GN1 Heads- 8 bolt versus 14 bolt --Help

[mzunino]

I bought a set of heads off a board member a few months back. I checked them out when they came and they looked perfect, took them to my guy today to have some port work done and realized they are 14 bolt. I specifically asked before I bought them if they were 8 and told yes. The question is can you run the 14 bolt on a 109 with no head gasket issues? I am beside myself for not noticing when I got them but I put them on the shelf and there they stayed till now. I am really looking for some help here because I am not sure what to do next.

 

[TurboDave]

Yes, they'll work. You just use the standard 8 bolt locations, and any good high quality 8 bolt head gasket.

 

[mzunino]

Thanks for the reply Dave. So basically no difference in terms of contact surface and gasket seal?

 

[earcher1]

Thanks for the reply Dave. So basically no difference in terms of contact surface and gasket seal?

correct... i have 14 bolt heads on my engine and i just drove my car most of the day.

 

[mzunino]

Thanks alot guys. I figured the block deck might be different for the Stage motors and these might not match up.

 

[101prf]

I've had 14 bolt heads on my 109 block for years with no headgasket issues. When I bought mine the roller rockers cost less for the 14 bolt heads.

 

[TurboBuRick]

Thanks alot guys. I figured the block deck might be different for the Stage motors and these might not match up.

Many here are running 14 bolt heads on 8 bolt blocks. Including myself.

 

[bison]

To be totally honest idk why most would even run the 8 bolt style. You can't even get a decent rocker setup on them. Tye only advantage i see is they are pretty much out of the box bolt ons with new gaskets and fasteners. The fastest of the fast run 14 bolt heads. If I were to do it again I'd have ordered with the longer chevy valves to open up spring selection.

 

[BEATAV8]

14 bolts heads with Scorpion rockers and ARP rocker studs is the way to go.

The 8 bolt style are just a waste of time.

 

[Boostdeznuts]

Hey Mark you never ask me about the bolt, I'll take them back if you are not happy

Thx
Lenny

 

[GNTIM]

I ordered 14 bolt heads just in case I step up to a better block, plus I figured if I sold them, it would be a plus.

 

[thunderace31]

So 14 bolt heads are Stage motor heads then? Sorry to ask in a thread but this head issue/Difference thing has boggled me for some time.

 

[2QUICK2B6]

T&D 's are higher for 14 bolt heads

 

[Pittsburghkid]

So 14 bolt heads are Stage motor heads then? Sorry to ask in a thread but this head issue/Difference thing has boggled me for some time.

Stage heads are 14 bolt heads but just because some heads may have 14 bolt locations doesn't make them stage heads. Some aftermarket 231 blocks utilize 14 bolts because of the better sealing capabilites so there for they make 14 bolt heads that will work with the 109 blocks but not stage blocks.

Here's an example.

Aluminum Engine Blocks, 231 Turbo V6 Buick Aluminum Cylinder Block, TA_V3800 | TAPerformance.com

 

[bison]

The heads are all from the same casting. An 8 bolt set could be converted to 14 bolt style in a milling machine with minimal fixturing. Being able to run the stronger rocker setup is more important than having the 6 extra holes which probably will never be used on a production block. Milling to the correct height then drilling and tapping/bottom tapping the holes are what's needed to get it done. Of couse you will need a set of t&d or scorpion rockers to bolt up. If you had a geometry issue you could nail it almost perfectly when milling the heads for the rocker stands. I typically use about .090 thick shims with the t&d setup. If I were to mill a set of pedestals off I'd leave them .090 taller and probably not need any shims in most instances. Measure twice and cut once