"Stoppered" L67 heads on an L36?
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Anyone think it would be possible to put L67 heads on an L36, but with the injector holes "stoppered" somehow?
(I'm thinking something like a small, gasoline-proof rubber or polyurethane stopper with a tapered screw running through the middle to make it "bulge" and hold fast in the injector hole)
What do you think...doable? Any better ideas for how this might be accomplished?
(I'm thinking something like a small, gasoline-proof rubber or polyurethane stopper with a tapered screw running through the middle to make it "bulge" and hold fast in the injector hole)
What do you think...doable? Any better ideas for how this might be accomplished?
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Originally Posted by BillBoost37
Flow might be a bit turbulant from the port and stopper.
I see what your planning thought.
I see what your planning thought.
I would not care much about flow while in "L36 mode"...it'* more a question of "if I ran like that for a few weeks, would I blow up the engine?"
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Originally Posted by BillBoost37
I doubt it would blow. If the stopers didn't come out or get pulled in.
What is your plan for the LIM?
What is your plan for the LIM?
If I fabbed it up right, I might even be able to develop a "cover" that not only hides the stoppered holes, but prevents the stoppers backing out...hmmm
Now I'm maybe thinking wooden (or metal) dowels worked to accept injector o-rings, and held in place with some aluminum angle...or some pour-in-place RTV that will fill the entire machined out area as well as the injector hole...
I would plan to run stoppered L67 heads, L36 UIM / LIM / fuel rail / injectors (and maybe valve covers) in "L36 mode", and unstoppered L67 heads, L67 */C / LIM / fuel rail / injectors / valve covers in "L67 mode."
It'* more work, but maybe..
Drill the injector holes out large enough to put a externally threaded injector bung in there..
That way you could just drill and tap them..
Or.. even better.. just drill and tap the L36 LIM (and port out the injector hump) and run the injectors in the head, n/a.
You would have to modify the L67 rails to work or get a set of reworked stockers from a vendor though.
Just putting that out there.. I would be weary of a formable plug there.. But thats just because I'm not real familiar with it.
If you want info on what tap and plug to get, I have the info somewhere from when I did my buddies F-body L36 LIM.
Drill the injector holes out large enough to put a externally threaded injector bung in there..
That way you could just drill and tap them..
Or.. even better.. just drill and tap the L36 LIM (and port out the injector hump) and run the injectors in the head, n/a.
You would have to modify the L67 rails to work or get a set of reworked stockers from a vendor though.
Just putting that out there.. I would be weary of a formable plug there.. But thats just because I'm not real familiar with it.
If you want info on what tap and plug to get, I have the info somewhere from when I did my buddies F-body L36 LIM.
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Originally Posted by 95naSTA
It'* more work, but maybe..
Drill the injector holes out large enough to put a externally threaded injector bung in there..
That way you could just drill and tap them..
Or.. even better.. just drill and tap the L36 LIM (and port out the injector hump) and run the injectors in the head, n/a.
You would have to modify the L67 rails to work or get a set of reworked stockers from a vendor though.
Just putting that out there.. I would be weary of a formable plug there.. But thats just because I'm not real familiar with it.
If you want info on what tap and plug to get, I have the info somewhere from when I did my buddies F-body L36 LIM.
Drill the injector holes out large enough to put a externally threaded injector bung in there..
That way you could just drill and tap them..
Or.. even better.. just drill and tap the L36 LIM (and port out the injector hump) and run the injectors in the head, n/a.
You would have to modify the L67 rails to work or get a set of reworked stockers from a vendor though.
Just putting that out there.. I would be weary of a formable plug there.. But thats just because I'm not real familiar with it.
If you want info on what tap and plug to get, I have the info somewhere from when I did my buddies F-body L36 LIM.
1) Part of what I'm trying to avoid is:
a) paying big $$$ for a vendor-supplied solution, or
b) modding my own fuel rails, which I see as potentially leading to death and/or disfigurement
2) Also, when running n/a, it would have to LOOK just like a stock L36, so no modded or aftermarket fuel rails allowed when in n/a mode.
Drilling-and-tapping is an intriguing idea...I wonder if that could be done to the L67 heads such that either a threaded plug or an injector-with-o ring would fit.
You mentioned "injector bung"...is there a ready-made aftermarket piece you know of? (Kinda like an O2 bung plug?)
FWIW there is a local guy here with an SS M90 kit. Well.....he blew up the L36 and put a stock L67 longblock in it, but wanted to keep his SS kit LIM and fuel rails.... So he left the L67 heads on the engine and drilled and tapped them and put bolts in them with some thread sealer. Has worked well for him so far.
[quote="agrazela"]Anyone think it would be possible to put L67 heads on an L36, but with the injector holes "stoppered" somehow?/quote]
Yes, and I doubt it will make any difference in airflow. When I did my L36 to L67 Series II, I noticed that the head castings are the same, they all have the bumps in the castings where the injector bosses are milled on just the L67 heads.
As for plugs...I would tap them for the nearest size of pipe plug and go with that.
However, You might be better off using L67 fuel rails and putting the injectors in the head holes, and plug the manifold bosses, or just have the manifold casting welded closed.
Yes, and I doubt it will make any difference in airflow. When I did my L36 to L67 Series II, I noticed that the head castings are the same, they all have the bumps in the castings where the injector bosses are milled on just the L67 heads.
As for plugs...I would tap them for the nearest size of pipe plug and go with that.
However, You might be better off using L67 fuel rails and putting the injectors in the head holes, and plug the manifold bosses, or just have the manifold casting welded closed.





