Finished my header today. It's installed and the car runs great. I drove it around for about 30 miles to let the engine learn, and then played a little bit. Throttle response is MUCH improved. Also, the car pulls a lot better after 4500 RPM than it did before. I have a dyno appt. for tomorrow at 8 AM (6/27/02) and will post the results later tomorrow after work. Pics will take a couple days as I don't have a digital camera. Have to take the pics, get them developed and put on CD ROM and find a place to upload them to.

 

so i guess your butt dyno says there was definite improvement.

 

in a previous post you said you were thinking about producing these right? if you are still plannin on doing this do you have a price in mind? also does it knock out the 1st cat? is it a direct bolt on for the 2002 P5?

 

And the dynojet says... the butt dyno was right! I'll compare the run to the last run I did last time I was in. I also finally figured how the whole correction factor thing works. The HP and Torque figures are the actual numbers put down to the rollers on the dyno. You have to multiply those by the correction factor to get actual numbers. That would explain why I was getting slightly lower numbers than most people at stock and close to stock when I first dynoed it. The correction factor then was pretty small, but it would have made a 2-3 HP difference which would have put my car close to several other people's cars stock. It was warm outside today (82 degrees and 27.94 in Hg) so the correction factor is up to 1.07. That means I take the dyno figures and multiply by 1.07 to get the corrected numbers. Last time I had it dynoed it was only a 1.03 correction. The numbers I posted last time were uncorrected.

Anyway, the big news is that there is no loss of torque down low. It's about the same as stock until 3250 RPM, then it pulls harder the rest of the way up. Max gain was 7.8 lb/ft at 4250 RPM with slightly over 119 (uncorrected) compared to 111.2. Torque falls off slower also. It made 3-4 lb/ft more through the rest of the RPM range. It keeps pulling longer also instead of falling off at 5750 RPM.

The power is slightly higher than my last test up to about 4250 RPM then it pulls away with a max gain (uncorrected) of 5.4 HP at 6250 RPM (113.4 HP). The HP keeps climbing all the way up now instead of tapering off at 5750 RPM like the last test. I have to do some checking to see how the whole correction factor thing goes. But the car is putting down quite a bit more than it was back around the middle of May. It put down approx 108 HP and 112 lb/ft of torque max last time uncorrected and the correction factor is larger this time due to air density.

 

Just got off the phone with dynojet. The numbers on the dyno sheet and on the graph are supposed to be the corrected numbers. Note: supposed to be. I've spoken with other places that say that there will be a several HP difference between dynojet dynow.

I definately gained some. I started with 101.8 HP peak and 109.2 lb/ft with the J spec intake and exhaust cams. I have a larger cat back, a custom header and a better intake now and have 113.4 HP peak and 119.1 lb/ft of torque. Plus it revs nicer and pulls longer. Still, I need more! Next up, Eaton supercharger.

 

Did you remove both cats or are they in the place?
Next you should try the pistons , then we others know what are these about

But keep it up man Nice info!

 

Good job Traveler. Ain't building a header fun? I've got a lot of resect for someone that takes on that task. Give yourself a pat on the back.

You didn't by chance check exhaust gas temp did you?
I'm curious what it's running with a header, cuz it'll give a good idea of how optimized the ignition curve is given the stock fuel map. I assume both cats are now gone.

I'd also like to suggest you work on a programmable ECU before you go with boost. It seems like the next logical step for someone who likes challenges.

 

Actually, I retained both cats. The primary cat has the exit opened up from 1.71 to 2.05" with a 2.25" cat forward pipe. As for building an equal length short header in that much space, you ain't kidding about it being a lot of work. I maintained 20" average length primaries. 19 1/2" shortest to 20 1/2" longest.

No exhaust temp but we did notice that it leaned the over rich condition that we had before. Now it doesn't get too rich until 5250 RPM. Before it started getting really rich at 3500. The ignition map is seriously slow. It would be perfect with boost but it just isn't optimized for normally aspirated.

I'm thinking about Unichip again but I'm not sure that it will give me as much control as I want. It will control WOT and it will bump up the ignition a bit though which is what it needs. I want to go supercharged so I'm thinking that I'll leave the stock ECU in place as the ignition map is good for boost. Then I'll just run an AIC and a couple extra injectors to richen it up a little under boost.

By the way, the header fits everything including the EGR fitting. The 02 sensor is almost in exactly the factory location and the only thing I had to remove was the factory lifting bracket between the #1 and #2 ports.

 

Sounds cool Traveler...Good job.

 

do we have a price ballpark?

 

Well, I'm still not sure if I'm going to 'produce' these or just make them on a as requested basis. I don't have the equipment to ceramic coat them nor do I have the ability to buy the parts in large enough volume to get the prices for the parts down much. Right now I'm into the one I just made for about $380 but that includes the heat wrap I'm using to keep the underhood temps down. The machine shop that I can get the flanges from will cut the prices on the next flanges I make now that they have a template and know how to cut them. However, it's still an expensive piece to custom fabricate. I've got about 9 hours into this one but can do the next one in 5-6 I'm sure.

Also, my welder isn't the greatest. The wire speed keeps surging so I have to get a better MIG to make the kind of production welds that I'd feel comfortable selling to a customer. I'm selling a pick up and some of my car parts from my last project over the next couple weeks, so I intend to upgrade. I'll keep you posted when I feel I can turn these out and what the price will be.

I'm checking into coatings over the next couple weeks also to see if I can't have these coated for a decent price. I'm trying to make them look good and make them so they will last. This first prototype was just a 'proof of concept' to make sure that it made horsepower and torque. It does, so I'll try to get on the road to production over the next few weeks.

 

You stayed 'clean' AND upped the power!!

You may have even outdone Racing Beat ....they fabbed/fitted a header for the MP3; but all they say about testing it is that they 'found the 1st cat to be a power robber'.....i'm sure that's true, but you've proved that you CAN make some nice power EVEN WITH BOTH cats.

 

If ever you decide to go into production, let me know.

 

I'm in the process of building another header with a few slight improvements. Mainly addressing head flange bolt access. Also, this one will be ceramic coated. I'm trying to get the admins to reply to some PM's so I can get authorized to even offer them for sale on this site. Once I get the O.K., and once I feel comfortable with the quality, I'll probably start offering these for sale. I'm checking into design protection also so I don't get burned.

 

I'm 90% done with the next header. I'll be sending it off to be ceramic coated probably tomorrow. Should have it back next week and then I'll post some pics. The bolt access is much improved over the first one I did and the welds are better thanks to my new welder. The bolts can almost all be accessed with a socket/ratchet. there will only be a couple that will need a wrench. Should be much easier to install than the first one I made.