Head inlet bolt angle.

Essex AutoBarn · Post by **Essex AutoBarn** » Fri Dec 04, 2015 11:55 pm

I'm making a custom inlet, and noticed the inlet bolts to the head are not a straight 90 degree, they seem to be an extra 15 degree. anyone know if they is the correct value.

kiwicar · Post by **kiwicar** » Sun Dec 06, 2015 6:16 pm

Hi
what engine, Ford? holden? Lexus? Jag? Buick? chevy LS? early SBC or later Vortec engine?

please some clues
best regards
Mike

SimpleSimon · Post by **SimpleSimon** » Sun Dec 06, 2015 8:46 pm

My guess RV8

Essex AutoBarn · Post by **Essex AutoBarn** » Mon Dec 07, 2015 12:07 pm

Yes sorry Rover V8
I done some better meaurments with a digital gauge and a 3/8 tap in the hole, and it shows 14.9 so I guess 15 is right, as can't see it being 14.9

sidecar · Post by **sidecar** » Mon Dec 07, 2015 1:12 pm

I wondered why they did this with the manifold bolts but then realised that they are actually being very clever! If the bolts went in at 90 degrees then when you torque up the inlet bolts on one cylinder head it could pull the manifold away from the other head, if the second set of bolts are torqued up on the other head something bad would happen!. With the bolts being angled the manifold will self adjust, basically it will slide down into the valley area of the engine until both mating surfaces of the manifold are in contact with their respective cylinder head!