CTmax02

iTrader: (3)

Intrested in buying WSP y pipe but was mentioned here that there was a loss in HP ? For people that felt increase how much HP do u think ? Thank You for any help I can't search

GreekMaxima

Look... i like my y-pipe and i feel more power (i feel MORE power after a week almost) because i have a friend with a 94 prelude (5spd, headers, catback and an intake) and i raced him with my 2k2 maxima without the y-pipe and he smoked me from the light (if i do race after 30-40 mph my maxima is rocket), when i put the y-pipe i raced him and finally i smoked him and now with a b-pipe i smoked him so BAD and he said me "damn your car is so fast now" friday and saturday will be rainy man... my next big mod will be UDP!!!

Donkey®

iTrader: (3)

UDP a 'big mod'? Anyways, there is absolutely no loss in power with a y pipe.

Virus

iTrader: (1)

I gained 5hp and 6tq from y and b pipes together.

MaximaMan77

How much of that HP do you think came from the B pipe?

2k2max

Strange....

I've heard of nearly 20whp gains with both??? Now I'm more confused..

Donkey®

iTrader: (3)

I think his dyno was not right. It is definitely more than that.

MaximaMan77

No that dyno was right on. 20+hp gains are on 3.0's not 3.5's.

2k2max

That's not what "Larry" had posted when he installed his Y & B. He's got a 2K2 and reported nearly 20WHP, but also did some intake modifications during each run...

MaximaMan77

Not only intake which is good for 10+hp but he cut the stock pipe off the muffler and had a 2.5" pipe welded on.
Virus's Y&B comparison is the closest we've got yet for a just the Y, which no one seems to want to do.

03BlkSETE

iTrader: (3)

I remember one other member who dyno'd less horsepower with a y and b pipe than with a b pipe alone. I believe he then removed the y pipe. I cant remember his name right now.

MaxSE2k

Well... I went into the dyno shop with these modes:
WAI, RT Cat & Cattman Cat-Back and dyno'd @ 218hp

I then went back in after installing the y-pipe (the only new mod), and dyno'd @ 216hp. I have since removed the y-pipe... Same dyno machine, same shop, blah blah blah. Someone else on here did the same thing, the shop suggested a AFC, they installed that, and were only able to get him back to where he was BEFORE the y-pipe...

Theory (again): the WSP design has unequal pipe lengths before the collector. There are several articles and a ton of research on the importance of equal pipe lengths. CM Performance and I are working on a y-pipe that has equal pipe lenths, but still having the increased pipe diameter. Unfortunately, due to availabillity of my factory y-pipe (which is on my car), the process is slowww. More to come...

03BlkSETE

iTrader: (3)

I'm not sure if this is feasible but as an option, how about a y pipe that eliminates the precats. It might be a good option for those that don't want headers or the hassle of removing headers for any possible emissions inpections. A y pipe should be easier to take in and out if necessary.

CTmax02

iTrader: (3)

Thanks everyone. Probably get a 2.5 b pipe first

MaximaMan77

Good choice!




MaxSE2k do you still have the WSP Y? If you do you could swap them out again and have the stock one in the shop as a template. I'm still not sure your going to gain much with bumping up the diameter and leaving the pre-cats in, but it can't hurt to try. Good luck.

MaxSE2k

What we're trying to do is have the two pipes side-by-side, and be able to test fit the new pipe as needed.
You're right, the pre-cats are still a major restriction. In performing some basic volume calculations from 7th grade geometry class - the two 1-5/8" pipes should be collected into a 2-1/2" pipe, not a 2" pipe - so the collector on the factory pipe is still another restriction. Anyones design that increases the pipe diameter before the collector is useless at this point anyways because of the precats. The benefit will only come from the collector being 2-1/2". To do this correctly without chopping the stock y-pipe, we need to replicate the design of the stock pipe (equal lengths again). So by increasing the downpipes to 2", we're leaving the door open for a future header installation that may have a 2" downpipe.

Me-> <-WSP

Chinkzilla

ooh, a performance mod for our cars utilizing scientific methods?!


I'm exited

Can CM do headers? I'm convinced 90% of the gain from the 4th/early 5th gen Y-pipes were from removing the pre-cats. Just look at Emax's numbers and you'll see.

MaximaMan77

Yes there is a good gain on those cars but it's not 90% just from the cats. Early 5th gens only remove 1 pre-cat and still show good gains. The angle at which the 2 runners comes together isn't very good on the 3.0L and creates back pressure. Cattman used to have good pics of this on their web site. So the after market Y's releived this back pressure and produced good gains. On the 3.5L Nissan made a much better design, replacing it doesn't help power much if at all.

MaximaMan77

Here is a good pic of the old style Y. You can see the bad angle I'm talking about.

Chinkzilla

Yeah, tubular headers would still be nice no?

:P

02MaximizedVQ

As much as I hate Stillen, I wish they'd hurry up with their Maxima headers. It would be nice just to have something that mates to the stock Y-pipe which removes the factory pre-cats.

A note about aftermarket exhuasts on a 2k2 Maxima. Its best to get a high flowing muffer when you install your B-pipe and you MUST get rid of that dinky 1 7/8" muffler pipe between the B-pipe and the muffler.
If you don't do these two things you SHOULDN'T see any gains.

Jesse

Chinkzilla

i gave up on stillen a long time ago

I honestly don't think they give a crap.

Maybe we can retro-fit the altima headers?

MaxSE2k

Not entirely true... an aftermarket b-pipe eliminates those very restrictive crimps... simply cutting out those crimps really should help things flow.

03BlkSETE

iTrader: (3)

I met the altima guy (snolden on Altima.net) and he believes the altima headers could be made to fit ours. Also he heard that the maxima prototype guy was still trying to get into hotshot.