I’d sand roll it a little
My home inspection of Speedmaster heads
- Thread starter 318willrun
- Start date
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I don’t really like that set up either but I do think some mild blending would really help some.
Seeing the plug hiding down in a hole would make you think it would require a different heat range...................But even the Eddy, and now the trick flows.........and i have not heard anyone make any statement about XYZ head needing a different heat range
.100 74.7
.200 140.9
.300 193.5
.400 224.2
.500 242.0
.600 245.2
this is the intake side on our MP iron heads with .547 I 256@.050 cam 13-1 compression 1.96 small stem chevy valve. Pretty basic flat tappet non roller rocker kB piston combo that’ll dip into the 10’s in Vegas (altitude) with a VERY wrong converter. Interesting topic always.... carry on!
jay
.200 140.9
.300 193.5
.400 224.2
.500 242.0
.600 245.2
this is the intake side on our MP iron heads with .547 I 256@.050 cam 13-1 compression 1.96 small stem chevy valve. Pretty basic flat tappet non roller rocker kB piston combo that’ll dip into the 10’s in Vegas (altitude) with a VERY wrong converter. Interesting topic always.... carry on!
jay
Nor have I heard of anyone doing anything different about it. Let's be fair, people have been running OOTB Edelbrocks for a lot of years now, and no issues reported? Hmmmm……
P.S. - I just ran a plug in mine, and of course the same results...
I think on these that something should be done. That’s just to far in for my liking. Sand roll as stated or a light dressing with a Dremel and carbide bit? Or is that to aggressive? Kim
I guess I'll see what some here come up with. I don't think SM is any worse than the Eddies. Not saying it's right, but people have been bolting on OOTB eddies for 25 years ?? Not one issue reported due to plug location to my knowledge
The picture I just posted above of my Edelbrock heads went 9.70’s at 2800 pounds. I will be making some mods with a carbide burr and sanding roll before they go on my next build.
Agree, it’s just there’s two ends of the spectrum (install ootb and full tilt porting job) but a massive expanse between where anyone can do from just a little to a lot more. This is simply an attention to detail issue and an easy cleanup job at that. If you had your choice of an early version and latest version of these heads and a nice dressing to the hole was the difference, what head would you rather have ootb?
but you ran them like that for a while, correct? for sure there is opportunity for improvement, but certainly we are not the first to discover this.... Can't be ..
Can wait to see ur results PBR. Kim
I have small sand rolls for my Dremel..... I could make quick work out of the last few threads in the spark plug hole....
Heck ya I’ve been running it like that for over 5 years. I have an msd 7 but especially with the volume of alcohol I will be addressing this ASAP. ET is ET and I love cheap ET.
Id knock the ground strap off a plug, install it, then contour and polish the hole with a coarse sanding roll and not worry about rounding the threads deeper in.
A end mill in the Bridgeport might be in order. I would rather see material taken out of the plug seat than out of the chamber.
lol.... before I read this I already knocked the strap and porcelain from the end of the plug. I think I'll just remove the threads that are remaining. Might go to work right now....
I only noticed those edges when I gave my set a thorough rectal exam. Then when I got the TF’s I noticed the detailing so no, somebody else has been there.....well versed in being up to their elbows likely hitting teeth
There may be other things to consider.
I'm just spitballing here but i can see the plug needing some kind of protection.
Now stay with me here. what if there was some kind of Wet Flow situation were fuel would puddle in that area and so they made a hat, so to speak so the fuel rolled on by, instead of puddling. now if you moved the plug out more like toolmanmike suggest......................just thinking out loud here........
No matter what, i would be removing any sharp edge from the combustion chamber!
I'm just spitballing here but i can see the plug needing some kind of protection.
Now stay with me here. what if there was some kind of Wet Flow situation were fuel would puddle in that area and so they made a hat, so to speak so the fuel rolled on by, instead of puddling. now if you moved the plug out more like toolmanmike suggest......................just thinking out loud here........
No matter what, i would be removing any sharp edge from the combustion chamber!
TOO LATE!!!! AREADY STARTED, LOL..... I'll post my results in a few... LOL.I only noticed those edges when I gave my set a thorough rectal exam. Then when I got the TF’s I noticed the detailing so no, somebody else was already up to their elbows likely hitting teeth
PRH
Well-Known Member
As has been mentioned...... these are copies of Ede heads.
The plug holes are done that way in the RPM heads, and since that’s the head they copied...... the threads are the same in the SM heads.
My guess is over 95% of the sets in use have not had anything done to the plug holes.
The plug holes are done that way in the RPM heads, and since that’s the head they copied...... the threads are the same in the SM heads.
My guess is over 95% of the sets in use have not had anything done to the plug holes.
5 minutes...… What ya think??? Didn't want to get carried away... 35 more minutes to do the other 7, is it worth it?
I would thing they should look more like this.....
stixx
Well-Known Member
Now round off the corners and be done...
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