Slant Six Forum
https://slantsix.org/forum/

horse power gains
https://slantsix.org/forum/viewtopic.php?t=33384		 Page 1 of 1
Author:  theslantingsix [ Mon Jan 19, 2009 8:17 am ]
Post subject:  horse power gains
what kind of horse power can i expect over stock with the erson 270 cam
Author:  Joshie225 [ Mon Jan 19, 2009 8:30 am ]
Post subject: 
The HP gain depends greatly upon other modifications you have or will undertake at the same time as the cam swap.

Things I would do before swapping cams:

2 1/4" exhaust
2bbl or 4bbl intake and carburetor
electronic ignition with recurved distributor
compression ratio check and correction (it is almost certainly lower than you think)
ported head with larger valves
torque converter and/or rear axle gear change

I've made the mistake of throwing a big cam, 4bbl carb, intake and headers at a low compression engine with a lousy timing curve and 2.76 gears. It's easy to spend money and end up with some fancy parts and a slow car.
Author:  wvenable [ Mon Jan 19, 2009 9:14 am ]
Post subject: 
Josh, that is a great checklist. Even though I have learned quite a bit (and still learning) that helps put things in perspective. Thanks.
Author:  theslantingsix [ Mon Jan 19, 2009 10:08 am ]
Post subject: 
well i was just wondering how much horsepower over stock cam but yall dont worry i got shorty headers, offy intake. and 390 holley on the way and a bunch of head work in mind but i was wondering that becouse im geting the cam in my engine rebuild kit so i was just thinking about what i could get out of it and im geting the kit basicly for what the machine shop gets it for
Author:  Joshie225 [ Mon Jan 19, 2009 10:47 am ]
Post subject: 
The Erson 270 would be a worthwhile upgrade considering you have all the other equipment to support the increased cam duration. I would shoot for a 9:1 compression ratio, make sure the advance curve is tailored to the engine (and car) and don't run too tight a torque converter or to numerically low rear end gears. A bad muffler will also kill performance and good ones don't have to be loud.
Author:  theslantingsix [ Mon Jan 19, 2009 11:11 am ]
Post subject: 
i dont think a toruqe converter would help me with a manny tranny, but i could go with a taller gear ratio i got a 3.21 to one right now which i would like to keep if possible, and i like my cherry bombs
Author:  1974duster kev [ Mon Jan 19, 2009 12:27 pm ]
Post subject: 
Well i figure this oughta give you an idea since my build is similar.
i ran 11.9's in the 1/8 with a cliff intake 4bbl 390 cfm/ shorty headers.

then after i built my current motor compression high 9's close to 10 maybe. 270 erson cam stainless oversized valves with headwork stock crapola dist. stillm I ran like 10.3's out of the box.
got it down to 9.9's with no other money spent just tinkering

Kev
Author:  DusterIdiot [ Mon Jan 19, 2009 6:54 pm ]
Post subject:  What he said and....
Quote:
but i could go with a taller gear ratio i got a 3.21 to one right now which i would like to keep if possible, and i like my cherry bombs
Already an OK combo... I would shoot for a bit more than 9...like the 9.2:1 'tops', and the mods Joshie already lined out would be good for about 160HP+ at the crank...actual testing will tell (dial it in and do a couple rounds at the track...). All of that and a good distributor curve will give you the best results...

3.55's and a 3 speed aren't the 'best' combination...(there are times on the highway where I'm glad that I have an OD gear to lower the rpm...believe me...)

Good Luck,

:wink:

-D.Idiot
Author:  theslantingsix [ Tue Jan 20, 2009 6:34 am ]
Post subject: 
ok so how much off the head would .045 do it or .090 dont want it to high couse then you have to pay for more expencive gas
Author:  Doc [ Tue Jan 20, 2009 9:49 am ]
Post subject: 
You will need to measure the piston to block deck height" and the head gasket thickness in order to calculate the engine's compression ration... any other way is just guessing.
DD
Page 1 of 1 All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/