will I have to have the intake milled to match the amount removed on the heads and the block, the heads have had 18 thousandths removed, the block had 5 or 10 thousandths, is that enough to make the intake not get a good seal to the heads? and require milling of the intake?:

 

it will probably be ok, but just do a "dry run" before you lay sealant down to make sure.

 

I had my heads milled .030, I didn't touch the block deck, and my intake did not bolt up. It was close, but just enough off to where I needed to enlarge the intake holes a little. And yes, do what Jordon did and do a "dry run" with the intake, I didn't, and I had to scrape off all the silicone I just put on

 

My heads are milled a lot. I actually had to take .080 off the intake. If you grind the holes, you are only making the holes fit. The intake ports probably don't line up. Now, mine line up perfectly. You can get a small mirror inside the intake and see if they line up or not.
Todd

 

Combustion deck removal amount x 1.2 = material to remove from the intake port side of head or the from the intake port deck of the manifold.

Combustion deck removal x 1.7 = material to remove from intake manifold rails front and rear.

So if a 0.010 mill on the heads then 0.012 should be milled from the intake side(head or intake) for a perfect fit. Also, the front and rear intake rails should be milled 0.017

Jeff D.

 

Would this be .012 on each side of the intake? Or .006 on each side? I think I know the answer but would want to make sure before I mill on the intake.
Thanks

 

its "Strange" that so many people want to mill the Intake Manifold
"instead" of milling the Intake sides of the Cylinder Heads ??

whoever milled the deck surfaces of the Cylinder Heads...should have milled the Intake sides of the Cylinder heads the correct amounts and angle for perfect fit !

if you mill the intake manifold ..that intake manifold now becomes "dedicated" to those particular set of heads !
it will then become hard to resell that Intake to someonelse
or tryout a different Intake on the Dyno or DragStrip without first milling the new Intake also

at the most , only the front and rear intake manifold rails would be milled if for some reason the machinist after he decked and squared the block, didn't mill the front and rear rails of the block for the correct intake manifold fit in that area.

when i deck and square mill a Block, i always automatically mill off .060" off block's front and rear rails

when i mill heads more than .020" , i mill the intake sides
to correct the fit and check the angle or correct it at the same time

 

MaxRaceSoftware

I am a little to far in the build to go back now. The motor is asembled and in the car. This is also my first motor that I have built. So I do understand what you are saying and will make sure the next build up Is done right now that I have more knowledge about how to do it the right way.
But the current problem I have is the block has been decked .008 and the heads have been milled .030 Is it safe to say I need .046 milled off each side of the intake port side and .065 of the front and rear of the intake? I not really worried about dedicating the intake to those heads. You can buy the intake used for about 75.00 It would be more expensive now to go back and fix what the machine shop skimped on.
Thanks for the information

 

yes, .046" off sides and .065" off rails should work great

watchout the headgasket upper ends in manifold rail corners from intereferring with fit, might have to bend down or snip excess

use Silicone on rails, right after applying about a 1/4 high bead , very quickly install intake..don't give the silicone a chance to cure yet.

$60 to $90 should be ball park price, as you have to "setup" the intake mutiple times in the Mill ..anything less than $60.00 would be a very good price

i have fixtures that finds the exact angle of the V and determines where the bolt hole centerlines should be on both sides

just yesterday, i had to use the fixture to correct all the intake bolt holes on a brand new Edelbrock RPM Air Gap intake that had all the holes on 1 side a half of hole off...the guy purchased the intake and couldn't bolt it on

the V angle was perfect and 1 side

 

MaxRaceSoftware

Thanks for the information you have been extremly helpful.
Cliff

 

i have fixtures that finds the exact angle of the V and determines where the bolt hole centerlines should be on both sides

just yesterday, i had to use the fixture to correct all the intake bolt holes on a brand new Edelbrock RPM Air Gap intake that had all the holes on 1 side a half of hole off...the guy purchased the intake and couldn't bolt it on

the V angle was perfect and 1 side
========================================

OK , thanks Cliff929

just a side note=> i usually only fix bolt hole locations and angles a couple of times a year, overall intake manifolds produced are pretty good in quality

i had a rash of Edelbrock Victor Ram tunnel ram intakes that had the distributor hole off by over 3/8 inch + on 4 intakes, years ago .

also some of the newer intakes are coming with slots instead of round holes...so the fixture makes it easy to findout where the bolt hole CenterLines CL should be when you go to scribe your port layouts and gasket dimensions

 

MaxRaceSoftware

You have a PM message
Cliff

 

Thanks for the calculations Poorman, you managed to pre-answer my question nearly a year in advance. The search function can be a dangerous thing.

Also if anyone reads this, I'm gonna go out on a limb and say if I took .025 from the heads, .026 from the deck, and went with a .039 head gasket as opposed to the .049 stock gasket, I would take .0732 from each side of the intake and .1037 from the front and rear intake deck.

 

MaxRace,
I will be adding used LT-4 heads that have been ported(GTP) to a stock shortblock. I plan on using the LT-4 head gasket (.043") and milling the heads approx. .006 just to clean them up. Should I worry if the local machine shop doesnt want to mill the intake side? Thanks in advance. Ken

 

Anyone?