RE: Hurricane Xp engine temperature
thats interesting hey. I am very supprised that a larger head didn;t give you any extra cooling what so ever. Is it possible there was a leak which would have artificially leaned out the engine which would counteract the temp? Ie. the temp stays the same? Just a theory. What brand head were you using? Nova raceheads are significantly different from Amercian CNC.
To me it seems logical hey that you get cooler temps with a larger head. But obviosuly thats not the case in every situation. It was only stated as dropping temps by about 40F I think but In my case its more like 90F!! When I first used it I was immediately concerned that it was perhaps now too low in temp so I spoke with the GM. Not really knowing who he is exactly he said that he had several nitros and they all ran similar temps & he had been running them at those temps without any problems for years.
This head i found was just a gamble to be honest. I thought the sirio 27 looked almost the exact same mill. They gave me the hole dimensions & everything lined up ok and bolts on perfectly I found. I think there are other heads that will fit too.
Now as you mention there are other factors like climate, leaks, nitro% etc & I'd agree there too. Its cooling down here and I am considering swapping back the stock head over winter as its so dam hard to start when cold. The above temps I was getting was whilst its been warm so I think it may get too cold outside now to use the larger head. At first we thought the engine was leaking somewhere but the engine has been checked about 3 or 4 times and everything seemed in order. Incidently I am using 15% nitro which may account for higher temps than if I was using say 25%. I have also found that the team infinity & team orion use the same mills & the .27 s are apparantly identical to the orion wasp. The orion wasp operates at 270F running temp so its not supprising the infinity acheives similar temps in the first place. Other engines like novarossi seem to operate at low temps like 230F eliminating the need of a larger head.
A few things to note generally about the larger head & the temps achieved, would be the fact as I mentioned before is that the temp gun I have is now about an inch further back and this could significantly distort the reading. I suppose if I put a smart temp probe on it may give a more accurate reading. The temp gun is reading the head temp not necessarily the engine temp I think perhaps.
This head is also made of the lighter alluminum alloy and apparantly its best property is that it disapates heat much quicker than other heavier alloy heads available. The denser alloy absorbs heat better but the downside is that it doesn't disapate the heat effeciently as the lighter alloy head. The other good thing is that in the event of a bad rollover the head is more likely to just rip off without damaging the rest of the engine. Well thats the theory anyway.
In any case with such low temps with this head, i certainly wouldn;t run a new engine in with it. I still think you need to heat cycle a new engine well when running it in with the stock head first.
But yeah i certianly wouldn't say they're a band aid fix though. If an engine runs normally at say 280F and you want it at say 230F, putting a larger head on is hardly a band aid. It greatly reduces engine wear & massively increases the life of the engine amongst other things. Preventative measures I would have thought?
And when it comes down to it, have you ever heard of anyone killing an engine by running it too low in temperature? I certainly haven;t!
Cheers guys