Spent the morning at Loynings on the chassis dyno with Doug.

Very Interesting - I'm down about 20hp on top, from 7500 to 8500. Doug put it to me like this: "You're Consitpated."

And thanks to my Houseman gears I've been spending lots of time there.

Hmmmmmm - Could it be:

The Loback Muffler? Ummm - probably not.

The 2-1/4 pipe I used from the collector back? Duh - YEAH.

The Comptech standard 4-2-1? Maybe at the tizzop.

The Comptech Icebox (compared to the Mugen box)? Maybe at the TiZop.

It's time to take the Dunce cap off.

I'm gonna hack up the Mugen 4-2-1 to maximize ground clearance and allow me to adjust the secondary length, redo the exhaust in 2-1/2, stick with Loback for the muffling, and put the Mugen Airbox back on.

THEN I'm gonna look real hard at my powerband and my gearing and think it thru a little more intelligently.

Scott, who laughs because his motor show's no sign of softening...Will it run forever?

 

the true silly season is identified by 3 tech threads from Mr. Scott on the same page, and ends with the day a N/A Honda motor gains or looses 20 HP from a 1/4" of B-pipe thickness.

 

i really don't think you are losing 20hp because of 1/4 of an inch.....

in fact i know you aren't!! cuz i've been on the dyno many many many times!!!!

 

maybe he means his HP curve drops by 20 from 7500 RPM to 8500 RPM

either way, post dyno

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">I'm down about 20hp on top
</TD></TR></TABLE>

ok...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">motor show's no sign of softening</TD></TR></TABLE>

Except for the 20hp loss... Riiiiiight...

Christian, who's afraid to see how much power his engine does (or doesn't) make

 

it obviously makes plenty.....

 

Not being silly.

It's down on power from 7500 up.

Sorry - didn't mean to imply it was down 20 the whole way up. The power flattens out and the max differential is 20 at peak revs.

The curve overlays with past runs with the same header are about identical up to that point - except for down between 5000 and 6500 where it's up by about the same amount.

I've got to dig out my old runs and do some comparing.

And it could be that each of these changes contributed a share.

I'll be going back later with a pile of parts to sort it all out. It's just nice to know that it's not all the drivers fault - racing just wouldn't be the same without him.

Scott, who KNOW'S I pulled that rag out of the airbox inlet horn!

 

Silly rabbit.
Just shift at 7500.
Problem solved. Have a beer.

Scott, who says "Gee, its a good thing you bought an expensive gearbox to make sure you stay out of your power band." Good Call
Got any investment advice for me. I gots some cash I'm itching to toss.

 

I'm not a Rabbit...

I'm more of a Coyote....Wiley Coyote unfortunately...

Scott, who's head is giving off a plume of black smoke....

 

From the Warners Bros Website...

Rule 1: Road Runner cannot harm the Coyote except by going "Beep! Beep!"

Rule 2: No outside force can harm the Coyote -- only his own ineptitude or the failure of Acme products.

Rule 3: The Coyote could stop anytime -- IF he was not a fanatic.


Looks like its time for a new avatar there Lord Wiley

Scott, who says Beep! Beep!

 

For myself, as for Wiley Coyote, there is always a next time.

And since I am not actually Wiley Coyote, one of these next times IT IS going to work!

Scott, who is hungry like a Coyote for Speed!...I ain't stoppin!...think of the look on Wiley Coyote's face...."No NOT THAT look! - the one just before that, when he still thinks it's going to work"....That's what it's all about.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Catch 22 &raquo;</TD></TR><TR><TD CLASS="quote">Silly rabbit.
Just shift at 7500.
Problem solved. Have a beer.
</TD></TR></TABLE>

because of the torque multiplication of gearing, you usually operate in an RPM above your peak output.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">Sorry - didn't mean to imply it was down 20 the whole way up. The power flattens out and the max differential is 20 at peak revs.
</TD></TR></TABLE>

again, theres no way exhaust diameter modications in the 1/4" range after the collector are going to gain or loose 20hp, either across the whole band or at one specific point.

are you getting any dark smoke in the exhaust? is the power curve all jagged and spiked at the upper end?

 

Nah.

The car runs good. The power is smooth.

The bottom/mid has more, the top has less. Otherwise the traces are very comparable.

No smoke. Nothing funny. A/F good.

I could hear the flattening during the runs.

Scott, who will find the reason...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">Scott, who will find the reason...</TD></TR></TABLE>
Beep-beep!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">Nah.
I could hear the flattening during the runs.
</TD></TR></TABLE>

whats your compression, and how much of that was obtained from milling the head?

and this may sound off-teh-wall, but what piston & rods do you have? all stock B18C5?

Huge cams?

 

Bone stock 98 ITR.

Never had the head off.

External bolt on's only - Header, Airbox, Mugen ECU, FPR, race exhaust - that's it.

Peak was 174 whp at 7500 on the Superflow.

I'll post up the relevant sheets in a day or two.

Scott, who would really hate to find the Loback having much of a role in this...that'd leave only the expensive Burns Stainless 3.5 inch OD muffler to try...

 

I say more on top is better. I compared shifting into 5 th at Watkins Glen at 8400 on the main straight to staying in 4 th until 8800 (my new Hondata redline) and it was much, much faster to stay in 4 th and use the good top end on my motor (182 whp max) as per my data logger. The speed trace just went flat for the shift into 5 th compared to the rise while staying in 4 th. You need the juice above 7500 if you wanna be fast again. It takes so long for the revs to rise above 7500 RPM while in 4 th gear, you have time to do your nails, or as Eddie Irvine once said, "eat your sandwich". You can't afford to lose it there.

Why did you change the stuff on your motor? Short of cash for the new Motons?

Sounds like you are going to have to spend some more money. Will it ever end;-)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by descartesfool &raquo;</TD></TR><TR><TD CLASS="quote">... if you wanna be fast again. </TD></TR></TABLE>

&lt;Sally Field accepting the Oscar On&gt; I WANNA BE FAST AGAIN!

I took of the Mugen 4-2-1 to save it from anticipated destruction at the ridiculous ride height I've been running.

I took off the Mugen airbox to save it from anticipated destruction in the fierce competition I anticipated. (Just kidding - but that is the side I bent in my first race this year - and it probably would have cracked the Mugen inlet horn).

Yeah, I was going to sell them to speed the recovery from the Moton's...but then I didn't.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by descartesfool &raquo;</TD></TR><TR><TD CLASS="quote">I Sounds like you are going to have to spend some more money. Will it ever end;-)</TD></TR></TABLE>

"Oh Yeah, Definitely, once I get these last few things done I'll pretty much leave the car alone and just drive it."

Scott, who knows deep down that it will probably never end...

 

Get a "good" header Scott ... you should know better .... Ed

 

So that's why you weren't racing at PIR last weekend, you were busy getting ready for the dyno?

 

is the comptech for sale?