I haven't said anything about this project because I wanted to do the testing first, but I'm quite pleased to report that I've put a beautiful set of prototype headers on my 97 Maxima and they make some pretty good power. And they sound incredible!

Here's the basic information...

Test car: 1997 Maxima 5 speed, 103,000 miles on a well used engine that's a little weak and a bit past its prime (as indicated by its relatively low "before" dyno run); baseline measurements taken with a JWT intake, Cattman Cattback exhaust and a stock Y-pipe.

Baseline run w/ stock Y-pipe: 167.5 max hp @ 5000rpm; 182.6 max torque @ 4000; avg hp 132.2 from 2300-6100 rpm; elapsed time 10.32 seconds from 2300-6100 rpm

Run w/ prototype headers: 183.9 max hp @ 5000rpm; 197.5 max torque @ 4600; avg hp 143.1 from 2300-6100 rpm; elapsed time 9.83 seconds from 2300-6100 rpm

Although the difference in maximum hp is 16.5 (about 20hp at the crank) and in maximum torque is 14.9 (about 18 ft/lb at the crank), the largest differences between the two runs are 18.6hp @ 5400rpm (about 22.5hp at the crank) and 18.5 ft/lb at 4800rpm (about 22.4 ft/lb at the crank).

I'd also note that the "average horsepower" is a very useful comparative figure. You could have a modification that spiked the power at upper rpms but not have a large effect on horsepower across the rpm range. These headers increase the average horsepower by 10.9, which is a BIG impact that indicates that the increases in power occur significantly across the entire rpm range, not just in some concentrated range.

Based on my experience, figuring all other things being equal (and noting this is a very well-used engine, burns some oil, etc.), I'd say these headers make about 25% more power than a performance Y-pipe.

I don't know what the price will be for a set or exactly when they'll be available. They'll be somewhat more expensive than a Y-pipe, but not a lot because they will probably be made from mild steel (rather than stainless) to keep the cost down. Given that my set took an experienced mechanic about 6 hours to install, installation will obviously be more expensive.

Oh yeah, the sound... These aren't louder than a Y-pipe, but they sound sweeter due to the equal length primary and secondary tubing -- much more melodious and without the slight harshness in tone that Y-pipes have under heavy accelleration. I'm not kidding, it really makes the car sound cool.

I have a typical DynoJet graph as well as the table printouts (at 100rpm intervals). Also have an Excel spreadsheet containing the two runs for analysis purposes. Will be happy to send copies to any who inquire (contact me directly at bcatts@xtra.co.nz).

No chance to look into this yet, but these headers should be useable on the 1999-2001 CA/NLEV engines too, though it may be necessary to add an exhaust sensor someplace. It not impossible that they might work on the VQ35DE too, we'll see.

Brian C Catts
Cattman Performance

 

The problem is you need to have an aftermarket y-pipe so we can see how it does with the headers. Cause most people have y-pipes they want headers that will improve the horsepower not have to buy headers that will replace a y-pipe which meant that we wasted out money.

 

Sounds like another VQPOWER special

 

And Cattman performance does it again. Thanks guy.

 

Thanks for the info., Brian. Just so we're clear on the gains between your baseline & the "Run w/ prototype headers. . ."

Were you running with the same "stock Y-pipe" when you ran the prototype headers, or did you throw a Cattman Y-pipe on there?

This key factor is important for an accurate interpretation the data.


EDIT: HEADER REPLACES BOTH THE STOCK MANIFOLD AND Y-PIPE according to Cattman


Thanks for continuing to develop new technologies for the Max!

 

The place to start is checking against stock. I took off one of our older Y-pipes to put on the stock unit for baseline checking. Didn't want to foul a new Y-pipe just for the sake of a dyno.

Point well taken though, because how well the headers do against a performance Y-pipe is the second question. My estimate of 25% better is a reasonable one, based on considerable experience and observation.

Given this is on a weak engine, the % increase is probably a better comparative measurement. Increases from 4800rpm on were about 11%. This is significantly more than I've ever seen come from a Y-pipe test on any engine -- given the existing modifications, I would expect to see a Y-pipe add about 8%.

Brian C Catts
Cattman Performance

 

Ah, key point indeed, sorry for not being clear. These headers run from the engine block to the catalytic convertor. They replace the exhaust manifolds AND the Y-pipe.

Brian C Catts
Cattmaqn Performance

 

OIC, I'll edit my posts to avoid spreading confusion. . .

Thanks for the clarification.

 

Sounds great Brian. Set a price and start production. So this is just exhaust manifolds right? Not exhaust manifold + y-pipe?

 

Awesome! I would like to know when these will be available? Do you want me to test fit them on my 2002 Brian? You know I am good at testing your prototypes Drop me a email at emax1995@yahoo.com and we can set this up if you would like. I am 100% confindent I can bolt these on my 2002 and supply you with pics and a how2.

 

Wow! That sounds awesome. Want me to test fit them onto a VE? Since they are the same as the VQ...

 

Does this mean they wont fit a 2k fed spec?

 

Sounds good Brian. How long before these are in production?

 

Good question. The two manifold pieces do what the stock manifolds do, bring the primaries together into a collector. The secondaries replace the Y-pipe, running from the headers to the catalytic convertor. The header sections can't be configured properly if a stock Y-pipe is used.

If there's a "good news, bad news" aspect to this, its that the headers work great, but can't be used with a Y-pipe (stock or performance).

Brian C Catts
Cattman Performance

 

No, they should fit a fed-spec without any question, as is, though it might be useful to weld on a bracket (the added bracket is the only feature that distinguishes the 1999-2001 Federal y-pipe from the 1995-1998 Y-pipe). I suspect that for them to work on a 2000-2001 CA/NLEV it will only be necessary to add an O2 sensor.

Brian C Catts
Cattman Performance

 

This sounds great. I'm glad to hear that someone finally developed headers for the Max. I think that someone who doesn't have a y-pipe would have a hard time turning down these headers. I however, already have a y-pipe and I think I'll be hanging on to it for quite a while. I don't think I could justify forking out some major cash (probably around $350-$450) for a few extra HP. 25% of 15-20HP is only an extra 3.75-5HP. I think a dyno comparison btwn an aftermarket y-pipe and these headers would be very useful. Thanks again Cattman for continuing the development of the Maxima aftermarket.

 

Do you have any idea as to when these will be available?

 

See original post - he said he's not sure when.

 

Please keep us posted

 

Good job, Cattman. It's about time someone developed a good set of headers for our cars. Hopefully they will truely give more power at all areas. Did the shape of the power curves change at all or were they just elevated. The front manifold is cake, but that rear manifold is scary


Dave

 

Sorry. I wasn't real sure what he meant by that.. but, please do keep us imformed.

 

GREAT! You all at Cattman amaze me with all of the new products you keep coming out with. Be sure to make alot because you will get alot of orders for them. Cant wait till they are released

 

Brian, any way you could to a comparison dyno run on the same car, but with stock exhaust mainfolds and one of your Y-pipes?

 

Here is the dyno Right click and save as or cut and paste.

http://www.geocities.com/nismo87se/d...attmanDYNO.jpg

 

Assembly allows for flex section as well right?

 

I can see the value in what you suggest, but I'd have to take the header back off and replace with the Y-pipe to accomplish that. That would be another 7 hours of labor and I just can't justify it since I don't do this kind of wrenching. I would have done that in the beginning (the process started with a performance Y-pipe on the car) but the pipe on my car was an old one that pre-dated our current design so the results wouldn't be that meaningful. I could have tested with a new one on, but my time in the States was very limited and it required putting on a brand new Y-pipe just to do the test, and then taking it back off to put on the headers (thus reducing its value by about a third). Just didn't seem worth all of that.

Nothing accurate or scientific about it, but as I recall the last time I dynoed this car with Y-pipe etc., it made about 178 hp to the wheels. The engine was a little weak then, and moreso now, so it would not be unreasonable to compare the difference as about 176-177hp with the y-pipe and 184 with the header.

Brian C Catts
Cattman Performance

 

I'll pass that along as soon as its apparent, but I'll need to confer with the developer next week. I'll pass the timing and cost along as soon as I know more.

Brian C Catts
Cattman Performance

 

You'd be welcome to buy a set and try them out, it would be so cool if they fit the VE30DE too. ;-) Remember that they not only have to fit to the engine, but the outlet end needs to be positioned exactly where the end of your Y-pipe is now.

All of that said, however, I just remembered that the company that developed these also makes a version for the A31 (gen3) but that may be for the VG30E.

Brian C Catts
Cattman Performance

 

Wow, great memory. That said, however, I would stress that this test really wouldn't be comparable. Not even the same car.

Based on the age of this engine, other previous tests, etc., I still stand by my estimate of a 25% power advantage over what a Y-pipe will do.

Brian C Catts
Cattman Performance

 

The A31 platform never came to the US, the 3rd gen Maximas are based on the J30 platform. Exhaust routing is going to be totally different as the A31 platform was FR and designed around an RB-series I6 engine.

 

The headers raised ouput across the ENTIRE rpm range, which was the point I was trying to make when I discussed the gain in average horsepower. I have seen few, if any, performance parts that have such a comprehensive impact on power throughout the rpm range.

More power, everywhere! Apart from the actual testing, I can't remember the last time that my butt dyno was so impressed. ;-)

Brian C Catts
Cattman Performance

 

I understand completely, but suspect that someone out there will decide to upgrade and hopefully we can get one or more before/after comparisons done with a late model Cattman Y-pipe on the before measurement.

Remember, there's always a strong after market for used performance parts! ;-)

Brian C Catts
Cattman Performance

 

Thanks for the correction, but the mistake may be mine. I remember quite clearly that they did extractors for the gen3 so its likely that I erred in referring to it as the A31 rather then the J30. I can clarify this next week.

Brian C Catts
Cattman Performance

 

The more the merrier.

My only concern is installation, that rear manifold looks like a whole new world of bleeding, cursing, and busted knuckles.

 

let us know the pricing!!

what would be the size of the piping that would 'replace' the Y? any options for boosed people?

Good work!

 

i would love this... this will help .."un cali spec" the car..


let us know brian

 

Brian will this be the top and bottom part of the header, or will you have to use the stock y-pipe. I got confused on what you were saying. I don't get why you could not is an aftermaket y-pipe. So you replace everything. I mean theres companys that are making headers for Maxima, will they show the same results. I mean that one guy bought headers from new zealand and gained one horsepower. What did you differently to gain 10 horses more.

 

Interesting that you decided to make a setup with the Y built-in. I think this is generally how most header setups gain the most power, but especially for the maxima. Just replacing the headers does nothing according to what people have done with the NZ headers, so I'm not sure what the point in having headers-through-Y is, unless I see a comparative dyno. It may be that the headers really don't need to be upgraded with the stock engine setup...but a dyno would indicate this.

Very cool that someone came up with a prototype though. I would definitely want to see the header plots versus Y pipe plots of course.

Thanks for the informative post and testing though; definitely cool to test!

 

Are these Prestige Performance headers?????

 

Unofficially speaking, these headers look to give a 6hp-8hp bump over a performance y-pipe. That's not to bad. Looking at the dyno the gains on the top end are excellant. I bet with a variable intake manifold that you could see higher gains past 5k rpms. I know the supercharged guys are going to love this!