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will it be absolutely necessary to mill the heads?
#1173157
02/06/12 09:01 AM
02/06/12 09:01 AM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
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Hello everybody,
I have a set of new MP 452 heads in the box(84cc chamber)for my 440 engine.
Using a comp calculator i would get a comp ratio of 9.30 with a .039" gasket.
Well, i sent a mail to Hughes for ordering one of their whisplash cams,and they said to me that 9.30 is too low for aluminium heads and i will need to mill the heads 0.50 or 0.60..
Also said that a .020 gasket is not an option for alu heads.
I,m not very happy about that idea...troubles with the intake fitment,valve clearances etc...
What is your opinion?
Thanks a lot in advance for any input.
Last edited by Coke; 02/13/12 04:11 PM.
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173160
02/06/12 11:35 AM
02/06/12 11:35 AM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
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Lincoln Nebraska
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I'd have the heads' deck milled then set the heads on head gaskets on the block then mockup/set the intake and its' gasket on there & see how far the port/bolt hole alignment is off then another trip to the machine shop to have the heads' intake faces' milled. It's not easy but later on when done & frying the tires cause you got every sub system dead on or near dead on (depending on the system) you'll have forgotten about the time/effort/occaisional aggravation that it took to get you there
live every 24 hour block of time like it's your last day on earth
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Re: will it be be absolutely necessary to mill the heads?
[Re: dogdays]
#1173162
02/06/12 01:49 PM
02/06/12 01:49 PM
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Joined: Jan 2003
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U.S.S.A.
JohnRR
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Quote:
What planet are we on?
Someone help me out here...the only Mopar 452 heads with which I am familiar are cast iron stockers from the late '70s, usually 90 - 92 cc chambers.
I've never associated that number with aluminum heads.
If the refrigerator magnet sticks to them they are cast iron. In that case 9.30:1 is a very usable compression ratio for pump gas.
R.
EARTH ...
MP sells an NHRA stock legal head called the 452 , it's an Ebrock head with straight plugs and a freeze plug in the slab ended head. Since NHRA was allowing outer makes to use it in stock they finally allowed Mopar one also.
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173163
02/06/12 03:31 PM
02/06/12 03:31 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
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I Live Here
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Re: will it be be absolutely necessary to mill the heads?
[Re: dogdays]
#1173164
02/06/12 03:53 PM
02/06/12 03:53 PM
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Joined: Jan 2003
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JohnRR
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Quote:
Well, I'll be dogged!
R.
They have been out for a couple years now , but you have been away from the site ...
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173168
02/06/12 09:58 PM
02/06/12 09:58 PM
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Joined: Feb 2005
Posts: 4,310
Prospect, PA
BSB67
master
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master
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Quote:
Quote:
Well, I'll be dogged!
R.
They have been out for a couple years now , but you have been away from the site ...
Actually, over five years.
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Re: will it be be absolutely necessary to mill the heads?
[Re: BSB67]
#1173169
02/07/12 02:12 AM
02/07/12 02:12 AM
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Joined: Jan 2003
Posts: 74,947
U.S.S.A.
JohnRR
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Quote:
Quote:
Quote:
Well, I'll be dogged!
R.
They have been out for a couple years now , but you have been away from the site ...
Actually, over five years.
I'm screwed either way , I was going to say they have been out for a number or years and then second guessed my self expecting a ... actually they came out last year ...
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173170
02/07/12 08:33 AM
02/07/12 08:33 AM
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Joined: Feb 2005
Posts: 4,310
Prospect, PA
BSB67
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master
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Quote:
Quote:
Quote:
Quote:
Well, I'll be dogged!
R.
They have been out for a couple years now , but you have been away from the site ...
Actually, over five years.
I'm screwed either way , I was going to say they have been out for a number or years and then second guessed my self expecting a ... actually they came out last year ...
Yeah, I did not mean it as nit-picking. When I read yours, I said to myself, "I think its three years", then walked over to my files. Man, the time sure goes, but I belive your point was simply ,...they've been around for a while...., and they certainly have. 
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Re: will it be be absolutely necessary to mill the heads?
[Re: dogdays]
#1173171
02/07/12 08:52 AM
02/07/12 08:52 AM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
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Thanks a lot for all the replies Dogdays, The pistons are flat ,stock style,TRW L2388,1.926" comp distance . The deck is not exactly the same in all the cyls,but they are between .068" wich is the one most closer to the surface and .074" that would be the most deeper in the hole. The Whiplash cam lift is .518". What i thought,or at least what i have read in some web page, is that the Alu heads subtract one pound from the compresion,but they compensate that loss of power in other ways. So if it is 9.30:1 would it go to 8.30:1? Here is a link to Youtube about a 66 Coronet wich is running a very similar set up,440 engine ,Whiplash cam and 452 heads.(The cast iron ones ?)The engine is from a motor-home,8.5 comp ratio and the owner seems to be very happy with it... http://www.youtube.com/watch?v=MjeCyVvg4Ss
Last edited by Coke; 02/11/12 10:00 AM.
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173172
02/07/12 10:49 AM
02/07/12 10:49 AM
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Joined: Mar 2010
Posts: 1,880
Out in Left Field, NY
bobs66440
top fuel
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top fuel
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Out in Left Field, NY
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Quote:
Thanks a lot for all the replies
Dogdays,
The pistons are flat ,stock style,TRW L2388,0.75" comp distance .
The deck is not exactly the same in all the cyls,but they are between .068" wich is the one most closer to the surface and .074" that would be the most deeper in the hole.
The Whiplash cam lift is .518".
What i thought,or at least what i have read in some web page, is that the Alu heads subtract one pound from the compresion,but they compensate that loss of power in other ways.
So if it is 9.30:1 would it go to 8.30:1?
]
The guys here will correct me if I'm wrong, but I think it's not that aluminum lowers compression, but more like you can run more compression with aluminum than an iron head without detonation, all things being equal.
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Re: will it be be absolutely necessary to mill the heads?
[Re: bobs66440]
#1173173
02/07/12 11:29 AM
02/07/12 11:29 AM
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U.S.S.A.
JohnRR
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Quote:
The guys here will correct me if I'm wrong, but I think it's not that aluminum lowers compression, but more like you can run more compression with aluminum than an iron head without detonation, all things being equal.
This is what everything points to .
Coke , with pistons that deep in the hole you'll have no issues with piston to valve interference. but you'll want to be careful with compression being too high without the benefit of quench because of how deep they are in the hole.
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173174
02/09/12 08:28 AM
02/09/12 08:28 AM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
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Quote:
The guys here will correct me if I'm wrong, but I think it's not that aluminum lowers compression, but more like you can run more compression with aluminum than an iron head without detonation, all things being equal.
It seems that they dissperse the heat a lot faster than the iron,wich means that they would evite detonation on a 10:1 and upper CR,but i don,t know what would happen with the power on an engine with less than 10:1.
Quote:
Coke , with pistons that deep in the hole you'll have no issues with piston to valve interference. but you'll want to be careful with compression being too high without the benefit of quench because of how deep they are in the hole.
John,
Do you mean that the compression could damage the gasket triying to scape ?That is the explanation that i find,cause the quench is the flat part of the piston wich leves with the block surface,but this would be on a dish piston,six pack style for example.
However 9.3 or 9.5:1 CR wouldn,t be a trouble,would it?
Thanks both of you
Last edited by Coke; 02/09/12 08:50 AM.
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173175
02/09/12 10:48 AM
02/09/12 10:48 AM
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JohnRR
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Quote:
Quote:
Coke , with pistons that deep in the hole you'll have no issues with piston to valve interference. but you'll want to be careful with compression being too high without the benefit of quench because of how deep they are in the hole.
John,
Do you mean that the compression could damage the gasket triying to scape ?That is the explanation that i find,cause the quench is the flat part of the piston wich leves with the block surface,but this would be on a dish piston,six pack style for example.
However 9.3 or 9.5:1 CR wouldn,t be a trouble,would it?
Thanks both of you
No the compression won't damage the gasket . Your compression ratio under 10 is fine as long as you don't run the lowest octane fuel available .
I'm not getting your question , your english is generally good but I'm a little confused by
the flat part of the piston wich leves with the block surface
is that supposed to read
the flat part of the piston which levels with the block surface ... meaning zero deck ?
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173176
02/09/12 03:01 PM
02/09/12 03:01 PM
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Joined: Jan 2003
Posts: 27,421
Balt. Md
383man
Too Many Posts
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Balt. Md
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I believe Hughes told you that because the aluminum head can run about 1 point higher in comp to be equal with and iron head. So if you run 10.5 with the 452 aluminum head its like 9.5 with the cast iron head. I can tell you we milled the Eddy heads on my sons 400 .040 to get 10.8 comp. It does not have good quench but runs fine on 92 or 92 pump and it has no fitting problems as we milled the intake side .040 also.
Sure you can run the comp at 9.5 but you will have a little better performance if you up the aluminum headed eng to 10.5. You will just loose a tad of power at 9.5. That said I run 10.6 in my aluminum headed 493 and it does have quench and runs great on 92 pump. Ron
Last edited by 383man; 02/09/12 03:02 PM.
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173177
02/09/12 08:12 PM
02/09/12 08:12 PM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
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Quote:
No the compression won't damage the gasket . Your compression ratio under 10 is fine as long as you don't run the lowest octane fuel available .
I'm not getting your question , your english is generally good but I'm a little confused by
the flat part of the piston wich leves with the block surface
is that supposed to read
the flat part of the piston which levels with the block surface ... meaning zero deck ?
Yes youīre right, i forgot the "L". 
No,i didn,t mean zero deck,I just think that i didn,t have a correct idea about what Quench is..
I was planning to use 95 oct gasoline.Here we have 95 and 98.
98 is more expensive but i,m not going to use the car as a daily driver..
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173178
02/09/12 09:35 PM
02/09/12 09:35 PM
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Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck
Not enough dumb comments...yet
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Not enough dumb comments...yet
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
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Quote:
Hello everybody,
I have a set of new MP 452 heads in the box(84cc chamber)for my 440 engine.
Using a comp calculator i would get a comp ratio of 9.30 with a .039" gasket.
Well, i sent a mail to Hughes for ordering one of their whisplash cams,and they said to me that 9.30 is too low for aluminium heads and i will need to mill the heads 0.50 or 0.60..
Also said that a .020 gasket is not an option for alu heads.
I,m not very happy about that idea...troubles with the intake fitment,valve clearances etc...
What is your opinion?
Thanks a lot in advance for any input.
aren't 452's iron? What'd I miss? Some guys use steel shim gasket w/ alum heads..
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Re: will it be be absolutely necessary to mill the heads?
[Re: Mr.Yuck]
#1173180
02/09/12 09:53 PM
02/09/12 09:53 PM
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Joined: Jan 2003
Posts: 74,947
U.S.S.A.
JohnRR
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Quote:
Quote:
Hello everybody,
I have a set of new MP 452 heads in the box(84cc chamber)for my 440 engine.
Using a comp calculator i would get a comp ratio of 9.30 with a .039" gasket.
Well, i sent a mail to Hughes for ordering one of their whisplash cams,and they said to me that 9.30 is too low for aluminium heads and i will need to mill the heads 0.50 or 0.60..
Also said that a .020 gasket is not an option for alu heads.
I,m not very happy about that idea...troubles with the intake fitment,valve clearances etc...
What is your opinion?
Thanks a lot in advance for any input.
aren't 452's iron? What'd I miss? Some guys use steel shim gasket w/ alum heads..
If you read up higher you would have seen we discussed this . About 5 yrs ago MP released a new alum head that I am pretty sure is NHRA legal, it's an Ebrock RPM with straight spark plugs and a freeze plug on the end , they call it the 452.
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173181
02/09/12 10:43 PM
02/09/12 10:43 PM
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Joined: Sep 2005
Posts: 12,481
Chino Valley
RodStRace
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I Live Here
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Quench = the area of the combustion chamber where the flat piston and the flat part of the head are. That would be the left side shown here, ignore the huge bump on the piston.  Octane Your 96 is equivalent to 92 here in the States. US octane is an average of 2 ratings, research octane (RON) and motor octane (MON). If you look at a gas pump in the United States, you will see a yellow sticker that says "octane by R + M / 2" which is the formula for the average. In Europe, they only report the RON.
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Re: will it be be absolutely necessary to mill the heads?
[Re: dogdays]
#1173182
02/10/12 06:32 PM
02/10/12 06:32 PM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
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Quote:
These calculations based on 30 over 440, stock stroke, 84 cc head, flat top piston no valve reliefs nearest piston to deck is 0.068".
Mopar machine work wasn't the greatest and I'm betting your decks are not square to each other or parallel to the crankshaft centerline.
A 30 over 440 has about 914cc swept volume. We would like to have 10.5:1 compression with aluminum heads. To find the volume above the piston required for a compression ratio "r", divide by the quantity (r-1). 914 / 9.5 = 96.2cc. The head volume is 84cc so you need just 12.2cc more than the head. A normal 0.040" composition gasket is about 12 cc so you can see you need to delete some volume somewhere. The steel shim head gasket is 5 or 6 cc so let's say 6. Quite a few guys on this board have used them with success.
So your closest piston is 0.068 in the hole which equals 914 * 0.068/3.75 or 16.6 cc. I suggest cutting 0.035" down from the lowest corner so now all the pistons should be 0.033" down in the hole. You now have 914 * 0.033/3.75 or 8cc which plus the 6 cc of the head gasket and the 84cc head gives you 98cc. (914 + 98) / 98 = 10.3:1. I'd live with that. If you think about it you'll see that milling the block is twice as effective as milling a closed chamber head.
If you use just the steel valley pan/intake gasket with a smear of Hylomar around all the openings the intake should bolt on OK. Then all you have to worry about is valve to piston clearance.
Use checking springs with the valves on one cylinder and check the V/P clearance every 5 degrees from 20 BTDC to 20 ATDC and see what you get. One of the cam manufacturers has the procedure posted.
With 0.052" squish clearance your engine will run very well.
Good Luck!
R.
Thanks a lot Dogdays for all the work that this text involves.
Those formulas are very interisting and useful.
Couriosly ,is the typical theoricaly part that you find boring until you start to find troubles .
To mill the block sound even worse than mill the heads,however i,m starting to belive that this block could have been milled yet,cause i Googled the pistons part number(L2388) and i found a few posts wich talk about people who have used these pistons on 440 blocks and they sit even deeper than mine,such as 0.080 to 0.12 deck.
Last edited by Coke; 02/15/12 04:14 PM.
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173183
02/15/12 05:48 PM
02/15/12 05:48 PM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
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I have meassured the cylinder height from the top of the piston when it is in itīs lowest position in the hole(BDC) to the block surface and i got 3.858". 3.858"-0.070" deck = 3.788" Stroke? I was basing my comp calculations on the standard 3.750"... Am i doing it correctly? Thank again for your invaluable help (And I feel sorry for being so bore  )
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173186
02/17/12 09:52 AM
02/17/12 09:52 AM
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Vitoria, Spain
Coke
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I have measured the block height and there are 270mm (10.6299") between the crankshaft center and the block surface. I have read around here that a 440 block uses to have 10.725" so i suppouse that it has been decked.  Uploaded with ImageShack.us About the rod lenght i have meassured 180mm(7.086") from the center of the pin to the big end center,or the surface were it meets the bearing cap. This is what i don,t understand cause the workshop manual says that the are 6.766" to 6.770"??? The rod "I" beam has the number #1851535 stamped on it. Thanks i advance for any input.  Uploaded with ImageShack.us
Last edited by Coke; 02/17/12 11:48 AM.
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173188
02/17/12 02:04 PM
02/17/12 02:04 PM
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Joined: Oct 2005
Posts: 8,853
Ontario, Canada
Stanton
Don't question me!
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Don't question me!
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Posts: 8,853
Ontario, Canada
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Quote:
The deck is not exactly the same in all the cyls,but they are between .068" wich is the one most closer to the surface and .074" that would be the most deeper in the hole.
Ok, so if you don't get the same measurement for each piston what does that mean??
a) either the rods are unequal length
b) the piston comp. heights are unequal (not likely)
or
c) the decks are not even (most likely)
I would deck the block to get the decks even and straight and run the gaskets you have with the heads as they are.
People talk about milling the intake surface after milling heads but you rarely see anyone suggesting the same after decking a block! Well, decking a block .010 is no different that milling a head .010! But in your case, you're using a gasket which is .020 thicker than stock so in theory you can knock .020 off the "stock" deck measurement or off the head and you'll still be at stock height.
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Re: will it be be absolutely necessary to mill the heads?
[Re: JohnRR]
#1173189
02/17/12 06:05 PM
02/17/12 06:05 PM
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Posts: 340
Vitoria, Spain
Coke
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Quote:
Seriously ??? A tape measure ?
the part number is a stock factory rod there is no way it is that long , you need to use something a little more PRECISE to measure that stuff.
The tape is not enough accurate for most things,i know,just something orientative.The trouble is that i can,t to meassure the rod center to center when it is installed .Just to the pin surface to one of the big end corners. This is why there are that big difference.
However knowing that the rods are the stock ones ,doesn,t work to spend more time meassuring them.
Anyway,the piston travel continues being 3.788"(This time using better than a tape tools ,as you can see in the pictures)
Uploaded with ImageShack.us
Uploaded with ImageShack.us
What i need to know is what meassure i have to use with the comp.ratio calculator, 3.750 wich is the ratio of one crankshaft turn,or 3.788" wich is the travel from BdC to TDC and it depends on piston comp height.
The CR changes depending on wich of both you are using.
Thanks again
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173190
02/17/12 06:09 PM
02/17/12 06:09 PM
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Joined: Jan 2003
Posts: 104,346
Garden Grove, CA
OzHemi
Penguin-hating Ginger
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Garden Grove, CA
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Quote:
Off topic for a moment, but I used to have a Bultaco Sherpa T. 
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Re: will it be be absolutely necessary to mill the heads?
[Re: OzHemi]
#1173191
02/17/12 07:02 PM
02/17/12 07:02 PM
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Joined: Oct 2005
Posts: 8,853
Ontario, Canada
Stanton
Don't question me!
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Don't question me!
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Quote:
3.750 wich is the ratio of one crankshaft turn,or 3.788" wich is the travel from BdC to TDC
Forget the 3.750. You've measured the piston travel at 3.788 and if that is accurate then that is the measurement you must use.
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Re: will it be be absolutely necessary to mill the heads?
[Re: Coke]
#1173195
02/18/12 10:04 AM
02/18/12 10:04 AM
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JohnRR
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Quote:
Uploaded with ImageShack.us
What i need to know is what meassure i have to use with the comp.ratio calculator, 3.750 wich is the ratio of one crankshaft turn,or 3.788" wich is the travel from BdC to TDC and it depends on piston comp height.
The CR changes depending on wich of both you are using.
Thanks again
Did you check push on the piston to see how much it rocks when you are checking it like it is in this picture .
I haven't gone back and read the thread for your specs but I don't think you have too high a compression ratio to even be worrying about this if you are using alum heads .
What was the question again ?
Looking at the pictures the block has been decked , the .006 difference you are seeing is probably the tolerance stack ups. Do you have a good straight edge or have access to a machinists straight edge , check the block to see if it truely is wavy , I'm guessing it's not that bad.
If Hughes says you need higher compression ratio to use their cam and you want to run the engine the way it is then get a different cam. Contact member fast68plymouth and get a cam from him .
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Re: will it be be absolutely necessary to mill the head
[Re: dogdays]
#1173196
02/18/12 10:07 AM
02/18/12 10:07 AM
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Joined: Jan 2003
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U.S.S.A.
JohnRR
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Quote:
The 535 rod is the stock 413/440 rod that is 6.768" C-to-C.
What undersize are your rod bearings?
To increase stroke by offset grinding you have to end up with a smaller rod journal. Unless you are running 0.040" undersize rod bearings I doubt the stroke differs from the standard 3.750.
I think there are a lot of measurement errors that are confusing you.
R.
It is possible for the stroke to be off by that much , the crank in my 383 is 3.370 when it should be 3.375, it is cut .010 under so I don't know who shortened it, the factory or ? The plus side is my pistons ended up at zero deck instead of poking out of the block.
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Re: will it be be absolutely necessary to mill the head
[Re: JohnRR]
#1173199
02/18/12 06:41 PM
02/18/12 06:41 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,376
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Your stroke is off 0.005", his is supposedly off 0.038", that's seven+ times as much as yours. That's why I don't believe his measurements. You could get that stroke by offset grinding 0.040" but the crankpin would be that much smaller then.
So I went back and checked his numbers again. Stated deck height is 10.6299, make that 10.630. The piston compression height is 1.926. That number should be nearly exact. The pistons average 0.071" in the hole. The rods are the familiar LY 535 rods, supposedly 6.768" long c-c.
The crank should be 3.750" stroke which means 1.875 radius.
10.630 - 1.926 - 6.768 -1.875 -0.071 = -0.010"
This means to me that the measurements we got from the OP are accurate except for the "stroke" measurement. Probable causes of the 0.010
" discrepancy are the rods are probably a bit shorter because they've been rebuilt once or twice, the 0.071" down in the hole average is more likely 0.068 and it is possible the crank is a little shorter or the block a little taller than measured.
SO,
1. Calculate your stuff with the published 3.75 stroke.
2. You could stand to take another 0.030 off the block to gain a little more compression. Because your cylinder head is a closed chamber design, you get much less cc reduction cutting the head 0.010" than the block 0.010".
3. Your block has definitely had the deck cut nearly 0.100". This means you're going to have a struggle to get your intake manifold to fit.
4. The Hughes answer on cams and head gaskets was just a cookbook answer. Many board members are using steel shim head gaskets with their aluminum heads. Also, the cam should work fine. I would suggest looking at the Lunati Voodoo line for an alternative.
5. If you just put the engine together like it is it will have decent power and probably run on lower grade gas. Maybe that's all you need?
R.
Last edited by dogdays; 02/18/12 07:09 PM.
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Re: will it be be absolutely necessary to mill the head
[Re: dogdays]
#1173201
02/18/12 07:42 PM
02/18/12 07:42 PM
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Joined: Nov 2004
Posts: 340
Vitoria, Spain
Coke
OP
enthusiast
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OP
enthusiast
Joined: Nov 2004
Posts: 340
Vitoria, Spain
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Thanks Dogem,your answer contains a lot of good info ,cause we are here speaking about CR,strokes,etc but in the end ,the question is always the same : How much Power am i going to loose or how much am i going to gain.
@ Dogdays
The bearings are .010 under
Forget the rods cause it has been my fault.I didn,t make a good meassurement.
@John
Do you mean to push the piston by hand?I have tried it and there is not any clearance..
As you can see the engine has been rebuilt,that is why it is so clean.
It has new rings, main and cam bearings etc The cylinders were also honned and the pistons&rod aligment checked and cleaned with sand.These was a couple of years ago,and it has been on the engine stand since then.
Hughes didn,t said that i need more CR for their cam.It is made for low comp engines.
They said that 9.3 to 1 is too low comp using alu heads,and i should to shave them at least 0.050".
As far for the straight edge i don,t have one,but i don,t think the block is wavy,it was straightened when it was rebuilt(At least is what the bill says) but there is too much diference between cyl decks and it will need to back to the machinist.
@Stanton
I have checked all the cyl decks again.Three times every one (Just in case) using the dial gauge for getting the exact TDC and using feeler gages.
These are the exact decks:
Cyl 1: 0.070"
Cyl 3: 0.070"
Cyl 5: 0.070"
Cyl 7: 0.066"
Cyl 2: 0.062"
cyl 4: 0.062"
cyl 6: 0.062"
cyl 8: 0.062"
What means that you and Dogdays were right.
The driverīs block side seems to be 0.010 higher than the passengerīs one,so i suppouse that a visit to the machinist is going to be a must.
i will ask him for leaving all the cyls at 0.062".
Thanks
Last edited by Coke; 02/18/12 07:50 PM.
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Provided he has the piston to head clearance. If it is a zero deck engine .020-.027 could be flirting with disaster.
