Profile Picture

Milling C1TE heads

Posted By mikeT 3 Years Ago
You don't have permission to rate!
Author
Message
mikeT
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)

Group: Forum Members
Last Active: Last Year
Posts: 39, Visits: 1.7K
Has anyone milled the CT1E heads to say .060" off the decks?
They are posted, and if so , did  you have any issues milling the intake side to compensate? 
MattsY
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)Supercharged (238 reputation)

Group: Forum Members
Last Active: 3 Years Ago
Posts: 82, Visits: 3.6K
I can't say anything about milling the heads that much, but have you considered an offset grind on the crank? That's what I did (3.44" - 3.50") which increases you cubic inches and your compression all while bringing the piston up in the hole. That is of course, if you haven't already decked the block. Even then though, you can run above the deck as long as the top ring doesn't come out if the bore. You can then compensate with a custom head gasket. I know Cometic makes a Y gasket just about any thickness you want, but I remember Ted saying somewhere that there is an issue with their pattern. I believe it was correctable though.
mikeT
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)

Group: Forum Members
Last Active: Last Year
Posts: 39, Visits: 1.7K
That's a thought?   The crank is machined all ready with new bearings.
I really like these engines other that getting compression out of them with out custom pistons, or G heads . Mummert heads are not in the budget for this build.
55blacktie
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)

Group: Forum Members
Last Active: 3 days ago
Posts: 961, Visits: 1.4K
Ted's "One HP..." engine had had .080 milled off 113 heads (posted). Ted said there have been no issues since the rebuild. 
Joe-JDC
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)

Group: Forum Members
Last Active: 2 hours ago
Posts: 710, Visits: 20.7K
I had to mill .050-.055" off my 113 heads to get them down to 70 ccs. after porting.  Held up fine at 10.45:1 compression.  Another set I milled ~.030-.035" for 73 ccs.   I haven't personally ported a set of the C1TE heads, so I can't give you any data on them as far as CCs, or milling.  Joe-JDC

JDC
55blacktie
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)

Group: Forum Members
Last Active: 3 days ago
Posts: 961, Visits: 1.4K
Joe, 113 chambers are supposed to be a nominal 72cc. If .00634 equal 1 cc, your chambers must have been approximately 78 cc before milled, correct? 

I have G heads/w nominal 69 cc chambers. I wonder just how close to my actual target I will come after milling. 
mikeT
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)Supercharged (124 reputation)

Group: Forum Members
Last Active: Last Year
Posts: 39, Visits: 1.7K
Joe could have also done some smoothing or unshrouding work in the chambers . that would have increased the chambers cc . and required more milling to bring them down to 70cc
Ted
Posted 3 Years Ago
View Quick Profile
Co-Administrator

Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)Co-Administrator (12.5K reputation)

Group: Administrators
Last Active: 3 days ago
Posts: 7.2K, Visits: 203.0K
55blacktie (1/24/2021)
Joe, 113 chambers are supposed to be a nominal 72cc. If .00634 equal 1 cc, your chambers must have been approximately 78 cc before milled, correct? 
I have G heads/w nominal 69 cc chambers. I wonder just how close to my actual target I will come after milling. 

In lieu of factory cylinder head combustion chambers having a specification with a target and a ± variance, the term ‘nominal’ is applied.  What that means is that a factory advertised combustion chamber volume will be only in the best of circumstances be as low as that posted number.  Very rarely will the actual combustion chamber size be below that factory ‘nominal’ number but  you will find the cylinder heads that are advertised at a ‘nominal 72 cc’ very often checking out larger than that.  Manufacturing variances come into play on this.  Until you check the combustion chamber volumes, you do not know what you have.  Assume nothing as it will come back to bite you more often than not.



Lorena, Texas (South of Waco)


Joe-JDC
Posted 3 Years Ago
View Quick Profile
Supercharged

Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)Supercharged (1.8K reputation)

Group: Forum Members
Last Active: 2 hours ago
Posts: 710, Visits: 20.7K
Assume nothing when dealing with chamber ccs.  I agree with Ted here.  Any time you install exhaust seats, do a valve job, replace valves, you change the chamber volumes from factory as cast.  Even spark plug tips can cause the ccs to differ.  Porting certainly adds volume to a chamber.  I always get a rough valve job in place before I port a pair of heads, then do the porting, come back and finish the valve job, and then cc the chambers.  Do each end chamber, or all four in each head to get a correct idea of how to mill the heads.  You will need to tell the machinist how many ccs your heads have, and he can then determine how to mill the heads to get the ccs more or less even on the heads end to end.  Usually mill around .006-.0065" for each cc reduction.  Some shops will do the cc measurements for you, if you tell them what you need for final cc figure.  That costs money, but it is the only way to properly build to a specification.  If you don't want to cut your heads unnecessarily, then get the valve job completed, and cc the chambers, THEN order your pistons to get the target compression you want.  Balance everything, and you should be happy with the outcome.  Plan on it taking at least three times as long as you think it should, and you won't get frustrated.   Joe-JDC

JDC


Reading This Topic


Site Meter