chris j vurnis

Hello:

For those of you that went to aftermarket Ypipes, can any of you comment on the actual "y" connection on the stock pipe?
Is the merge of the two cylinder banks on the stock pipe relatively effecient or did it look restrictive?

I was looking under my car yesterday but didn't get much of a good view of the pipe due to the heat shields under it.

I might have a local exhaust shop play around with that connection point if it proves to be a restriction --

Dan 93 SE

FYI,If you remove the heat shield you will find that the rear down pipe actually turns forward and merges into front down pipe against the flow of the exhaust. This is why I believe power is gained on aftermarket pipes, not removing the pre cats as some ascribe. For the price you will pay to mod the OE pipe, you might as well replace it with an after market one.

Dan WSP

breaux124

iTrader: (1)

You can look at the pictures here
http://www.geocities.com/breaux124/ypipes/review.html

You'll see both the cattman and the warpspeed.

It's the removal of the precats that creates the power. I don't think the merge at the Y will do much for you.

Dan 93 SE

Brian if what you say is true, then there should be no gain when converting the stock y-pipe on the 3rd gen to an aftermarket model since the 3rd Gen Max has no precats.Just ask the 3rd gen boys if a aftermarket y-pipe makes a difference. Think about physics for a minute. By switching around the rear exhaust down pipe, instead of entering the exhaust stream against the flow of the front pipe. It now enters the flow going in the proper direction, towards the cat, not towards the front of the car.This allows the engine to work against less pressure. Removing pre-cats don't make the bulk of gains from aftermarket y-pipes in my book.

Dan

Miguel97GLE

Hey Dan,
I see from you sig you are part owner of Warpspeed. Any chance of you setting up a group deal for your non-mandrel bent y-pipes? Budget sold quite a few on the last deal but I'd prefer to buy from someone more reputable. Thanks.

Miguel

Dan 93 SE

Miguel, I don't think we will for now.Our price at $195 is a pretty good deal.There is not much profit at $195. They come with the lined flex section, hence little if any of the "bees in a can"sound. The bending looks very nice and one needs to look close to see any restriction. We will be posting independent dyno results of comparing mandrel vs non-mandrel in near future. My guess is you gain almost as much with non-mandrel. BTW the price for a mandrel bent pipe is not that much more. Please check out our web site or call Dallas at our 1-806-801-9338 # for more details. Thanks for asking.

Dan WSP

breaux124

iTrader: (1)

Holy crap, your right. I never really looked close at the stock Y-pipe. Guess I was just under the same misinformation.

I also noticed that on the original stillen design the lower flange also comes back around, it seems like alot of extra pipe, and not a smooth air flow.
http://integra.vtec.net/geeser/megamax/ypipe.html

chris j vurnis:
Listen to Dan, I mean he does own a company that makes Y-pipes. Just fork out the few extra dollars, save yourself some trouble and get an aftermarket Y-pipe.

TILLEYS99

iTrader: (4)

breaux124 hey I finally got that y pipe on I had to get new O2 fittings and add 2 more and change the front manifold in order to use it since mine is a CA spec. I like it though it makes a decent difference and seems to give more of constant pull very noticable when my auto downshifts.

Dave B

Dan-

I've got to disagree about routing of the exhaust off the rear bank I've got Stillen's Y-pipe and they use the same design as stock (down, forward, turn towards rear of car). This is done to create a close to equal length design which keeps load equal between cylinder banks. This same design is used in the stock y-pipe. Dyno results clearly show that Warp Speed, Cattman, and Stillen pipes all make the same power in a 4th gen which shows that the ugly pipe bend in the Stillen flows just fine. IMO, it's clear that the precats are the biggest restriction in the Y-pipe. The 3rd gen Y-pipe doesn't have precats, but it is designed with equal length tubing. Honestly, I don't see how an aftermarket pipe would increase flow on a 3rd gen. The 3rd gen y-pipe might be ugly, but that doesn't mean it's restrictive. Many thought the stock rusty manifolds on the 4th gen were extremely restrictive until Don honed them out and Emax added true headers and we all realized the stock manifolds were perfectly fine.

....of course this is all just my opinion.


Dave

breaux124

iTrader: (1)

Wow I didn't realize you had a CA spec. Damn, that seems like alot of work to do. Glad to hear everything went well.

How did everything fit? Do you have any issues with anything hitting? When your car is in gear, is everything smooth or does it seem to drive rough?

The best place that I noticed the difference was at higher speeds. When you gas it at 50+ you can really notice the difference in acceleration versus the stock Y-pipe.

Glad everything worked out for you. How much louder is your exhaust now?

TILLEYS99

iTrader: (4)

It wasnt that bad tokk me about 3 hrs because I have access to a car lift at my parents garage, other than having to weld in fittings and changing the front manifold it fit perfect. It does seem to rub and shake around the center console only while moving though. I found the fittings from a friend of mine that owns a performance shop the ones he had were 304 stainless and cost like $10 a piece to have made from a machine shop If anyone needs O2 fittings thats the way to go cause they dont distort when there welded on like the ones that come on the pipe.

Dan 93 SE

Dave B, hate to be a nit picker, but the Stillen pipe you describe is NOT the same as stock. Look carefully at a stock 4th Gen pipe, if you pull off the shields you will see that I am correct. The angle that the rear bank enters the front pipe is actually angled forward. The angle on the 3rd Gen pipe appears to be even more against the flow. Just ask 3rd Gen owners about performance gains from a aftermarket pipe. Its the exhaust flow that makes the difference.Nissan must have made the flow like it is on the OE pipe to either decrease noise,increase back pressure, or some how help with milage???? All I can say is we are happy to be marketing a product that is dyno proven, 3rd and 4th Gen to unlease h/p at a reasonable cost. I do agree that the pre cats do cause some restriction. No flame war here, just want to inform.

Dan

Dave B

Dan-

I still respectfully disagree. I friend of mine had a 92 SE and I saw his y-pipe and I've got the shop manual which shows the pipe. I don't think there's much to be gained. Bryan (the owner of the SE) probably had the quickest 3rd gen in the org (14.4s NA and 13.8s with NOS). He fully believed that the stock Y-pipe was perfectly fine. Coming from a guy that did some pretty amazing things with a 3rd gen, I believe him when he says the 3rd gen y-pipe is fine. However, this all just my opinion. What kind of gains do you guys see with these pipes?

BTW, I'm friends with GuidoSST(Dave) and I would be more than willing to test out equipment for you guys if you need donor cars. Unlike Dave, I put my mods on the day I get them and track test them that week


Dave