Chris,

Could you please explain what you me when the engine " runs on " at the end of the straight??

I currently just picked up this motor and I broke it in (heat cycles) yesterday and took her to the track today to get a good tune for racing tomorrow. I feel like I'm pretty close to a great tune on the engine but any advice is always welcome. Thanks for posting your method.

It's actually Brandon Melton's method. He is a AE/Reedy/Jconcepts factory driver.

I'm not sure. I do know that some people have a rich bottom end and a lean top to compensate. When this happens you need a higher idle. You can end up with to much fuel entering engine and the engine will need to burn that fuel before coming down to idle. This causes what I call run-on. The engine doesn't come off of high idle to low idle right away. That is why a proper idle gap and tuning the bottom is so important.

I'm sure someone else can explain it better or different.

You want the engine to come off high idle and to go to a low idle really quickly. Other wise the car will feel like it's pushing.

I've never experienced this. I have had good engine tuners with me all along. I've learned from them. I'm still developing my ear to the engine. Feeling what the engine is asking for. It does talk to you. It comes with experience.

I have a brand new HPI .25 for 80$ if you need it lmk

Dude that is very well put.

Thanks, I appreciate it. Hope it helps someone.

i'm on my 8th tank preheated before each tank. taking my time winters here.

If properly broken in, I have not heard of any rod failures. I've never replaced a rod before replacing a p/s and haven't had any premature failure.

No. I don't have any cranks with the red, and I haven't had any issues. Obviously they do exist, but there are plenty of cranks with black silicone that are just fine, unfortunatly there is just no way of knowing unless it happens. If it hasn't happened after a gallon of fuel, it more than likely is good through the rest of the life of the engine.

Ok,cheers for that,i will just wait and see,hopefully all will be fine.

YA hopefully ,i took of my carb out(after reading about this) and used a pick to see if the black silicone was secured and it was hanging on by a thread im sure the next time(s) i were to race it would have came loose ,so i shipped it AE to repair ,we will see ?

lots of help at the lhs there, its running hot because its too new. the motor needs to be "broken in" before you worry about temps. it was not running without the ignitor before cause the idle was too low or the lsn too rich. so you went to the lhs and they leaned it out a bit but its still not broken in. if something happens to it now don't came back here posting how bad the motor was and how now its a "shelf queen". some lhs are total crap good luck.

+1

The motor really does take a full gallon to break in. Currently, i get great power out of my motors. My fuel mileage depends on the size of the track and jumps. I have gone 10 minutes with both my buggy and truggy, and i average a temp around 250.

Thanks. Its already a shelf queen. Built to look at. And occasionally race.

as for temps. Ive never had another one of my motors run warm during break in.
Dunno. Im not new to nitro. But im no pro either. Still learning everyday.

Thanks for your insight on my lhs.......

At least it runs. And runs well.

Hey guys, I'm curious. When you have your low end set, roughly how many turns from flush or from bottomed out are you?? I currently feel the motor is broken in and it's making good power where and when I need it. I would like to however get more from the bottom end but I don't want to go too far and have the thing burn up on me. Currently I think I'm only three maybe four hours from flush. And she ran in the 270's at race pace. I'm still very new to the engine but it still scares me when I see temps that high.

2.5 out on top and bottom gets me really close. The bottom end is really easy to box tune. Just fatten it up and listen for the high idle to drop. Keep leaning it until she hardly drops. Also keep your idle gap half of a 1.5mm wrench.