Author Topic: Easy ways to increase compression ratio?  (Read 6509 times)

Offline jimynick

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Re: Easy ways to increase compression ratio?
« Reply #15 on: February 04, 2013 - 11:05:52 PM »
What the real easy way is, is stick a 360 in it and have done. By the time you add up the cost of pistons, rings, bearings, gaskets, valve job, machining, etc. You're cheaper off to find a decent used 360. It'll bolt in the same hole, to the same trans and if you're really on a budget, you could re-use the 318's manifolds if the 360 isn't a Magnum version. Just my  :2cents:




Offline mildphil

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Re: Easy ways to increase compression ratio?
« Reply #16 on: February 05, 2013 - 06:00:18 PM »
Yeah, I guess there is no real cheap way. I will probably save up some cash then when the time comes I will throw in a rebuilt 440.
Nothing last forever, so be thankful for what you have while you still have it. :)

Offline 73restomod

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Re: Easy ways to increase compression ratio?
« Reply #17 on: February 07, 2013 - 10:30:26 PM »
You could get a thinner head gasket as an ultra cheap route, but getting your heads and intake shaved doesn't cost all that much if you find a good machinist with reasonable prices.
1151G Mr. gasket head gasket Compressed Thickness .028 plus a .030 head cut should get you close to 1 full point of compression. If you do the wrench work yourself could be done easily for under 300 Bucks.

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« Last Edit: February 07, 2013 - 10:39:37 PM by 73restomod »

Offline cudabob496

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Re: Easy ways to increase compression ratio?
« Reply #18 on: February 08, 2013 - 12:44:32 AM »
You could get a thinner head gasket as an ultra cheap route, but getting your heads and intake shaved doesn't cost all that much if you find a good machinist with reasonable prices.
1151G Mr. gasket head gasket Compressed Thickness .028 plus a .030 head cut should get you close to 1 full point of compression. If you do the wrench work yourself could be done easily for under 300 Bucks.

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true, but should probably check valve to piston clearance at same time.
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

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Offline jimynick

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Re: Easy ways to increase compression ratio?
« Reply #19 on: February 08, 2013 - 11:09:19 PM »
true, but should probably check valve to piston clearance at same time.
Especially as you're going to re-cam it!

Offline Chryco Psycho

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Re: Easy ways to increase compression ratio?
« Reply #20 on: February 09, 2013 - 09:04:23 AM »
the "easiest" way to increase cylinder pressure is a Blower or Turbo !!

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Offline cudabob496

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Re: Easy ways to increase compression ratio?
« Reply #21 on: February 09, 2013 - 07:29:48 PM »
the "easiest" way to increase cylinder pressure is a Blower or Turbo !!

or nitrous oxide?
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline mildphil

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Re: Easy ways to increase compression ratio?
« Reply #22 on: February 10, 2013 - 12:06:28 AM »
Haha if only I had enough money for both!
Nothing last forever, so be thankful for what you have while you still have it. :)

Offline cudabob496

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Re: Easy ways to increase compression ratio?
« Reply #23 on: February 10, 2013 - 03:18:17 AM »
neat article in the new Hot Rod. Vic Edelbrock Sr was the first man to put nitromethane in a race car. No one knew why
he kept winning. All they knew were flames kept coming out of his exhaust. The first time he tried it, his engine
melted in areas!
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline mildphil

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Re: Easy ways to increase compression ratio?
« Reply #24 on: February 10, 2013 - 12:47:10 PM »
Wow.so what made him even want to try that? Just a lucky guess?
Nothing last forever, so be thankful for what you have while you still have it. :)

Offline HP_Cuda

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Re: Easy ways to increase compression ratio?
« Reply #25 on: February 10, 2013 - 12:51:40 PM »

I'd say nitros first then blower/turbo but then again with nitros you have to make sure you have fuel pressure to not lean it out.

the "easiest" way to increase cylinder pressure is a Blower or Turbo !!
1970 Cuda Clone 440 4 speed - sublime green
1970 Cuda 383 4 speed - yellow - SOLD

Offline Chryco Psycho

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Re: Easy ways to increase compression ratio?
« Reply #26 on: February 10, 2013 - 09:01:40 PM »
Nitrous Oxide just adds more oxygen to the mix requiring more fuel to keep the burn temps down , think oxy act torch , more oxygen = more heat .
 Nitromethane is totally different , i carries oxygen in the fuel , the engine is close to hydraulic locking there is so much fuel pushed in , the flames from the exhaust is the oxygen being burned in the air from the heat coming out of the exhaust

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Offline jimynick

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Re: Easy ways to increase compression ratio?
« Reply #27 on: February 10, 2013 - 11:07:47 PM »
I'd suspect that Vic Sr. may have been the first American to use nitro, but the Europeans were screwing around with exotic fuels big time in the 30's and if I had to bet, I'd bet it was them, first.  :2cents:

Offline HP_Cuda

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Re: Easy ways to increase compression ratio?
« Reply #28 on: February 10, 2013 - 11:10:40 PM »

I wasn't speaking of nitromethane at all. In fact if you want to talk about N0S:

When N2O breaks down in the engine's combustion phase, there is an additional benefit to performance: the oxygen atoms in N2O, as they are freed from their bond to the nitrogen atoms release heat in an exothermic reaction, i.e. one producing more heat than was required to initiate the breakdown; contributing to the overall power increase. The additional amount of heat produced, like that achieved above by increasing the charge of fuel allowed, by use of "nitro," similarly increases engine efficiency and performance, which is directly related to the difference in temperature between the unburned fuel mixture and the hot combustion gasses produced in the cylinders.
1970 Cuda Clone 440 4 speed - sublime green
1970 Cuda 383 4 speed - yellow - SOLD