I just did an install on a set of Alphawerks headers on my G35...before I go into the driving let me just give you the numbers...average is all three alphawerks pulls averaged, less the average of the baseline pulls...the best is taken by comparing my best alphawerks dynos and my worst before dyno and the worst gains are done by comparing vise-versa...the average is the only real world number I believe that anyone should go by...

DYNO NUMBERS
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Average WHP gain: 17.64 whp
Average TORQUE gain: 16.40 lbs/tq


STATS ON MY CAR AND DYNO
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Automatic G35 w/ 20" Maya Multi-Piece wheels lowered w/ Tein Springs
Dynojet Dyno
89 degrees average temp for all runs
Humidity 24%
All runs at same engine coolant temp.
No fans allowed in front of the car.
Three baselines...install...then 3 pulls with headers (actually 4 pulls but one came out with an error)
SAE Corrected

Basically I wanted to make sure I was getting what I was supposed to for the money I paid for the headers. I wanted to make sure that there was no fan to force air in front and no playing with the engine temperatures so we made sure the car was run at the same engine coolant temperatures and all this done in one day to make sure the environmental factors were all constants.

As for the ride, first there is no check engine light problem and I have driven the car about 500 miles...the car feels like it keeps pulling alot more once it hits 5000 rpm. I felt a difference in the entire powerband, but that is were it was really noticable, especially at high speeds. It basically pulls at 80mph like it would pull at 65 before I put in the headers. As for the noise, the headers sound alot like stock since I have a stock exhaust. I guess that when you really hit some high revs you can hear a very small difference, but it is definitely slight. Next up are going to be the Alphawerks test-pipes hopefully sometime this month and I will post dynos again...

Hope this illuminates on these headers. If anyone has any questions just let me know, and thanks to all the guys at Nexus Industry: Victor, Anthony, and Carlos especially...who were helpful especially after I tried to to the install myself and failed...


MY BASELINE DYNOS 1+2+3
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:



ALPHWERKS HEADER DYNO RUNS 4+5+6:
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Looks good. Do you have a graph where the pre and post are on the same plot?

If you have the dyno data files, can you email them? ajlin_ek@yahoo.com

 

Is it me or are those baseline numbers low?
My numbers looked like that on a mustang dyno.

 

It is possible. My baseline was 219 with a Z-tube. Add on 20" rims, and there you go.

Dyno files?

 

Do you have plots for the A/F? And why is your pre-dyno based on MPH on the x-axis when the after dyno is based on engine rpm?

 

Yeah, 20's are a killer.

 

coupeondubs thanks alot man i had these questions in my head about these headers now i really want them by the way do you own a coupe or sedan cause it doesn t indicate on your first post. and good luck with your test pipes man!

 

Who sells the headers and how much?

 

Hey guys...first I bought the headers locally for $825...but a buddy of mine got them from avalonracing.com for like $675...Yeah I wish that I knew about them before also...but anyways what can I do.

Also my car is a coupe. I have posted my ride here before to get reviewed and now I also have the front lip on the car, but besides that it is pretty much still the same on the outside.

As for one dyno on the speed and the other on rpms, that is my fault because when they did the dynos they were showing me how the maps looked different ways and when I printed them out I forgot to put them both under rpm or speed or vise versa.

Besides that its been over 1000 miles, no check engine light and 1 pissed off porsche carrera owners on I-75 the other day

 

oh yeah, as soon as i do the test pipes I hopefully will post here also, but I am a little short on cash now for the parts and install and the dyno...

 

Your number may also be low because you didn't use a fan. When driving at high speeds your car will get more air and you should net higher numbers....along with your 20's you might be around 227rwhp stock and 244rwhp with the mods. Not bad at all, though I may be off some, I didn't realize headers made that big of a difference for our cars.

 

Pre #'s do seem low, but there are plenty of explanations for that...what's important are the numbers gained between the two runs...nice gains...how would this affect supercharged G's?

 

Gains would be less than installing a 9 lb. pulley and the pulley would be a fraction of the cost. Either way, don't forget to factor in the re-tuning.

 

Yes, this is true. But there are flow bennies to the headers that the pulley can't get me...my goal is to have a GREAT A/F across the board without compromising my internals...not necessarily the highest HP I can acheive. I was considering going with a motordyne spacer and headers to see how it would affect my A/F...

 

Randy G,

Just installed the Alphawerks Headers yesterday. Wow, a big difference thorughout the rpm range, but huge at the top end. Very well constructed and normal install of 5 hours. Avalon Racing (NH) has them on sale for $620 + shipping. IMO - a great deal with improved perfromance & quality.