[luggnut73]

I am seriously thinking of buying a '81 engine for my 240. I want to run my SUs but the manifold I have have square ports and if Iam not mistaken the 81 has round ports . My question is , is there a intake manifold for these 4 bolt SUs that will work . Also can I use the 280 stock exhost or should I just go headers. If I do this it will happen by this week end so if you have the info please respond or tell me where to find it. I tried the surch and articles no luck . Thanks Gary Portland

 

[gbvol54]

I think your easiest path would be to use the head and manifolds from your 240 on the 280 block. Assuming the '81 is a non turbo it should have flat top pistons which, with your 240 head, will give you around 10-1 compression ratio. May need to adjust timing to avoid pings but should bolt right up.

 

[K Simmons]

I think you are confused. If you aren't then I am!

I have always thought that when people talked about square or round ports, that only the exhaust ports were square and all intake ports were round. I know they are round on both my E88 and N42 while the exhaust ports on the N42 are square(I don't know about the exhaust ports on the E88).