A
Anonymous
Guest
Havent figured my compression ratio (exactly) yet on my new engine but the block is decked .040, flat top 2.3 hsc pistons set at 0 deck height, .027 compressed thickness Ford head gasket, head milled .080 with a combustion chamber cc at 54 cc's
Total timing is 38 degrees at 2800 rpm's.
Premium gas and alcohol/water injection is a must have!
We'll see what happens!
A couple of years ago I was running 11.6:1 with water injection and some hardware store octane booster...ran pretty good!
Later,
Doug
Total timing is 38 degrees at 2800 rpm's.
Premium gas and alcohol/water injection is a must have!
We'll see what happens!
A couple of years ago I was running 11.6:1 with water injection and some hardware store octane booster...ran pretty good!
Later,
Doug
A
Anonymous
Guest
What I would like to see is your water injection setup.
-Chris
-Chris
A
Anonymous
Guest
I'd be more comfortable if the cam mfg. admitted that higher compression can only restore the cranking pressure, but never the low speed power.
As it is now, we're left with 2 choices:
1. they don't know (not likely), or
2. they do know, and they leave it out because it might affect sales.
As it is now, we're left with 2 choices:
1. they don't know (not likely), or
2. they do know, and they leave it out because it might affect sales.
LEROY POLL
Well-known member
HEY PANIC
.....MY VOTE IS FOR #2....!
.....THEY ALWAYS SAY CHANGE YOUR REAR END TO A BETTER RATIO SO THE MOTOR WILL BE IN IT'S RANGE!!!! THAT = LOSS OF LOW END... FROM THE CAM!!!
LIVE IN GRACE
LEROY POLL
.....MY VOTE IS FOR #2....!
.....THEY ALWAYS SAY CHANGE YOUR REAR END TO A BETTER RATIO SO THE MOTOR WILL BE IN IT'S RANGE!!!! THAT = LOSS OF LOW END... FROM THE CAM!!!
LIVE IN GRACE
LEROY POLL
Hey Panic, that point 2 is the one!
You're right. Just adding compression to make up for bleed off isn't the whole answer at all. What I know is that the duration at which both intake and exhasts are open 30 to 50 thou should be minimised. There are pattern cams that can be better than stock cams in this respect, but still go up in duration 20 to 30 degrees at lash.
A good example from the old days was the Isky 134 cam used in 2.0 and 2.3 Pinto OHC engines. It was perfect for auto matics becasue you got big power increases with no loss in low end driveablity/tractorbility. David Vizard commented that he got a 68% power boost, better millage, emissions and drive with a big vave head, Holley 350, 134 cam, and C4 auto in his Pinto.
Main reason as the stock cam and head were so badly matched!
As for compression, this is the engine that got a very high compression ratio that he ran on the street with his unpatented Anti Detonation Injection. Remember, stock 2.0 liter Pintos ping there bleeding heads off with 87 octane, and yet he ran 91 octane on 12:1 comp.
If the stock engine is badly matched, the right cam won't hurt the low-speed drive. In 90% of the cases, the details are not on the cam makers lists/ What worries them is the auto, a/c, p/s, power braked stock comp engine with oversized tyres and a tall diff with a big 270 degree cam. There aren't many cams that size that can work without killing the low end. You won't be able to tell which one is good or bad off the cam tag, the full cam plot at per degree is needed.
Back to the octane ratio requirement, I guess.
Looks like its time to run the 22 inputs panic metioned into a hat, and do the democratic numbers game on predicting knock.
I've done it with power ratings, time to do it with knock. I use this Stereo-Net analysis for curly geological and stability problems. What you do is give each of those 22 data inputs a fraction rating, starting with 1 out of 4.5 for each. A perfect engine would score 100 points. The worst possible is 22. You do a look-up table for what octane sensitivity is. A side valve 1953 Ford 239 might score, say, 35. A Hemi or Jag HE V12 may be close to 100.
You start off with the engine being perfect, and then vote out the bad factors. You just change the factional amount when the results don't compute on a range of engines. I'll start with a stock auto 2.78 geared 250 Granada, then an auto 2.77 geared 250 Cross Flow Falcon, then a 3.45 auto Pinto 2000, then an cammed up auto Pinot 2.0 like Vizard ran. I've got all 22 bits of data for these engines, so its not like needle in a haystack stuff.
Hopefully, this will give an idea of octane sensitivity.
Thats a challange I like!
You're right. Just adding compression to make up for bleed off isn't the whole answer at all. What I know is that the duration at which both intake and exhasts are open 30 to 50 thou should be minimised. There are pattern cams that can be better than stock cams in this respect, but still go up in duration 20 to 30 degrees at lash.
A good example from the old days was the Isky 134 cam used in 2.0 and 2.3 Pinto OHC engines. It was perfect for auto matics becasue you got big power increases with no loss in low end driveablity/tractorbility. David Vizard commented that he got a 68% power boost, better millage, emissions and drive with a big vave head, Holley 350, 134 cam, and C4 auto in his Pinto.
Main reason as the stock cam and head were so badly matched!
As for compression, this is the engine that got a very high compression ratio that he ran on the street with his unpatented Anti Detonation Injection. Remember, stock 2.0 liter Pintos ping there bleeding heads off with 87 octane, and yet he ran 91 octane on 12:1 comp.
If the stock engine is badly matched, the right cam won't hurt the low-speed drive. In 90% of the cases, the details are not on the cam makers lists/ What worries them is the auto, a/c, p/s, power braked stock comp engine with oversized tyres and a tall diff with a big 270 degree cam. There aren't many cams that size that can work without killing the low end. You won't be able to tell which one is good or bad off the cam tag, the full cam plot at per degree is needed.
Back to the octane ratio requirement, I guess.
Looks like its time to run the 22 inputs panic metioned into a hat, and do the democratic numbers game on predicting knock.
I've done it with power ratings, time to do it with knock. I use this Stereo-Net analysis for curly geological and stability problems. What you do is give each of those 22 data inputs a fraction rating, starting with 1 out of 4.5 for each. A perfect engine would score 100 points. The worst possible is 22. You do a look-up table for what octane sensitivity is. A side valve 1953 Ford 239 might score, say, 35. A Hemi or Jag HE V12 may be close to 100.
You start off with the engine being perfect, and then vote out the bad factors. You just change the factional amount when the results don't compute on a range of engines. I'll start with a stock auto 2.78 geared 250 Granada, then an auto 2.77 geared 250 Cross Flow Falcon, then a 3.45 auto Pinto 2000, then an cammed up auto Pinot 2.0 like Vizard ran. I've got all 22 bits of data for these engines, so its not like needle in a haystack stuff.
Hopefully, this will give an idea of octane sensitivity.
Thats a challange I like!
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