Trim the hole out a little larger around the cooling head. I think that you'll find fin breakage will be at a minimum,IF any broken fins at all. I used to have the same problem in my Revo. I went through 3 cooling heads in 4-5 races one time. I enlarged the cooling head hole,and no broken fins since.

yes its true we've had at least 8 motors have fins come loose on them they don't break just come loose and rattle around.

I live in New Zealand and our tracks are nothing like what you guys run on what we call a smooth track you would probably call rough to blown out as all track preperation is basically volunter based.

my name is Adrian lorenzen and am suported (not sponsored) by the New Zealand Losi Importer as it is an amature sport over here

sorry Rocket42 I think you may have miss understood me I'm not complaining I love these motors and recomend them to everyone I was just saying that myself and a few others have had fins come loose on the head

anyway thats enough off topic back to GO TECH. I love these motors the seven port I've got just won't die it has huge horse power and gets really good run time

cheers Adrian

also try wrapping the head in aluminium foil to help keep the heat in and away from the carb

Yes our site is in Australian Dollars

We can get up to 11 min 20 sec on a stock 5 port in a buggy and we have gotten 13min 15 sec out of a truggy . You can get these times , you just have to know how. Mind you these tank times arent aimed at engine longevity. At these times you would expect your engine to last 20 to 22 litres tops.

We tune most of our teams engines to about 9 mins on buggy and 12 mins on truggy depending on the surface. High grip surfaces will use more fuel. With this tuning we are getting 35 litres + thats about 9 gallons . All this will depend on the quality of your fuel. it has to have a good oil in it to reduce wear.

Hope this helps

MM

I simply will never believe this claim and feel it's total BS that is bad for the reputation of these fine motors.

I believe 9 mins. indoor on high traction, perfectly smooth, ultra low rolling resistance clay with an ambient air temp of 40 degrees f.

i agree with satoch, 10 min run times are way out there. if someone drives really slow with a leaned out motor, and a really small restrictor, maybe 10 min runtimes. this past weekend on the track i ran on was super dry with NO traction, 10 mins would have been a miracle

MassiveMods is right.

I run my car at Whyalla a few weeks ago and in the 20 minute main, i stopped once at 9:30 still with fuel in the tank and completed the 20 minute main with one top up with a standard venturi restrictor. It was a bit lean but it went the whole distance on a 125 cc tank in a Hyper 8 Pro. So thats 10:30 + on the second top up and completed the race at full noise.

Standard Hyper 8 Pro exhuast and manifold, 14 Tooth clutch bell and a high traction track. Oh and this was a night Meeting and i had to richen it up a little to compensate, so yeah believe it or not i dont care cause i know for a fact, learn to tune i say

Dont say he doesnt know what hes on about cause you will just look stupid, no offense.

Engine is a 5 Port, Stock i might add Using Massive Mods Fuel.

I guess the normal laws of physics don't apply "down under".

i got about 6 mins on my tank of fuel n my 8ight buggy with the restrictor in the tank. it polly could of made 6.5 mins.. and this is at temps of 220 to 230.. i ran my best this past weekend with the go 7port it has good smooth power. ill prolly buy a new one later i just really think the jp3 pipes isnt a good combo with this motor at all.. think id prolly try something new like a 053 or the os2060 pipe..

Mate ide try a OS 2050 thats what im gonna try next myself.
Well on a 5 Port i heard they are great, not sure about a 7 Port.

satoch here is a Lap of the track with my car so you can see how it went and the track condition and no i aint telling lies

7.7 meg http://www.users.on.net/~danzig/Whyalla5Port.avi

Enjoy my stack Traction rolls Rock :]

Well I don't live "down under" so I guess the laws of physics do apply, I get 12 minutes out of my 5 port all day long. It's got a turbo head with a 86 pipe, nothing special. When I ran the 2 hour endurance race at the nitro pit the motor was running at 240-250 for the whole 2 hours and I was pitting every 9 minutes(and that track is huge). I think it's all in the way you break the motor in but that's just my opinion. If you not getting at least 8 min out of a 5 port in a buggy your doing something wrong. Again this is just a opinion of some guy racing toy cars.

The biggest law of physics in question here has to be the acceleration rate of one's trigger finger.

Seriosuly though... what break in method did you use or do you suggest for another "guy racing toy cars" thats interested in getting these long runtimes. I have a 5 port that should be here this week. Can't wait.

JKA, you had to ask didnt you
Oh well here goes.
Disclaimer, i am not responsible if you are stupid and screw it up !!!
--------------------------------------------------------------

Set your EPA to say 15% - 25% on throttle.
Set Throttle trim just above idle, say 8000 RPM
Put Medium/Hot glow plug in the motor, pretty sure i used a LRP 6.
Put good Fuel in the Tank, fill it right up, i used Massive Mods Race fuel for Breaking in.
Grab the heat gun, put motor on Bottom Dead Centre and heat the head to 200 degrees. Make sure you get it toasty but not burn your electrics or car.
Use starter box, do not prime engine with fuel just stick finger on exhaust to prime while its cranking on starter box.
Run engine with trim up on throttle, adjust the LSN so that it runs lean enough to achieve say 220 degrees at around 8000 - 13000 RPM. Engine will be very tight if its stalling at low RPM use heat gun while its running till it will run on its own. MAKE SURE YOU CHECK TEMPS OFTEN.
When the motor will run on its own without heat gun, set the LSN to achive the said 220 degrees, rev the engine with small blips from 8000 - 13000 rpm with the EPA adjusted on your controller. Blip the throttle like this checking temps very often, making sure its getting hot enough to achieve 220 degrees constanty. Keep leaning the LSN out to get the temperature required for good break in.
Run the whole tank of fuel out and then as soon as it stop put the piston on bottom dead centre, very important.
Let the motor cool out for 20 mins totaly.
Grab the heat gun again, and repeat said method. you may need to adjust the EPA on your controller as you go cause it may loosen up more each time it is run. DO NOT OVER REV THE ENGINE, take your time with it.

Run this method for about 5- 7 tanks on the starter box, checking temps constantly, varying the revs and blipping the throttle up and down slowly between that rev range. Cool down the motor in between tanks with piston at bottom dead centre.

Then after you done that, richen up your LSN a little bit and use the heat gun again, start it up and put it on the ground. Run it around on the ground using part throttle for say another 4 - 5 tanks, checking temps often and using minimal rev range.

Most important thing is to get the temps at least 200+ degrees thru out the whole run in process.sticking the body on your car when you drive it slowly on the ground can also help raise the temps, or even use a foil around the head to keep the heat in, I used no foil at all with the breaking but used the LSN to get my temps.

Now that you have run your car around on the ground for say another 5 tanks, then you can reset your EPA to say 50% and keep blipping the throttle . Dont hold your throttle flat out on the end point, just raise and lower the revs smoothly while driving it back to you and checking the temps every say 30 seconds. After a while it will start to loosen up quite a bit and you should richen it up a tad, not alot but enough that you can see smoke coming from the exhaust but it should NOT be pouring out raw fuel from the exhaust stinger.

If you have trouble starting it crack the Turbo glow plug loose anout 1 turn and use your starter box, then tighten it back up as soon as it starts, and you may have to set you idle trim up so it wont stall out on you all the time cause these motors are painfully tight when new.

After about 10 tanks from new i would open the EPA up full and just use bursts on the throttle running it in a straight line. Do not hold maximum revs on the motor for more than 1 second. just bip the throttle to 100% for about another 3 tanks, checking temps very often, richen or lean out to suit so you can always have the temps above 200 degrees.

One thing i will say after all this is, using Run in fuel is BS. you will kill your engine and never get the good performance out of it, you will damage your conrod and also NOT achieve good heat cycling method and i realy dont care if you call BS on what i just typed, its how i did mine and it goes a treat and never lets me down and get awsome milage. They are very tight motors from new but if you take your time in doing what i said and run at least 12 - 15 tanks thru it before you start race tuning it, you will have a very good motor at the end of it. just remember to put the piston at BDC after every tank, straight away.

Hope this helps and everyone has different methods, but as i said if you screw yours up i am NOT responsible KK, got that
-----------------------------------------------

PS: JKA, dont be frustrated if during run in they get real crappy milage per tank, they take ages to loosen up but when they do they go like stink and get great milage. I have put about 10 litres thru mine now its its only just loosened up to how i like it. When new i was getting 5-6 mins per tank, but it gets better believe me.