air box result modification

[OB_Erik Gendron]

Hey,
I would like to know if someone did some dyno test with a Yosh tri-oval and BMC air filter with the air box modification...
I just bought the tri-oval and the filter and I am waiting to modifed the air box if it`s OK...

 

[OB_c.dolan]

Same day /all stock: 156 hp. //mild airbox mod, stock filter, yosh pipe: 164 hp. on Dynajet dyno, Lee Cycle (in San Diego, Ca.) They have had higher readings, on other Busa's, with Akro pipe, but said mine was the biggest before and after difference.

 

[OB_S@UER 1300RX]

How does the yosh sound?

 

[OB_c.dolan]

Sounds ok, not too loud. Didn't get a chance to hear the Akro pipe.

 

[OB_Erik Gendron]

Sound great...in my garage the wheather is
-16 degre in canada.

never heard akro pipe before.

erik

 

[OB_Xen Racer]

I have the Tri-Oval and the BMC installed. Sounds good, nice HP increase.

I was waiting to do the airbox mod, since I heard that it hurts the bottom end a little.

Does anyone know if you can tune this out?

 

[OB_c.dolan]

Have done air box mod, and haven't
noticed any loss of bottom end. PC II box
is easy to adjust, and you can fatten up low
end 1, or 2 notches, for better throttle
rsponse. This basic adjustment can be
done without a lap top computer.

[This message has been edited by c.dolan (edited 06 January 2000).]

 

[OB_Xen Racer]

C. Dolan,

Thanks for the info. I have been looking for an excuse to buy the PC-II.

Have you dyno'ed the bike since doing the airbox mod? HP increase?



[This message has been edited by Xen Racer (edited 06 January 2000).]

 

[OB_Jaffie1]

I recently installed a Micron pipe, BMC (RACE filter) and the KN commander on my Busa and I was very pleased with the results. I started with 153rwhp and ended with 166.8rwhp that is a gain of almost 14hp on a DynoJet Dyno.and we left the air box alone.

 

[OB_c.dolan]

To Xen Racer: Dyno run mentioned earlier. Stock: 156 hp. / Mod.: Yosh pipe, mild airbox cut out ( still using stock air cleaner) PC II , made 164 hp, same day. I didn't the highest hp. , compared to others they have done, but I got the biggest difference in the before and after. Since PC II is easily adjusted, I have made some minor changes at the strip. ................................. ... Dyno can get you in the ball park, but have noticed outside world different. I made busa 2 notches leaner for top end , in quarter mile. Have a 99 Harley that takes 2 jet sizes richer main jet, in quarter mile, than best jet, on dyno. It dropped .2 sec on et. , and picked up 2 mph.................................... ..I use the Harley as an example, since I haven't been able all the hp to the ground on the Busa. Running wheelie bar this weekend, or next. Still trying to get a "9" out of it, but I weigh 220.

 

[OB_c.dolan]

Mild airbox cut would be inside contact area of filter, on bottom. Hot knife would be a lot cleaner, than rotary file, as far as chips are concerned. You'll need to cap off small hose, on vacume door that's being eliminated. Also, plug big hole, toward back, with something about the size of a quarter. I glued a plastic film can top.................................... ..Your rider weight will determine the best rear sprocket to use in quarter mile. I weigh 220, and use a 42 t. rear, to get most of 4th gear at finish line. Depending on your weight, you'll probably want to short shift (@ 10,000 rpm) from 4th to 5th, to get a good mph at finish line.

[This message has been edited by c.dolan (edited 07 January 2000).]

 

[Frank Adams]

c.dolin: That short shift from 4th to 5th waste time!

Better off trying to get that bike to go through traps at 10,000 rpm's in 4th.

That short shift will kill your ET.

 

[OB_c.dolan]

To Frank Adams: 10.000 would be a good
number to cross finish line. However,
with the gearing (43 T ) the other guy
described, he may be at 10,000 well
before finish line. I believe there is
only a 1000 rpm drop between 4 and 5, and
maybe as little as 750, between 5 and 6.
I have drag raced bikes since 1970's, and have sometimes shifted at different rpm, depending on gear. I'm going to the track tomorrow, hopefully, to try some low gears, and wheelie bar. (stock motor.) Will experiment with gear / rpm drop / shifting combos. To try to get best average hp use, according to a recent dyno chart, I will shift as follows: 1 ~ 2 : 10.5 ~ 11k / 2 ~ 3 : 10.5k / 3 ~ 4 : 10 ~ 10.5k / 4 ~ 5 : 10k / 5 ~ 6 : 9.5 ~ 10k depending on distance to finish line. Will run 16 t front sprocket and 46 t in rear. Will make adjustments in shifting, and gearing, depending on results. Peak hp on my bike occurred @ 9750 rpm on dyno.

 

[OB_Xen Racer]

C. Dolan,

I forgot to mention, I just got my bike back from the shop today after adding the Sprocket Specialists ultra-lite 43 tooth rear sprocket. In the case of the Hayabusa it is no coincidence that sprocket rhymes with rocket. This thing flies.

I still have not done the aitbox mod and added the PC-II. But plan to do it this week.

Any tips?