Why did they change the front bearing? The 17011 is the best steel front bearing in the business and I bet they ran out but needed to get motors shipped out. I would be very dissapointed to pay $300 for a engine that don't have the good bearings in it. Anyway thanks for the info and I will get a cooler and give it a try. It will make it easier for my to make one stop in 20 min. mains. Thanks!

Hello, at what temperature they can be used to Bonito and 4BTT? between 250-270 is good or too high??

Thanks. Best Regards.

At least with the ultra low heads

250-270 perfect

My Btt hasn't dropped its nuts yet (still hard to turn over when up to temp with gloves on and the plug in) and I am running around 230 to 240. Monty I think my Btt's nuts are so far north that they are at the RB factory.

Its got a gallon of break in and just over a half gallon of racing on it, including 2 15 minutes mains back to back with a 10 minute down time between with the heater on to keep it up to temp. Its got to be close as I have had to tweek the needles a little at a time the last few runs, but not 100% dropped yet. I can't imagine what she will do when fully broken in running around 250*. I think she'll be close to a 13 minute pit too.

Need some advise. I have a few month old Bonito, and never did anything with the shims and runs great.
Now I have a BTT for my Buggy (rear ceramic), just now getting to about a gallon. I run on the East Coast not very high Altituides, temps vary from 60F -80F running a C6TGC plug with Byron's Gen2 ProDriver 30%/9%. Do I need to do anything with the shims on this engine to get the most out of it?
Any advise is very much appreciated!!

I have been running the new carb for almost a month now. Runtime seems to be the main advantage to using the new carb.

And how much of an average increase in RT did you see?

Based on running the same clutch/pipe/fuel/engine/chassis/etc.

I wasn't able to test back to back at the same track/conditions, sorry.

I figured that.

But did you at least put it on the same (or same model) engine? Like a +4 family.

What was your average increase in R.T.

What do you mean by "Ultra Low Heads"?

It's the new style heads that are on the 4BTT, Bonito, and some other Nova's,

The head sits lower overall than the previous gen of the same engine.

Oh, OK thanks. Was not sure what he meant, as I am new this year. But I guess both of mine are that head cause they are the new Bonito and BTT

Anyone ? Need advice pls... Thanks all.

What restrictor are guys running on the P5XLT? I have the stock 6.5's in both buggy and truck, thinking of increasing to 7 buggy 7.5 truggy whats eveyones thoughts?

Don't know about an XLT in a buggy.

In a Truggy I am currently running a 7mm restrictor just about everywhere. Seems to be just about right. I have used a 8mm for all out power or up at elevation (I live about at about 5000 feet) to help make up for the thinner air. I don't think I'd go smaller than 7mm in a truggy on a XLT. Maybe my thought is off though.