ET Report Card on the Speedmaster Heads

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318willrun said:
I love the 2.94's when floating down the road at 60 mph. Car is relaxed which makes me relaxed ! :)
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I went from 2.76's to a 3.23 Sure Grip in my Swinger. Then shortly after I went to a 27" tall 255-60r15 and it killed my 3.23. I need a 3.73 to get back to where I was before. :BangHead::BangHead:
 
When I was in my 20’s I didn’t mind the 4.10’s I had in my heap at all.

35 years later......3.23’s sound much more appealing.
 
PRH said:
When I was in my 20’s I didn’t mind the 4.10’s I had in my heap at all.

35 years later......3.23’s sound much more appealing.
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100% agree. I ran 4.30's, but that slowly worked on me, even in my 20's. I think now with all the cars going down the road at 1400 rpm's, it even makes it seem more intolerable.
 
Yes so much can be won or lost with tire size. Many years ago when my 340 was fresh out of the motor shop I ran an M1 single plane within 850 thermoquad BF ta 265 50 14 they were about 24 and 3/4 inches tall with a 391 rear end and a 509 purple cam it was a match made in heaven but definitely not a freeway combo
 
What, nobody ever run 4.56 or 4.88s like a lot of the the people I know?:lol:
 
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Of course, there's less than a 10 mile radius from home on trips to the 1/2 mile straight away out on the highway, too...
 
Garrett Ellison said:
What, nobody ever run 4.56 or 4.88s like a lot of the the people I know?
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That would be fun until I want to hop in and drive 4 hours north to Mopars in the Park. My 318-2 doesn't need all that gear. It would probably smoke the tires at will even with only 230 horse though. :rofl:
 
Have you ever seen an engine turn white? That's what usually happens before the spark plug wires burn off! :rofl:
 
Garrett Ellison said:
What, nobody ever run 4.56 or 4.88s like a lot of the the people I know?:lol:
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I ran a 383 with 4.56 and a 25" tire . was a nasty daily driver tire fryer. lol
did good with 28" x9 slick at the track though. mid 11 street car
 
toolmanmike said:
Why do you have your 340 out?
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Originally pulled it out thinking it had spun a bearing. But it had not the hillbilly that built the motor did not put the correct washer on the front of the cam and so the fuel pump eccentric was wobbling against the inside of the front timing chain cover making a squealing noise.
Try to make this short. Tore down, I discovered that all 8 of the valve seats were cracked once again the hillbilly had put some 205 or 206 valves in the heads with 11/32 valve stems and blah blah blah anyway all of the seats were cracked so I'm waiting on my new ported 915 heads from Moparofficial and then I will put the 340 Back Together, with it's .060 over 10.5 cr TRW pistons and 508 purple stripe cam and 8 in Turbo action converter.

It is after all A Streetcar.

Right now it has a completely stock 360 with stock heads and stock cam in front of a manual shift 727 and stock converter and 4.88 spool.
 
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Jadaharabi said:
Originally pulled it out thinking it had spun a bearing. But it had not the hillbilly that built the motor did not put the correct washer on the front of the cam and so the fuel pump eccentric was wobbling against the inside of the front timing chain cover making a squealing noise.
Try to make this short. Tore down, I discovered that all 8 of the valve seats were cracked once again the hillbilly had put some 205 or 206 valves in the heads with 11/32 valve stems and blah blah blah anyway all of the seats were cracked so I'm waiting on my new ported 915 heads from Moparofficial and then I will put the 340 Back Together, with it's .060 over 10.5 cr TRW pistons and 508 purple stripe cam and 8 in Turbo action converter.

It is after all A Streetcar.

Right now it has a completely stock 360 with stock heads and stock cam in front of a manual shift 727 and stock converter and 4.88 spool.
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Sounds like you wore it out with all those 4.88 and 5.13 rpm you turn! :poke::poke::rofl:
 
4.56 is nice on the street. always in the 3000 rpm range. lol
4.10 with a 28" tire is what I have now.
 
Glad you got out and had some fun. As many of you know I’m big on telling guys high rpm sucks and isn’t needed. I not only bought but rode the horse. The last 3 months my Duster was on the street I had 5.57 gears in my Duster. Was it worth it. No.
 
I once ran 5.13s in my 70 Charger .


Once....thats all it took ! Even 4.10s made me crazy in that car.
 
When I had my 340 in my car, I ran 5.13’s in it. Track only.
30 x 9 slicks.

It kinda needed 5.38’s for the speed the car was going.
I was shifting at 7500, but barely getting to 69-7000 at the finish line.
 
with a 4-inch stroke with a 410 gear and a 26in tire would be a lot of gear for the street in my opinion but with a 3:31 stroke and a lightened rotating assembly that's a whole different ball game don't you think?
 
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