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Old 06-22-2009, 01:33 AM
  #16  
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Ok thanks guys some helpfull info now.. My search continues.. As always some have never had issues with one.. and some have.. so will keep looking and see if I come across a good deal cheers
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Old 06-22-2009, 07:28 AM
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Originally Posted by ezveedub
I haven't had any MAG heads break. I have bent the top fin on a small edge and the head can compress if landed on on top of, but I have yet to break off any pieces so far.
+1,

one of my mag head has bent fins on top, magnesium is easier to to stress fracture though.

if it breakes then I'll just get the worlds spec2 cooling head.
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Old 06-22-2009, 07:32 AM
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Originally Posted by jamiekerr14
Ok thanks guys some helpfull info now.. My search continues.. As always some have never had issues with one.. and some have.. so will keep looking and see if I come across a good deal cheers
if you plan on pickedup a used one, just remember to ask.

does it comes with ALL the original Carb inserts?

how many head shims was used, and in there now.

my speed with 4gal still has ton of pinch.

these motors are worth their cost, although If I had to get a new one, I'd pick up the Pro-mod Vspec, since it's basically same motor with blue cooling head.
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Old 06-22-2009, 07:50 AM
  #19  
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Originally Posted by JAMMINKRAZY
...But the simple fact is that magnesium doesn't cool as well as aluminum. My point is that an aluminum head engine will run cooler than a mag head engine.
You might be surprised to know that the thermal efficiency of materials used in aluminum and mag heads for RC engines are about the same. The more interesting difference between the materials is the emissivity, which can impact temp readings from an infrared temp sensor. I've run engines with both types of head, and I'm not ready to sign on to the "it runs hotter" bandwagon. The thermal efficiency properties are nearly the same, so there has to be something else. Perhaps the coating isn't machined from the mag head, but it is on the aluminum head. The temp sensor might settle at a different distance with each head, etc. There are a lot of reasons that you might get a differ temp reading, but not any reason I've found that one should actually cool better than the other.
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Old 06-22-2009, 09:02 AM
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Stevep,

Thanks. that's good information to know.
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Old 06-22-2009, 09:16 AM
  #21  
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you can get the new vspec(pro) its supposed to be the same as the mag head but it has the alum vspec head
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Old 06-22-2009, 09:20 AM
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Originally Posted by SteveP
You might be surprised to know that the thermal efficiency of materials used in aluminum and mag heads for RC engines are about the same. The more interesting difference between the materials is the emissivity, which can impact temp readings from an infrared temp sensor. I've run engines with both types of head, and I'm not ready to sign on to the "it runs hotter" bandwagon. The thermal efficiency properties are nearly the same, so there has to be something else. Perhaps the coating isn't machined from the mag head, but it is on the aluminum head. The temp sensor might settle at a different distance with each head, etc. There are a lot of reasons that you might get a differ temp reading, but not any reason I've found that one should actually cool better than the other.
yea a buddy of mine has tha mag head and its never over heated or flamed out,he had it in his truggy it would put the newer speeds to shame...he recently sold it to a newb on the track and he put it in his buggy its the fastest thing on the track and the guy is hard on the throttle and it wont go over 240...mabe they had a bad bach of mag heads idk..but i kno the one i see runs great and its been sold to a newb and still runs great with his tuneing
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Old 06-22-2009, 09:44 AM
  #23  
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Originally Posted by devilchrist
If I had to get a new one, I'd pick up the Pro-mod Vspec, since it's basically same motor with blue cooling head.

It's my understanding that the Pro version doesn't have the Speed (knife edge) con rod in it either.

Brad
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Old 06-22-2009, 09:54 AM
  #24  
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Originally Posted by WYLDTHING
It's my understanding that the Pro version doesn't have the Speed (knife edge) con rod in it either.

Brad
thats not a big diff in performance...but if you rather have it just buy one after break in
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Old 06-22-2009, 09:58 AM
  #25  
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I started running an os speed wc II about a month ago and I love it. It was expensive but I believe that you get what you pay for. I run a 8t 2.0 and the speed has pleanty of power as a matter of fact it flat screams I gear up to 14 cb on larger tracks and it has no problem. I can out pull any racer so far on the straights with no problem. I did install an eb mode head button and I noticed a big improvement. I am getting 10:30-11 min on a tank and I am very pleased with the performance of this engine. Temps are 240's when tuned right. I have just over 2 gallons on it and it has tons of pinch. I do have a buddy who runs a pro twister mod vspec and that engine will give the speed a run for it's money. His RC8 is one of the fastest I have seen. With all the mode the PTM version isvsry very close to the speed and about $150 less. For me I like the bling that comes with the speed, but the PTM is just as strong and it looks identical except the head is blue. The crank has the coatinng, it's balanced, the ceramic bearings are there, the head is cross drilled, the rod has a lot of work done to it, and the head button has been modded so no need to change it. I am sure I missed something but these engines are great. I highly reccomend them. If you have the cash go for the speed. If you want to save a little get the PTM, you will not be disappointed.
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Old 06-22-2009, 09:59 AM
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Originally Posted by reggie l.
thats not a big diff in performance...but if you rather have it just buy one after break in

Well...I believe there is a pretty noticeable difference, and if you have to start buying Speed parts to make your Pro like a Speed, then you might as well just get the Speed....lol.

There is sleeve, stroke, and porting differences between the two engines as well.

It's all in what you like, and how much you want to pony up for a mill.

Brad
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Old 06-22-2009, 10:10 AM
  #27  
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Originally Posted by WYLDTHING
It's my understanding that the Pro version doesn't have the Speed (knife edge) con rod in it either.

Brad
I just got my Pro-Mod and took it apart to seal it up and it has a speed con-rod in it.
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Old 06-22-2009, 10:26 AM
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Originally Posted by bphil49
I just got my Pro-Mod and took it apart to seal it up and it has a speed con-rod in it.
Hmmm.....That's not what one of their full-boat sponsored drivers told me. Interesting....
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Old 06-22-2009, 10:28 AM
  #29  
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Originally Posted by WYLDTHING
Well...I believe there is a pretty noticeable difference, and if you have to start buying Speed parts to make your Pro like a Speed, then you might as well just get the Speed....lol.

There is sleeve, stroke, and porting differences between the two engines as well.

It's all in what you like, and how much you want to pony up for a mill.

Brad
no i still say buy the conrod if it means that much because the motor is still cheaper than tha speed so y not..(but the guy above says that it does have a nife edge sooo......)

and yes there is slight differences between the new speed and the pro..its because the pro is built like the very 1st mag head speed which was a pure power house motor vs the more fuel efficient speeds out after that(not say they dnt have power, but just not as explosive vs the mag head or 1st speeds made)

thats y i think they started making the pro vspec,, so if you dnt realy care about run times and u just want power like the 1st speeds there you go..and its doesnt have a mag head that every one complaind to be a problem
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Old 06-22-2009, 10:43 AM
  #30  
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Originally Posted by reggie l.
no i still say buy the conrod if it means that much because the motor is still cheaper than tha speed so y not..(but the guy above says that it does have a nife edge sooo......)

and yes there is slight differences between the new speed and the pro..its because the pro is built like the very 1st mag head speed which was a pure power house motor vs the more fuel efficient speeds out after that(not say they dnt have power, but just not as explosive vs the mag head or 1st speeds made)

thats y i think they started making the pro vspec,, so if you dnt realy care about run times and u just want power like the 1st speeds there you go..and its doesnt have a mag head that every one complaind to be a problem

Like I said.... it's all in what ya like and how much you want to spend for an engine.

I have a mag head speed, and I have seen a crank from a Pro, and they aren't the same. But, the rod in his Pro that I seen wasn't a Speed rod either, so I don't know what's going on there. Plus, the piston and sleeve in a Pro are just stock V-spec parts that are hand-picked to match better...they aren't the same as a mag head speed either, as far as porting and such.

Brad
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