GSXR draw thru - jet sizes??

[blastard]

Hi,

I own a gsxr1100m/B12 draw-thru turbo.

I've just had a b12 barrel rebored to 81mm to take my gen 1 busa pistons (with brand-new rings). The setup is draw thru with a mikuni HSR42. Now I've been running this turbo beast for the last 5 years with various piston configurations (standard 1127cc, 1154cc (bandit pistons), 1186cc (MTC turbo pistons = destroyed) - but want to go back to the busa piston setup.

For the life of me I cannot remember the hsr carb jet/needle sizes I used to use with busa piston setup. Something just to get it in a ballpark area so I can give the bike a brief test ride (to check for any probs) before it goes off to the dyno for final setup.

Is anyone running a similar setup? and could give me their baseline jetting. I currently have;

pilot 25 (std)

needle 97 (std) on middle clip position (std)

main 240

pilot screw 2-turns out (std)

 

Any info appreciated. Its been over a month since I rode it (but I'm lucky i have a 240bhp supercharged R1 as a back up ride lol)

 

Kev B

Edited August 22, 2016 by blastard

[Duckndive]

My Motor is similar spec 1216 using busa pistons  T3 Turbo but I use an S & S Super E "ditch pump carb".....using a 270 ish main

Thread Here http://oldskoolsuzuki.info/forums/index.php?/topic/22-when-na-is-not-enough/&page=1

I did run a air cooled 1188cc motor with a T3 and HSR 42 from memory I ended up with a 250 Main .....

Yours don't sound to far out on paper ...  I,d go up to a 250 and run it down the road and do a plug chop

 

[blastard]

Thanks for the reply, Duckndive.

the main jet is not my main concern as that can be finalised on the dyno (i.e. goin fast!). My biggest issue is from tickover upwards. The current 'standard' setup (as listed in my OP) doesn't have the motor reving nicely hence my post. Because I live right next to what appears to be the entire elderly population of my home town, Its not really possible to keep swapping/adjusting then running the motor up to temp to test. I'm after an approx baseline for pilot jet and needle size/position so it runs 'reasonably' well so I can get out of town for any fine fettling/plug chop - before dyno visit (60 miles away). Btw, my blower is a T3/T4 hybrid (not that really matters here).

Thanks again for the info. I'm kinda hoping someone on this forum has that same carb as me on the same gsxr/busa/garrett on a draw-thru setup.

Kev

[Duckndive]

3 hours ago, blastard said:

Thanks for the reply, Duckndive.

the main jet is not my main concern as that can be finalised on the dyno (i.e. goin fast!). My biggest issue is from tickover upwards. The current 'standard' setup (as listed in my OP) doesn't have the motor reving nicely hence my post. Because I live right next to what appears to be the entire elderly population of my home town, Its not really possible to keep swapping/adjusting then running the motor up to temp to test. I'm after an approx baseline for pilot jet and needle size/position so it runs 'reasonably' well so I can get out of town for any fine fettling/plug chop - before dyno visit (60 miles away). Btw, my blower is a T3/T4 hybrid (not that really matters here).

Thanks again for the info. I'm kinda hoping someone on this forum has that same carb as me on the same gsxr/busa/garrett on a draw-thru setup.

Kev

from that it Sound's like you need to adjust the point that the accelerator pump starts to hit....

For what its worth I dint touch the pilot jet or needle on mine ....

[Reinhoud]

There's only one way, a O2 sensor with gauge.  

[blastard]

Yes agreed. I have a wideband AEM air/fuel ratio gauge and Bosch sensor installed. I changed the pilot to 35 and needle to 95. Starts and revs quite nice now. Went for a brief run, didn't get out of 3rd but noticed afr was 15 ish (although not really under load). Will pop out again tomorrow and check again but reckon it needs riching up a bit from 1/8 throttle onwards. Will lift needle 1 click.

When should acc pump on carb come in?

 

[Reinhoud]

On 8/24/2016 at 4:56 AM, blastard said:

Yes agreed. I have a wideband AEM air/fuel ratio gauge and Bosch sensor installed. I changed the pilot to 35 and needle to 95. Starts and revs quite nice now. Went for a brief run, didn't get out of 3rd but noticed afr was 15 ish (although not really under load). Will pop out again tomorrow and check again but reckon it needs riching up a bit from 1/8 throttle onwards. Will lift needle 1 click.

When should acc pump on carb come in?

Whenever you like, but I think it's better not straight away.