Q98 pipe
- Thread starter zipracing
- Start date
Yeti Racing
New member
Damn Al think about what u r asking. What happens when u over carbe on a short tight track coming out of corners or over carbe on short straights vs. a long sweaping track with larger carbe where the engine can stretch out & Eat or under carbed on longer sweeping track where it needs more but doesn't have enough. THINK man THINK
MikeGrady
Member
That's OK. Just telling you what Hilton's engine did on Kermit ' dyno. Maybe I'm wrong. Ask Hilton.
Mike
Yeti Racing
New member
IMHO - KB 06/Q98/KB01/KB02/KBDOM/original noise banned KBDY?? or RLV Pro80 or 81/82 or S3/S4/G2 & original RLV noise banned pipe w/o label (just weld a good muffler section on them - but more to come on that forthcoming later) on alky or gas I get approx 10% more hp by switching alky vs gas carbe regardless of the pipe on the same engine nothwithstanding flex & other such adjustments. The factor surely seems to be the fuel & not the pipe. I've heard all the arguments on sound waves in the pipe depending on the fuel type & alky pipes vs gas. IMHO a good pipe is a good pipe for the situation regardless of fuel type. Not withstanding the out of the corner alky bog. I just happen to favor all those pipes I mentioned above JMHO
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That info is something I've always wanted to know. If there is any difference with pipe designs for alky or gas it seems the differences are fairly small. Definitely not enough difference for me to be worried about when running our mandatory gas fuel. I mean I assume we are talking same compression and head designs and measuring the difference in engine performance with just a change over from gas to alky carbs perhaps with a small ignition adjustment.
Yeti Racing
New member
IMHO - that sounds like a great setup for a stock ported 115 albeit with one mod I'd drop the 34mm down to a billet cup atomized 29mm alky. if it were a real upper middle to full tilt open ported 115 with 11.5 cc combustion chambers (some pretty good compression with that size piston) I'd bump up to a KB01 or RLV Pro 80 (maybe modified with a 2nd exit hole depending) & go with a billet cup atomized 34mm and a very high slip to get it on the pipe out of the corners with that carbe. - JMHO
Yeti Racing
New member
Arc - FYI - Just remember one significant difference in alky vs gas is with alky ur probably going to run .010 Before TDC more timing advance than u will with petrol (gas) for example -- .090 BTDC on petrol & .100 BTDC on alky. If u plan far enough in advance u could run a 12.5cc combustion chamber volume (lower compression) and perhaps another .005 (maybe go from .005 ---> .0055 clearance) & bump the timing on alky to .110 BTDC if u need to set the engine on "KILL" to beat the top 5 in the country. This is notwithstanding there's nothing left to get out of your kart & physical self and your handling , tires, grip, chassis setup, brakes, are dead nuts ON. It may come down to plenty of water & juiced veggies & not eating solid food & a triple dose of metamusal 48 hours before race time. Hey whatever it takes to be a champion. Oh my.....LOL
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Arc - FYI - Just remember one significant difference in alky vs gas is with alky ur probably going to run .010 Before TDC more timing advance than u will with petrol (gas) for example -- .090 BTDC on petrol & .100 BTDC on alky. If u plan far enough in advance u could run a 12.5cc combustion chamber volume (lower compression) and perhaps another .005 (maybe go from .005 ---> .0055 clearance) & bump the timing on alky to .110 BTDC if u need to set the engine on "KILL" to beat the top 5 in the country. This is notwithstanding there's nothing left to get out of your kart & physical self and your handling , tires, grip, chassis setup, brakes, are dead nuts ON. It may come down to plenty of water & juiced veggies & not eating solid food & a triple dose of metamusal 48 hours before race time. Hey whatever it takes to be a champion. Oh my.....LOL
Why do you say petrol? thats what its called here, petrol for petroleum fuel. You guys normally say gas for gasoline?
alvin l nunley
Site Supporter
I have no experience with what you guys are running now, but with my Macs, on alky, I set the timing with as little advance as possible. Nobody had a faster 125 then me.
Even with my stock foreign K 78, which finished 2nd at the 1977 nationals, and 1st in the last heat, I had the timing set at .060" BTDC.
"Blubbering on the low-end" I don't understand that. Seems like a simple carb adjustment to me. What am I missing?
I really don't understand lower compression ratios! There is a limit, with gas, because of detonation, but that limit is much higher with alcohol. Compression is, "the Holy Grail." And nobody can convince me otherwise.
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory.
Even with my stock foreign K 78, which finished 2nd at the 1977 nationals, and 1st in the last heat, I had the timing set at .060" BTDC.
"Blubbering on the low-end" I don't understand that. Seems like a simple carb adjustment to me. What am I missing?
I really don't understand lower compression ratios! There is a limit, with gas, because of detonation, but that limit is much higher with alcohol. Compression is, "the Holy Grail." And nobody can convince me otherwise.
Comments compliments criticisms and questions always welcome.
If the data does not support the theory, get a new theory.
I agree 100%. Your knowledge is far greater than mine. I don't even have a clue what ur talking about when you say atomized carb, cup atomized. Forgive me just my lack of knowledge. We just use what we have on hand. Try to call carb guys and they just give cold shoulder unless ya shell out some big bucks. I currently run a h2o PCR 100cc, mildly opened, kb06 with 34mm alky mikuni. Any suggestions on a possible better pipe/carb combo?
Yeti Racing
New member
Nunley - " I really don't understand "
Nunley - " And nobody can convince me otherwise. "
Well... Al ....
BANG !! U hit it right out of the park. ;p
IMHO -
What can I say u said it best urself.... And who am I to argue otherwise ? - JMHO ;p
Damn this forum is pure classic
Nunley - " And nobody can convince me otherwise. "
Well... Al ....
BANG !! U hit it right out of the park. ;p
IMHO -
What can I say u said it best urself.... And who am I to argue otherwise ? - JMHO ;p
Damn this forum is pure classic
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Yeti Racing
New member
error hi-jack sorry will re-post OC
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alvin l nunley
Site Supporter
I can only guess of course, but it sounds like you can't answer the questions. I can only go by what I hear, but I hear there are over 5,000,000 comedians who have stopped looking for work.
MikeGrady
Member
That is interesting. I was never really happy with the KB01's power band width or its over wind capabilities. I was always happier with a Pro 81/2 or a KB06. I always needed dual carbs on them due to cooling issues on the air cooled engines. Now, if you ran it at a track where you breathe the engine a whole bunch a single is fine but if you can really stay on the fuel to the point where you are lifting for just a second or two, I just never had luck with a single carb.
There are some tracks where even the KB06 pipe doesn't have the band width I need. A perfect example of that is Daytona. That place requires that you really slow down in the corners and I like to stay off the clutch in the corners so that requires more band width. I am hoping the KBL, with the proper cylinder mods, will give what I want.
It is interesting to see things from a different view......
Mike