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 Post subject: Re: 2020 Run-Offs
PostPosted: Wed Jun 20, 2018 5:44 pm 
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Joined: Sun Jan 18, 2004 8:41 pm
Posts: 310
Location: knoxville,tn
Aside from the already mentioned 8 port head the Triumph motor has bigger valves, and a bigger bore, shorter stroke. All better for increasing hp. From the factory a 1296 Spitfire was rated at 75hp while the 1275 Midget was rated at 54hp. So from the factory the Spit made almost 50% more power with the same compression and carbs as the Midget


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 Post subject: Re: 2020 Run-Offs
PostPosted: Thu Jun 21, 2018 10:38 am 
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Joined: Wed Oct 28, 2009 9:24 am
Posts: 806
FP Racer wrote:
I'm going to throw this out. Is anyone running a limited prep 1275 using the mini metro head gasket? When we put this gasket on the full prep 1275, we saw a significant increase in HP. Of course, we also had to switch to a billet 4 bolt center main cap to keep from ripping the blocks apart. Sure, that gasket is expensive, but so is any increase in HP. And that billet center main cap sure did stop almost all crankshaft problems.


Hi Jim -

I'm curious, how does a head gasket change improve power unless maybe by allowing a compression increase via better sealing?

Al Seim
VW HP 1600


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 Post subject: Re: 2020 Run-Offs
PostPosted: Thu Jun 21, 2018 12:04 pm 
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Joined: Sat Dec 12, 2009 8:08 am
Posts: 587
Location: Atlanta, Ga
Al, the 1275 block always had heavy blow by between 2 & 3. The Metro turbo head gasket has a .030 "o" ring built into it and totally seals all the blow by. It was significant and I can not believe none of the limited prep guys hadn't used this. If I were building a limited prep, the head gasket and 4 main Chevy billet main cap would be in my motor. I just found I still have a couple of the original turbo head gaskets. They last almost forever. And somewhere, I've got three or four of the billet main caps.

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Jim Creighton
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 Post subject: Re: 2020 Run-Offs
PostPosted: Thu Jun 21, 2018 2:29 pm 
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Joined: Tue Nov 17, 2009 11:17 am
Posts: 179
racingspridget wrote:
Aside from the already mentioned 8 port head the Triumph motor has bigger valves, and a bigger bore, shorter stroke. All better for increasing hp. From the factory a 1296 Spitfire was rated at 75hp while the 1275 Midget was rated at 54hp. So from the factory the Spit made almost 50% more power with the same compression and carbs as the Midget


That's a bit of an apples to oranges comparison. The 75 hp version of the 1296 was the pre-emissions version. The later, low-compression version of the 1296 was only 68 hp. Likewise, the 54 hp number for the 1275 is for the later low compression version. The early pre-emissions 1275 put out 65 hp. Still a difference, just not nearly as big.


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 Post subject: Re: 2020 Run-Offs
PostPosted: Thu Jun 21, 2018 2:36 pm 
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Joined: Sat Dec 28, 2002 5:14 pm
Posts: 325
Location: galveston, texas
Yeah . I used to O ring my own HG's w/ .030 copper wire from the now defunct radio shack, and the trick was not to bust the small sealing between aluminium and copper firing ring, made tool to lift the mating ring at the hole lay in copper wire and roll back over w/ 7/8 socket , it looked like a coke bottle top when I was done, but you know what, copper coat the bejebers out of it and install, it will crush . time consuming but never had head gasket problems on a full prep tricked out full prep 948, sounds like same thing on the metro gasket.. cheaper than buying them . even was able to re use them. the only HP gain was not blowing the gasket, head gaskets do not add horsepower unless you have a COMETIC sticker on your car ....

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Jeff Peters EX - #03 HP SOWDIV


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 Post subject: Re: 2020 Run-Offs
PostPosted: Thu Jun 21, 2018 6:18 pm 
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Joined: Sat Dec 12, 2009 8:08 am
Posts: 587
Location: Atlanta, Ga
Think what you want. I ran several motors on my Go Power dyno and I know exactly what the pre & post numbers were. And I had the very first one ever done from Richard Longman and I had his numbers. I had no problem spending the dollars to keep all the compression in 2 and 3 vs what you had with a stock or wire "o"ringed gasket.

I have no dogs in the hunt so do what you want, think what you want and have a nice day.

BTW, gaskets and main caps already sold so no more emails please.

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Jim Creighton
CARS Tour DoR
SEDiv SARRC Administrator
V8 Road Racing Series Administrator
Runoffs Line Chief Tech Prod cars


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 Post subject: Re: 2020 Run-Offs
PostPosted: Fri Jun 22, 2018 6:56 am 
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Joined: Wed Nov 04, 2009 7:08 am
Posts: 226
re the Turbo Head Gaskets. I have them in stock. Bill 303-816-0409


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 Post subject: Re: 2020 Run-Offs
PostPosted: Fri Jun 22, 2018 5:12 pm 
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Joined: Tue Aug 20, 2002 12:00 pm
Posts: 27
Location: Moore, SC
Jeff, what happened to your 2nd post? That was good and interesting stuff. Please re-post.
Thanks, Klaus


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