Intake manifolds

Ken Blythen · Post by **Ken Blythen** » Tue Oct 10, 2006 9:46 am

I've seen several 270's (I know one of these was a '45 ) with different inlet manifolds fitted. They had a distinctly flatter section in the tube portion between the carb. & the head.
Did these manifolds perform better or just come from a different supplier?

Ken B

RANGER · Post by **RANGER** » Tue Oct 10, 2006 12:58 pm

You may have seen an intake from the military 302 They are flat. The WWII 270 only accepts intake manifolds with thesmaller size pilot rings. Part Numbers will have to match those in the SNLs, be for a 1bbl carburetor and will have the horn mounting bracket cast into it. It will also have to have the correct thread size in the center for the fittings for the vacuum check valve.

Ken Blythen · Post by **Ken Blythen** » Wed Oct 11, 2006 5:24 pm

I don't know if any 302's came to NZ but these engines are certainly 270's (per eng. no. at distributor).Maybe the later 270 had the same style of manifold casting. Horn lug, hydrovac hole etc all there.
Just curious -Thanks

Ken B

RANGER · Post by **RANGER** » Wed Oct 11, 2006 8:42 pm

It gets into a can of worm with the later 270s of the 50s, as the heads and intake manifods and heads may not interchange with WWIIbecause of inlet porting dimensions and piston configurations. there are some collectors who get into this but they end up with Heinz 57 variety trucks which become nightmares for future owners. If you could get the casting numbers from the intake it may ID them. I do not have books for the later 50s civilian 270s, but I have a contact or two.

Guest · Post by **Guest** » Thu Oct 12, 2006 9:44 am

Thanks Ranger

It's probably not worth going to major effort at this stage. I mainly wondered if performance or economy were significantly improved, making it worth getting one of these manifolds at some point.

Ken

RANGER · Post by **RANGER** » Thu Oct 12, 2006 12:59 pm

There is nothing much that will add economy to a WWII CCKW geared for use in combat, but there are modified heads manifolds with dual carburetors and adaptations of the 71 series Diesel blowers that will let your 270 deliver 250+ Hoesepower to the rear axles. Before the modern V-8 blossemed in the mid 50s, the GMC 270 was a popular speedster engine and had the potential for these mods.It is still done and one of these GMC engines in an early 50s GM pickup recently set a speed record approaching 200MPH at the Bonneville Salt Flats. I supplied some of the parts for the engine. In 1953-54, GMC offered an engine to be used in the Chevrolet Police cars. They were tough, I do not have the information at hand though.