I'm at AC now. Probably could come grab you on first rapid air and have you back in ottawa by about 10 pm

Starting to collect stuff. I'm guessing a new gasket is in order also?

Tim

 

the BB kit comes with the head and base gasket. That should be all you need unless you want a new crush washer for the exhaust.

For what it's worth I have a Harbor Freight torque wrench and we checked it against a calibrated Craftsman wrench and it was dead on.

Also be careful of the difference between inch and foot lbs!

 

I understand the thinking. I submit that your straw will return diminishing results, at some point, as you increase the pressure differential..

Regardless, the idea that a 351 can be properly fueled because it draws more fuel from a 250 carb setup is armchair hydrodynamics/shade tree tuning..

I have found fantastic "new" power curves when the fueling is set to the correct AFR's .
The money and time invested in a 351/TM/Exhaust combo is significant and max power levels (return on the investment) are being left up to untested, unverified carb setups with everyone saying " It runs great"... Not an optimal situation..

 

Sure but when does that happen? I trust Motocross action pretty well. They probably know what they're doing. The bigger bore/smaller jet idea has long history.

Well, yes and no. Armchair not really, because I have done this. I've setup a BB twice, three times actually, and run it on the same carb. They all run well. Pulling an airbox lid, in my experience, changes jetting a lot more than installing a big bore. Also, I have some pretty good people to work with including an ex Honda shop employee. Shade tree mechanics have done some great work. I am old enough now that I am starting to get a gut, so hopefully, I too have learned something about setup in these past 48 years. Experience still counts.

For what it's worth I think air speed in Bernoulli's principle relative to lift is squared. So, small changes in air speed at the venturi will result in a lot more vacuum.Thus, jetting down.

OK.

I am not a scientist and dyno runs are not free for me. The investment in terms of time and money would continue to ramp up as I payed for runs and rejetted the carb and I would have to get ever larger returns to justify the expense. By now, for me, the returns are pretty marginal in whatever theoretical HP gains are left.

The point I am at now is all the power I want. The bike is going to break traction or wheelie. I simply cannot put down more power in my situation. So, while I am very probably leaving something on the table, I can't use it anyhow. New England is full of rocks and roots and hills. It's not about HP so much is about usable.

My friend who ice races his KLX is looking for more top end power and more power overall but I am not. All of my throttle position would be covered by the curve of a dyno run. I ride under my available torque curve at all times.

The horsepower and torque race at some point become theoretical to me. The available torque at RPM exceed my ability to use them I cease to care. In some ways the stock KLX was easier to ride, because whiskey throttle had less consequence and everything was so manageable. The worse kinds of crashes for me is when the bike runs away and I go along for the ride.

My ROI (return on investment) in the engine now don't matter. So, I turned to suspension. Now, I think, pro revalved at both ends I am done with that. If I could have another 10 HP for $20 I wouldn't take it.


The bike will do exactly what I want. Probably next up is Tubliss tires.

I watched with great interest your tuning thread with MCM and DJ. Great stuff.

 

Anyone know the bore diameter of the 351?

Tks

 

It's about that big.

 

Lol, thanks...

Just need to know the actually diameter for the ring compressor size

 

shoot Bill a message, he'll be able to tell you right quick I bet.

 

Done, thanks!

Was just wondering is someone knew offhand...

 

I think we used a wide zip tie and a piece of cardboard or maybe a cut down milk jug. that adjusts to any size.