Anyone know any #s? Fastest NA, Internally stock ITR w/ ITR motor? Just asking b/c after running 13.8 w/ i/h/e I decided that I'll wait till winter to do cams/head work and see how fast I can get it without opening the motor, and staying NA. The car will def. do 13.6 as it on the right night (it was 93 degrees and 60-70% humidity)...I figure w/ open header, tons more weight reduction (but maintain the full dash & speakers), lightweight fly and crank pulley, FAL Rad., and some other little things I could squeeze a 13.3-4 on street tires.

 

Open header is not as good as a really good exhaust.

George Knighton's R makes really awesome power on stock internals... 192 whp ?? HUGE midrange... and apparently he could have had 200whp peak, but that would have sacrificed essential midrange hp/tq.

If you ran a 13.8.... I bet a car like george's would be faster. I don't know anyone who makes 192+ with a graph like his on stock internals.

So, before you get internals, get a SMSP header/full exhaust, hytech header/full exhaust, have someone really good tune a hondata system for you, and go rip it up.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris N &raquo;</TD></TR><TR><TD CLASS="quote">Open header is not as good as a really good exhaust.
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please explain why

 

Jack Harris said this in a post last year about open header:

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">
If you have a "proper" cat back, you will see minimal gains by running open header.
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I have also ran across some dyno plots/information from SMS comparing his header/exhaust with open header, showing very similar power numbers, with little/no difference.

I cannot find the exact thread, but comments like Jack's (and I think jack and dave/smsp would know) that a properly tuned exhaust (i.e., exhaust velocity, diameter, etc) makes just about as much power as possible, given the rest of the engine's modifications/setup.

Maybe someone more knowledgable can chime in and correct my generalizations and assumptions... but i KNOW that running certain exhausts/straight pipes tend to make equal/better power than staying open header. I've read many comments by very intelligent people like Dave S on this... I searched about 25 threads and only found a small amount of what I was looking for.

 

I think in sms's test, he didn't really run open header.. he just added longer pipes.. and then compared that to a full exhaust system.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris N &raquo;</TD></TR><TR><TD CLASS="quote">Open header is not as good as a really good exhaust.
If you ran a 13.8.... I bet a car like george's would be faster. I don't know anyone who makes 192+ with a graph like his on stock internals.
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I don't doubt that at all, I'm by no means saying i'm the fastest. I was wondering what the record is. I'm just wondering how low people have gone. I'd like to try to see if it's possible for low 13s on street tires, internally stock, NA.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JoesTypeS &raquo;</TD></TR><TR><TD CLASS="quote">

I don't doubt that at all, I'm by no means saying i'm the fastest. I was wondering what the record is. I'm just wondering how low people have gone. I'd like to try to see if it's possible for low 13s on street tires, internally stock, NA.</TD></TR></TABLE> doubt youll do it on street tires.

 

I ran 13.28 with street tyres and open header once.The car was w/o pass seat ,s/wheel.It was a night event .I usually run 13.3/4