warming up to control emissions.

How about the Magnaflow pre-cat (Y pipe) and main cat?

http://www.autoanything.com/exhausts...0A3369959.aspx


or I could get muffler eliminator/main cat

http://www.autoanything.com/exhausts...0A3039271.aspx

pmihaltian

Thanks WW. I think I'll stick with the Dynomax cat. Frankly, when I look at the photos of the Dynomax and Magnaflow high performance cats, they both look pretty much the same to me. Wonder if they are made by the same mfgr ?

When I have the car judged by NCRS and/or AACA I simply unbolt the rear Y-pipe and the two muffler hangers and drop the y-pipe/muffler assembly down and out. I have a second Y-pipe which has Euro tips welded on to it. I just slide it in place and bolt up the Y-pipe and the two tip hangers. With ramps or a lift, its a pretty easy & quick job (5 bolts total).

WW7

Cool, sounds like you have a great working quick change system To answer your question, from what I see about the companys, it looks like Walker owns Dynomax but Magnaflow is still owned by Magnaflow..WW

Tony A.

I got this "Tell a Friend" coupon the last time I checked out at AutoAnything.com. Use this link below to save you 15% on your purchase and it gets you free shipping. For this big of a purchase, that's $$$$! Hope you can take advantage and save!

http://autoanything.extole.com/a/clk/CvSLL

GREGGPENN

In general:

Metallic cats flow more than ceramic. (cost more too)

Cats with less "cells" per inch flow more than higher cells.

Cats don't come with/advertise flow data -- so determining which flows best would require both units and a flow bench. (People here haven't and won't do that due to the cost. Plus, people that care THAT much about cats use Random Tech or nothing at all.)

Deepa

I have the magnaflow on my 91.. Cheap and bolted up perfectly.

TJM

Random Technology has a good product.

c4zf6nut

I will probably go with Magnaflow. I see the same "high flow" cat at Advance Auto for the same price. (93441) Advance has a few coupons making the deal sweeter than AutoAnything.

They also have a "performance cat", MagnaFlow Direct Fit Catalytic Converter, Off Road Use OnlyPart No. 93941 I wonder if it has any advantages compared to On Road use. For me, I can remove cat if I want to, but I would rather use a good Cat Converter so I don't pollute and exhaust does not sound funny.

I see they have Walker and Bosal direct fit cats, which cost more money. Any advantage of either compared to Magnaflow?

Since I will have a muffler shop do this, is it a good idea to get a generic MagnaFlow cat for $67 and save money? Walker has a generic with AirTube but Magnaflow seems like it does not.

While we are at this, it seems to me that Advance sells mufflers (Flow Tech), which are single outlet, and then muffler tips to convert it to dual tips. For my 89, the local TUV inspection failed the car after they banged on the muffler, and there was rattling inside. The muffler was not leaking, was not loud, but unfortunately tough state inspections (TUV) are crazy.

The muffler shop built custom mufflers with dual outlet mufflers, and chrome tips, and charged me something like $400. Compared to the originals on the car, the mufflers are louder, but seem like more free flowing. They are unbearable like exhaust gasket leak when engine gets loaded.


C4ZF6nut

Kool88vette

Carsound makes a good cat at a good price.

cumbercr

I went with Random Technology. Got it from TPiS.

GREGGPENN

Try again...
http://www.magnaflow.com/02catalytic...niversal=94019

Plus, there are exhaust shops that can add a fitting for an air tube.