Aluminum Head Question?
Thread Starter
Racer
Joined: Oct 2010
Posts: 474
Likes: 0
From: Bishop CA
Aluminum Head Question?
Just installed new aluminum heads and now I have a puff of blue smoke that appears when I stick my foot in it or after I shut it off and try to start it. Nothing else has changed with intake, carb and so on. By the way this is on a 75, SBC. Motor only has about 1800 miles on it since rebuild. Before the heads there was no smoke at any time at all. Is something wrong with these heads or could something went wrong with installation. Any ideas will be appreciated.
Thread Starter
Racer
Joined: Oct 2010
Posts: 474
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From: Bishop CA
IK 180 Brodix heads, Edelbrock Performer intake. Also I was told to expect about 50hp gain from the heads. I seem to notice no difference in power. Something doesn't seem right.
Safety Car
Joined: Oct 2005
Posts: 3,570
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From: Algonac Michigan
Le Mans Master
Joined: Apr 2005
Posts: 6,339
Likes: 416
From: Seattle Area WA
Which intake gasket did you use and what cc chambers did you get, unless you bought the 64cc chambers to boost your compression and installed a new cam, you more than likely will not notice any difference.
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Drifting
Joined: Jun 2010
Posts: 1,781
Likes: 15
From: Oxford Ohio
You have good stuff. if the gaskets are as good. Does the smoke have a little sweet smell to it? Were the heads new? What kind of valve seals did you use?
Try a leakdown test and or a compression test and see what the results are.
Try a leakdown test and or a compression test and see what the results are.
Le Mans Master
Joined: May 2006
Posts: 7,708
Likes: 266
From: indy indiana
seals are usually leak under high vacum conditions or after setting awhile,,thus the blue smoke puff at start up. The color blue is always oil btw. white is coolant,black is fuel. I hope you have headers to take advantage of those heads.
Brodix IK 180 heads..either 180 or 200 cc intake ports, 64cc combustion chambers, 2.02(In), 1.60 valves(Ex). 1.25 springs.Sounds like a darn good set of heads. The 50 hp increase ,is of course, compared to what heads? Yep, you may have to cam up to get the 50 hp increase or take it WAY up into rpm ranges I dont want to even think about. 5 grand alot for me tho. yea, check the seals, make sure their the right ones, ect, ect. test for vacum as well.
Brodix IK 180 heads..either 180 or 200 cc intake ports, 64cc combustion chambers, 2.02(In), 1.60 valves(Ex). 1.25 springs.Sounds like a darn good set of heads. The 50 hp increase ,is of course, compared to what heads? Yep, you may have to cam up to get the 50 hp increase or take it WAY up into rpm ranges I dont want to even think about. 5 grand alot for me tho. yea, check the seals, make sure their the right ones, ect, ect. test for vacum as well.
Last edited by ghoastrider1; Jan 24, 2011 at 11:15 AM.
Thread Starter
Racer
Joined: Oct 2010
Posts: 474
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From: Bishop CA
I used all Fel-Pro gaskets , thats what Brodix suggests to use.The heads have 70CC chambers.
Thread Starter
Racer
Joined: Oct 2010
Posts: 474
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From: Bishop CA
The heads are brand new. The valve seals were installed by Brodix.
Drifting
Joined: Jun 2010
Posts: 1,781
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From: Oxford Ohio
Mr. Marzahl is correct, the heads will only flow what the cam tells it to, for the most part. Larger valves will flow more fuel, but they will still only be open as high as your old valves were. Only stay open as long as the old valves did.
That's why roller cams work so well. The lenght of time at full open can be much longer that flat tappet cams.
That's why roller cams work so well. The lenght of time at full open can be much longer that flat tappet cams.
Drifting
Joined: May 2005
Posts: 1,629
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From: Somers CT
I have those heads, they're a great set of heads.
When you said it smokes when you put your foot in it, my opinion it's not valve seals. Are you sure you don't have an intake gasket that's torn or got messed up somehow during assembly?
When you said it smokes when you put your foot in it, my opinion it's not valve seals. Are you sure you don't have an intake gasket that's torn or got messed up somehow during assembly?
Le Mans Master
Joined: Apr 2005
Posts: 6,339
Likes: 416
From: Seattle Area WA
What part number intake gasket did you use, was it the 1256 or 1205 Printoseal gasket, they compress pretty good, did you follow the intake torque sequence? How thick of a head gasket did you install?
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
The others are right on compression....... dished pistons need 64 cc
Thread Starter
Racer
Joined: Oct 2010
Posts: 474
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From: Bishop CA
I used a Fel-Pro 1204 intake gasket and followed all torque sequences. I used a Fel-Pro 1003 head gasket
Le Mans Master
Joined: May 2006
Posts: 7,708
Likes: 266
From: indy indiana
It's your Edelbrock lack of performance intake. I've never understood why somebody would think that a tiny runner and right in the advertisement listing for off idle to some low rpm give them a performance gain.
The others are right on compression....... dished pistons need 64 cc
The others are right on compression....... dished pistons need 64 cc
Le Mans Master
Joined: May 2006
Posts: 7,708
Likes: 266
From: indy indiana
Oh, do a compression check. You have listed two different types of noticing blue smoke. Usually under throttle and blue smoke is noticed, its the rings, start up, its the valve seals..you got me stumped.
Melting Slicks
Joined: Oct 2002
Posts: 2,317
Likes: 111
From: St Louis MO
Sounds like there is leak between the intake manifold and the heads. Pull the manifold and look carefully at the contact pattern on the gasket - both the manifold witness marks and the head's runner contact marks. Something is just not right.
In the same thinking (before you pull the intake manifold), measure the gap thickness between the front china wall of the block to the underside of the manifold - it should be about 1/8". If it's larger than this, especially with heads having larger chambers, say 70 cc, and/or your block is still stock deck height, you may need a thicker intake manifold gasket because often manufacturers don't cut as much off aftermarket heads to create the larger combustion chambers - this causes the runners and the intake manifold bolt holes to be about 30 or 40 thousandths higher than stock. In this case, you should use a thicker intake manifold gasket such as the Fel-Pro Q1245 which is .120" thick to restore alignment, improve clamping and sealing of the manifold.
In the same thinking (before you pull the intake manifold), measure the gap thickness between the front china wall of the block to the underside of the manifold - it should be about 1/8". If it's larger than this, especially with heads having larger chambers, say 70 cc, and/or your block is still stock deck height, you may need a thicker intake manifold gasket because often manufacturers don't cut as much off aftermarket heads to create the larger combustion chambers - this causes the runners and the intake manifold bolt holes to be about 30 or 40 thousandths higher than stock. In this case, you should use a thicker intake manifold gasket such as the Fel-Pro Q1245 which is .120" thick to restore alignment, improve clamping and sealing of the manifold.