Head Identification

[belize1334]

I've got a head here that I'm considering rebuilding and I can't figure out what it came from. Key features:

1g style intake ports
1g style t-stat
1g style cam gears
12mm stud holes (drilled out from 11mm?)

2g style exhaust studs
"G6/12" casting about t-stat

My understanding is that all 6-bolt heads have a number cast into them (i.e. "16", "18", "20", etc). Later 2Gs have either "G6/5" or "G6/15". I can't find a single reference to a "G6/12" head. And the larger 2g exhaust studs are very confusing... I'm currently thinking that it's a 1g 7-bolt that has already been drilled out for 6-bolt studs. Any ideas?

 

[theevozero]

Dsm 6 bolt heads have "2.0" cast into the head, 1g 7 bolt say "G6", 2g say "G6k" on early heads and "G6S" on later heads. As far as what the colt gt and evo's have cast on them, I'm not sure.

 

[prove_it]

Send BogusSVO some pics and he will tell you.

Are the intake runners smooth from porting?

Also I have 2g style exhaust studs. It's a common upgrade to prevent manifold flange warping and better gasket sealing.

 

[BogusSVO]

Sounds like a 1g/6bolt head now.

The casting number never has ment much to me, these heads get swapped around more than a SBC head.

As far as having the 10mm corner exhaust studs, I get requests for that mod on heads, I have done 20 heads or so like that since the 2g E mani is better than the 1g.

What you need to look at is head thickness and cam tower warp, about anything else can be fixed or modded to fit your build.

Also some of the 7 bolt/1g heads had the bosses for the front mount cam sensor.

 

[GSTwithPSI]

Picture of the 10mm head stud mod done by Dale /ubbthreads/images/graemlins/grin.gif

 

[fuel]

When you mean 1G style intake ports - do you mean small like 2G/Evo1-3 or big like VR-4?

 

[donniekak]

Sounds like a 1g 7bolt head.

 

[CBBOOST]

I agree,1G 7-bolt head.
They are pretty much the same as a 6-bolt head appearance wise with the exception of the larger exhaust manifold end studs.