Havent seen them on the bay for ages but will have another look.

Thanks

Kevin

A-Main. They are always a good price there.

Was that 148 deg C ? If so, that is getting real hot, too hot.
If it seems to be running ok but is coming in that hot, I suspect you may have fallen into the same trap we have just been talking about - wide idle gap, rich botton, lean top.
The motor will run ok while the tank is full, but when tank level and pressure drops, the motor will run real hot at the end of a tank. The motor will run with the really rich bottom end and overly wide idle gap because you have compensated by leaning the top way too far.
Reset everything to standard - idle gap .7 - 1mm, both needles flush and start tuning from there. If it won't idle at that idle gap, lean the bottom needle until it will idle - do not adjust the idle gap until you have both needles set correctly and the motor running sweet. Then if it is idling to fast or slow, adjust the idle now, then compensate the bottom end needle for any idle adjustments made to bring the tune back to where it was.

If your idle gap and tune is correct, but you have temps that high and are blowing plugs, I would suspect an air leak somewhere.
Don't tune to a temperature, but for reference a well tuned GX (allowing for all the variables like fuel, pipe, track conditions etc, etc) should come in at around 110 - 120 deg C if it's performing well with good smoke at the top end.

No Mate 148 deg f, Idle gap set at 0.7 as you told me and tuned as per mm tips. HSN 3/4 in from flush, lsn 1.5 in from flush.
Thought it was running fine although clutch was a bit worn at end of the final.
have found some plugs on the bay now in UK, helps that i did the search again with the correct spelling lol.
Will get new plugs and try richening the top as Dave said and see how it goes although this time i will do it on a non race day as i can get the engine fully hot, i think the engine set on the bench runs fine but as it is not hot is leaning out over a race causing the problem.
Have definately got the message about the idle setting now lol. I know I have over leaned the top and had the bottom too fat as that advice on machine gunning you gave me was very noticable when i was looking for it and easy to spot,
On the bench i leaned the top end to clear fully throughout the range but have been told to leave slightly rich. I think my mistake has been trying to tune on a race day where you can not heat fully and time is against you.

Hey that's cool Kevin. 148 C would have been just a bit warm :)
3/4 in on the HSN does sound a little far in. We normally find 1/8 to 1/4 turn in on the HSN is plenty for a full race tune with the long needle set up.
To get a real spot on race tune it's an idea to run the buggy for 3 consecutive tanks at race pace and fine tune over this period. The chassis is a very good heat sink, but at race pace the chassis will heat up to a point where it becomes saturated with heat from the motor, and will not accept anymore heat. This additional heat is then pushed back into the motor. This is the point where your motor can overheat. If you tune for this over the 3 continuous tanks, then you can run hard in those longer semi's and finals confident that your motor will not get too hot at any stage.
Tuning on the bench may not give good performance on the track for many various reasons.

Conversly, you may have just had a dud plug :)

Engines run best at 140 c 110 to 120 is still a little cool .. Mind you this all depends on the run in period.

An engine will grow into the condition to which it is run. So it is important that you get it used to what you want from it.

Run a standard head button

Medium cold plug

20% nitro fuel ( depending where you are as to what to run )

2072 pipe

0.4 head shim total.

14T clutch bell

limit the EPA to 50 %

take all un nessesary weight out of the car

run your wing flat

use light weight rims and tyres.

DO NOT IDLE THE ENGINE FOR RUN IN ! Pre heat , start , tune , race.

MASSIVE !

Hmm - 140 C eh :sneaky: Guess that's why I'm not getting those 12 min tanks in my buggy :smile: (but I'm happy with 10 min for now).
Thanks Massive :cool:

yeh I'm with massive..both my MG66 and the 7-port run best around 136ºC...MG66 is running 10 deg cooler since I fitted the CNC head but I'll go back to the standard head now it's cooled down a bit weather wise if the temps are a bit low.

Can I ask what do you mean limit the EPA to 50 % ??

i drove my buggy yesterday to fine tune it,i check my fuel lines,fuel tank for air leaks,sealed the engine with rtv(backplate,carb neck pinch bolt)and start my engine then fine tune my lsn,3-5 seconds on the pinch test,idles consistently with clean acceleration on the box,then put the car on road to tune the hsn but it seems the engine cannot reach its top end on the stretch,at first it will accelerate fast on the bottom to mid,but it has no screaming top end.could it be the clutch shoes worned out that it affects carb tune?

go-7port with 053 pipe

isn't the 053 a bottom end pipe?? try the 2072 or the 086 for the screaming top end or even the 2047(although I think the 2047 will be a bit heavier on fuel).

he means limit the throttle servo travel to 50%..for enduro racing that will limit top speed a bit but you'll get way better fuel economy..

The 053 is a mid range pipe, and back before the GO pipes came out was ideally suited to the 7 Port. I used to run one on my old Gen 4 7 Port and it fair screamed along.
Could be you are a little rich, or a little lean on the top needle, hence the lack of top end power.
Go the safe road by richening it a couple of hours first. If it's worse then go back to where you were and then lean it a couple of hours. You will know straight away if your heading in the right direction.
If you need to adjust the top end either way, make sure you re set the bottom end to compensate.
I doubt it will be clutch related if it's strong on the bottom to mid.

I don't know what temps mine run at, I don't even have a temp gun, I tune to performance and smoke, I spit test it to see if excessive but other than that....... lets just say after a 30-45min final it's pretty warm ;) but no loss of power at or below mid tank at any time durring that time,
(but if that happens then your top end is too lean)

i use to start tuning my engine on the rich side,adjusted it little by little,the engine SOMETIMES accelerates great from bottom to mid and SOMETIMES it misfires on mid SOMETIMES it runs clear on the straight so i was saying it doesnt give me a very consistent response,so i actually took off the carb on my 7port and installed on my nova engine with new clutch shoes on it, the nova runs great without adjusting the go carb on it,runs very clean on the straight,but when i took it back on the go 7port with my semi worn out shoe it really dont run very clearly on the staright even on road.the only thing i want to know if worn out clutch shoes can give you a rich bog?