I know Ross Machine Racing makes injector bungs. But I'm not real sure on the specifics. (if they fit our injector etc.)
I was thinking something along the lines of threading the outside of the injector bung with a die, drilling out the heads injector hole large enough for the outside of the bung, and then taping the heads.
You could swap the plug out for the bung whenever you decide you want to.

I'm also not sure if you'll run into any dissimilar metal problems since the bungs are aluminum.. I'm sure there is a sealant or something for that though.

Andy, I get what you're doing. The word "modular" comes to mind.

I think you should be able to do it without too much trouble. If you're worried about turbulence, it will probably be negligible. You just need to figure out a way to easily switch from one configuration to another. "Expanded" rubber stoppers aren't a bad idea, but it would be nice to see you using something like what Mike posted. A threaded bung sounds much more reliable, with a more consistent seal.

What about using a dual fuel rail setup with 2 sets of injectors? Use a L67 fuel rail and injectors to provide gasoline and use the L36 fuel rail and injectors for methanol?

I think I might need to make it more clear what this is all about...

Think classic full top swap (L67 heads, LIM, M90, etc.) or "cheapy" version of the zzp ss M90 kit (using L67 heads, LIM, M90 and fuel rail instead of their modded pieces and billet fuel logs), but with the ability to temporarily switch back to L36 UIM/LIM/fuel rail for visual inspections (necessitating some means of surreptitiously plugging the L67 head injector holes).

Wouldn't 6 core (welch?) plugs knocked into the injector ports work? No machining required, very cheap, readily reversible and would look permanent enough to pass even if picked up on. The size may be difficult to match but core plugs are around in a pretty big variety of sizes. Maybe look at those used to block other than cooling system holes (head and block) eg. in TB'* and manifolds.

Reading through again, I'm on board with using the L67 head ports, not closing them off and sending out an L36 intake to have it plugged and machined so that you can't see the old injector holes.

That leaves one question that I could answer tonight. Is the L36 rail taller than the L67?

OK, I see where you're going with this...could the stock L67 fuel rail plug into L67 heads and still fit over top the L36 UIM?

Awaiting results

well i think so the blower look as high and wider than the l36 upper


L36 upper is 6 inches high and 7 1/2 wide

I'm betting the blower is wider, but alot shorter, than the L36 UIM. I hope I'm wrong about the height

with the ability to switch back... Why would you want to and what are you going to do, ask your M90 to remove itself and hide in the trunk? If you can make a M90 Look like a L36 upper then your all set, I think I am hoplessly lost you can shoot me now