Brocks SMEG... ZERO gains?

[Goatkart]

ODD, i know...


Had my brocks SMEG put on yesterday....

I didn't get to make a same day pull on the dyno for the bike with the slip ons, just a tuned and untuned smeg vs an older dyno i have from in march...


Long story short....

After swapping on the brocks SMEG with NO tune, i LOST about 7rwhp and 6tq from my march baseline...

it was running fat as all hell(which ALSO confused me, free flowing exhaust should lean an engine out, not fatten it up) on the dyno....


After the tune, i was at basically the same HP AND TQ as i was with my previous tune with slip ons, AND dropped a little torque on the low side below 3000 rpm...


AFR looks fine, if not a smiggin lean at 13.2, excluding a spike where she goes fat around 3500-4500 rpm

Im thinking this might be my bog on the low end i've been feeling...


I am a BIT lost on this one.... i wish i had a slip on dyno done the same day but i dont...


The weather conditions were significantly different, however, im not sure if the busa does timing retard based on IAT's or anything similar to account for a zero gain....

correction on first dyno was 1.01 STD, correction on most recent dyno was 1.06 STD



Dyno(3/22/10) previously was 150.0 rwhp, 89rwtq STD 1.01 correction
61 degrees
29.3 hg
16% humidity

Pre(6/22/10) Tune Dyno 143rwhp, 86 rwtq STD 1.06
97 degrees
29.49 hg
45% humidity


final(6/22/10) dyno after retune 148rwhp 87rwtq STD 1.06 correction
97 degrees
29.49hg
49% humidity


so a gain of 5/1 tune vs untuned, but nothing compared to my slip on dyno....


input?

 

[Goatkart]

side note..

butt dyno says the bike is faster... revs faster.....

but im not sure how much of that is less weight vs sound placebo effect vs gain that im not seeing...

Oil was changed to amsoil not long ago, chain lubed, tire at 38lbs vs 40 back in march (i had checked it that day i remember)

chain was "tight" with in spec for sure, as it was rechecked and set when the bike was lowered...


None of this has changed from before to currently.... BMC standard air fliter, +3 rear sproket, small box mod

 

[m_ridgeway]

have you changed rear tires?

 

[Goatkart]

same tire first dyno to current...

Ultra soft's ~1000 - 1500 miles since then... still plenty of tread, and i didnt notice any excessive tire spin(tire got a nice glaze on it like it had done a burn out, and was nice and tacky at the end, this happened on my first dyno as well)...

 

[Goatkart]

Here is my Dyno sheet...

Before Tune BLUE
After Tune RED

 

[Goatkart]

RED line "base line" i used... this was a retune after a bad tune...

Blue Line Bad tune i had at one point.... pretty obvious to see the difference between the two...

 

[m_ridgeway]

same tire first dyno to current...

Ultra soft's ~1000 - 1500 miles since then... still plenty of tread, and i didnt notice any excessive tire spin(tire got a nice glaze on it like it had done a burn out, and was nice and tacky at the end, this happened on my first dyno as well)...

you can see a loss from the soft tires. since it was on the first one as well i dunno. maybe the temp of the tire was a little higher since the dyno temps have changed quite a bit?

somethings for sure up. you went from a slip on to a brock s-meg full system right?

 

[Goatkart]

you went from a slip on to a brock s-meg full system right?

Correct, i was so baffled i even double checked, all brand new header up front...

old exhaust Yoshi TRS slip ons stock oem header...

 

[Johnnycheese]

what gear was they done in? also those soft tires can cost anywhere from 4-10 ponies they get greased real bad after 4 or 5 pulls and then you add mapping and load and go away fast.
someone has way too much fuel in at 4k

 

[Goatkart]

Thanks for the input Johnny...

The pulls on the recent pulls for the exhaust tune and pre tune baseline were done in 4th..

There was some supposition that maybe the original pulls were done in 5th, however, when we did a 5th gear pull to see, the difference was maybe 1hp and 1 ft-lb

I plan on getting ahold of them about the 4k thing, its causing the bike to actually bog a bit up to 4k (no big surprise there)

 

[Johnnycheese]

have them give you a copy of baseline slip ons and full all on the same graph that will show something

 

[Goatkart]

have them give you a copy of baseline slip ons and full all on the same graph that will show something

Will do...

I'm going to be calling them tomorow about trying to get back on the dyno and address the fat dip around 4k... When i get back on the dyno, ill have em print out those two pulls together..