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The problem is not enough people use them...and there are only two distributors for them in the whole country.



If more people carried them and sold them, think of the actual advances that could be made.


I keep some building secrets to myself, but my squish is WAYYYYY less than .050
 

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I like to run a looser squish but more timing personally....if I tightened up mine to low .040's I'd have to back off the timing, which is easily adjustable.

I hate changing domes...lol.



Bubba...some tracks we go to (went to) you could make 3-5 passes back to back, as fast as you could get in line.

That tighter squish builds a little too much heat for my taste.
 

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I fell That .36 is way to tight I would not suggest anything lower then .42 but what do I know


The only thing I am going to say.......and I dont mean anything bad by this so please dont take it the wrong way.

If you dont know what your MSV is or how it affects combustion (maybe you do), how do you know that .036 is too tight? Squish band width and angle play a part in MSV, so they have to be factored in as well.
 

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Pipe post turned into a dome post.
Thread Jacker Alert!
 

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I figured I'd throw my .02 worth in the pot, when I had my 10mil cub, I tried both small bore and big bore pipes at the track (same track) and the big bores gave me a quicker ET, and seemed to have a broader powerband. We're not talking about a major difference in ET, but the gain was in the 60' time. Both pipes seemed to make the same power, just the small bores were more "peaky" where the big bores had a more solid pull, which is probably why it helped on the low end of the run, giving me more power to pull out the hole. Just my observation.
 

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Discussion Starter · #31 ·
Thanks for the input Travis.



Well, I got some new domes that were supposed to be less compression and ended up giving it 210 psi and 0.052" squish. I think the motor is positive deck, so the 20 cc domes don't actually come out to 20cc bolted on.



It ran 3.99 @80 first pass with me on it (185 lbs.) It ran 80.X mph 90% of passes regardless of 60 ft, or if it bogged or got sideways. Gearing is topped out, I think. One a good pass with a 1.45 60ft, I had to try 3 times to hit 5th, so it only went 75 mph and still ran 4.004. My 60ft and 150ft times were 0.07 seconds faster than any other pass, so I figure that to be a 3.92 pass if it would've shifted.



These were all passes with SB pipes. I am very pleased with this motor so far. Not the fastest 10 mil Cub out there, but it's consistent and fun and will probably get dialed (with better gearing) in the mid to low 3.90s and probably have a few .80s on a good pass.





I will compare back to back passes with BB pipes and keep ya'll posted.
 

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My 10mm cub made 109 hp with bb shearer in frame pipes on gas, Would it be worth the money to try oof pipes? matt shearer told me he thinks i could pick up about 4-5 hp if i switched to small bore oof pipes.
 

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My 10mm cub made 109 hp with bb shearer in frame pipes on gas, Would it be worth the money to try oof pipes? matt shearer told me he thinks i could pick up about 4-5 hp if i switched to small bore oof pipes.


Matt has had that result on quite a few of the 10mill cubs as well as the 4 mill cheetah's. Ask "Mailman".... He'll tell you the same thing. But you will only see those improvments with the "New Style" SB OOF's.
 

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i wish i had a hot chick next to my name..



dome's are a whole nother thread!!..



i like a lil more squish with a short band and a very flat profile from the plug out.. and lots of timing on alky. on smaller motors.. cubs i wouldnt ever go more than .42-.45 they will push the head up and nuke.. i think stockers you can run tighter than that. think i've ran down to 35ish on a few? dont rember oh well time to find some random hot chick to get an avatar for!
 

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i wish i had a hot chick next to my name..



dome's are a whole nother thread!!..



i like a lil more squish with a short band and a very flat profile from the plug out.. and lots of timing on alky. on smaller motors.. cubs i wouldnt ever go more than .42-.45 they will push the head up and nuke.. i think stockers you can run tighter than that. think i've ran down to 35ish on a few? dont rember oh well time to find some random hot chick to get an avatar for!
I run my 10mm 35-38 squish, and my brother runs his 4mm the same. I run a 9mm band with the blaster angle and 19cc domes at sea level. I know it's alot of compression ant set up tight, however can't argue with around 110hp with inframe pipes on c14 gas. I have ran this for 3 years with no problems.
 

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Discussion Starter · #36 ·
Tried the "new" SB Shearer's along with a new, much better chassis. Ran best of 3.85 sec, 1.41 sec 60 ft. Consistent 3.86 to 3.91 e.t.s. all day long (183 lb rider). Don't know if I even want to try another pipe on it. Couldn't be happier with the motor/chassis combo I have now. Even with what seems to be strange specs (loose squish, lots of compression) this motor screams.
 

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Discussion Starter · #37 ·
UPDATE: Ran back to back runs SB vs BB.



SB: [email protected] 80 mph 1.41 60ft.

BB: 3.89 @ 80 mph 1.41 60ft.



Clear as mud. lol. Sorry, don't have those time slips; but I do have these:



Best pass with BB. (Don't mind the reaction time - Damn staggered heads up tree gets me every time, lol)







Best pass with SB. Same track, different day, different tires and different track conditions. Not really apples to apples.









On another note, this motor/chassis combo runs about the same times at 3 very different tracks with only tire pressure adjustments. It even ran identical times (and mph) going from 72 r/o 14 staggereds to 76 r/o 14 staggereds with NO gearing change. Good 60 ft times are easier to obtain with the bigger tire, but not better (I had more 60 ft passes in 1.3s with the big tires, but still had some 1.3s with smaller tires).



To sum this thread up. I would say that the BBs are easier to get down the track being more forgiving. I can shift into 3rd gear quicker with the BBS without fear of falling out of the power. I believe with both pipes that I could have geared a tooth smaller in the back and ran even better if the 60 ft times would stay good. I am certain that the BBs would pull higher gear.
 

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IMO (estimates are made with a 196 ex 130 transfer) BB Drags make pk power at about 9600 BB inframes make pk power at about 9800-1000 SB inframes make peak power at about 10200 SB drags make peak power at about 10000 that being said these pipes are all different. If the results are the same at the track then the set up of the engine is not optimal for any of these pipes. When you are on the dyno and the engine is loaded on a 10mm cub it is clear that a SB drag has the most USABLE POWER (in most cases) the key is to see what pipe has the most usable power in the rpm that the motor is being used. For example if a pipe is 15hp better at 7000 rpm but the same at 10000 rpm and down 15 hp at 11000 rpm in a drag race it will be slower than the pipe that was down 15hp at 7000 but 15hp better at 11000. for a duner it would be great. Back to 10mm cub It is possible to make a 10mm cub (and a 4mm cub) work really good with our BB inframe pipe and drag pipe. These set ups are not an over the counter set up (to me) some builders prefer BB on 10mm cubs (Nate Mcoy for example) But these set ups are built specific for that pipe. Most people build there stuff at home and dont have this kind of set up. We will be working on testing the 10mm 68 bore cub (again) as cast and top ends that were built by KNT and Nate MCoy (they both like different set ups) very soon. This will be done on our dyno and at the hill and 300ft track. We did this a couple years ago on the dyno and on the hill and found the New SB drags to be the fastest on the hill and they also had the most usable power on the dyno. On a personal note we have had alot of 10mm and 4mm cubs on the dyno built by alot of different builders and SB drags are the best everytime Ive never seen a 10mm cub with BB drags out perfome the new SB drag on the dyno or the hill. Not saying it isnt possible. That being said we havnt tested any of Nates cubs and he prefers the BB. Just my 2 cents thanks
 

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Discussion Starter · #39 ·
I think I'll have to take both sets of pipes with me to another track for another back to back pass. As of right now I prefer the (silenced) BBs on them, even though SBs look so much better, and mount easier to my chassis.
 

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I wanted to throw this in as well. I usually run the shearer SB out of frames on my 4mil cub. I had the chance to try a set of big bore CPIs. Now the CPI big bores are done differently than how Matt does his big bores. Think of them more like a small bore pipe with a big stinger. I know it's not exactly that but we'll just say that for easy thinking on it lol.



I was running them on the 1/8th mile asphalt. In the 330ft scenario, the big bores run practically identical to the small bores. The 60ft and 330 mark all showed about the same, and that was taking into account weather, track conditions, and making a lot of passes. We run there alot and I know the track well. Where the small bores started to shine was after the 330 mark. The pull out much better for my motor after the 330, when in 5th gear and sustaining more upper RPM over a longer time. I have a lot of exhaust area and wanted to see how the big bores would perform, but obviously the motor CC size is still limiting me to staying with a small bore pipe. Good info none the less.......

The small bores at the 1/8th mile mark are worth about 3mph for me, and they still perform well down low with a lot of gear, providing clutch setup is right. Hope that might help.
 
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