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ive heard that you can convert a single port head to a duel port
has anyone seen this done?
i heard that the plans were online but i cant seem to find them anywhere, googles let us down

anyone HELP??
or am i going to have to revive the lost art?

p.s the reason im doing this and not just getting duel ports is that i reacon i can flow them much better and the fact they will be cheaper

What are your plans?

Do you mean putting MPFI dual inlet heads on your carby engine and putting a carby on top of the MPFI intake plenum?

You will probably gain at most about 5hp, maybe more with porting and cams.

If you have single port heads, you cannot turn these into dual port heads. A dual port conversion is taking a carbie engine block and putting the MPFI dual port heads on the carbie block...

That'll be the only way you'll get dual port heads, unless your a pro in metalurgy (spelling???)...

Cheers

Bennie

don't tell that to the guys that used to divide the shared ports on oldhen straight sixes.They used to use a heavy duty epoxy resin. I used this resin to seal the water chamber of a manifold after two welding jobs caused a few leaks. Stuck a four barrel Holley where a 2 barrel stromberg sat

El_Freddo wrote:That'll be the only way you'll get dual port heads, unless your a pro in metalurgy (spelling???)...

Quote Ulysses Everett McGill: "Say, any of you boys smithies? Or, if not smithies per se, were you otherwise trained in the metallurgic arts before straitened circumstances forced you into a life of aimless wanderin'?"

HAHAHA O' BROTHER WHERE ART THOU..... I love that movie....

brumbybear wrote:HAHAHA O' BROTHER WHERE ART THOU..... I love that movie....

The best movie ever I can watch it over and over again and still never get sick of it

WTF!! whatmovie??

well the plan is to take the single port heads i have here, put them on the mill open the mouth to within 1.5 mil of the water jacket epoxy or tig weld a sliver of ally in between the throats and then clean it up, will then have a custom efi sitting with it

spike wrote:WTF!! whatmovie??

brumbybear wrote:O' BROTHER WHERE ART THOU

well the plan is to take the single port heads i have here, put them on the mill open the mouth to within 1.5 mil of the water jacket epoxy or tig weld a sliver of ally in between the throats and then clean it up, will then have a custom efi sitting with it

Why?? Wouldn't it be a lot easier (and cheaper) to use EFI heads?

romeo and juiliet??
probably easier.
not cheaper considering ive got the heads sitting there
and its cause i reacon i can get more flow

spike wrote:romeo and juiliet??
probably easier.
not cheaper considering ive got the heads sitting there
and its cause i reacon i can get more flow

What does Romeo and Juliet have to do with it??

Anyway.. The ports on the EFI heads are much larger and can be opened more (like the Carby model heads). Have you seen any EFI heads? I have some EFI heads if you need some?

This is just my opinion from experiance.

mettalurgy??
i aint got no idea hahah
ive seen them but i still think i can open the carby ones more than the efi ones

spike wrote:ive seen them but i still think i can open the carby ones more than the efi ones

I doubt that highly. Combined the EFI ports have more area than the carbie ports does.

I would like to see you do it to see what the results are, but I'd still put my money on the EFI ports being the go.

Steptoe - The old holden sixes have very large ports when shared between two cylinders. If the port is divided you can use the later model or aftermarket manifolds to make the flow more efficient. The reason for the epoxy is typically due to race regulations and head restrictions - as in they have to use the original heads that came with those motors meaning shared inlet ports...

Cheers

Bennie

we worked out that it only needs a 25mm diameter port and i can get almost 30mm out of it

when you look at most porting the first thing you do is take the small lump off the inside of the port, this is put there to split the flow, first thing you should do is maake it smaller almost to a knife edge

didn't that member from up north that had his fully worked get billet ones made from scratch? I would love to see those babies!!!