I have just completed the break down on a sb 355 and just before I started to order parts a friend of mine gave me a 400 sb . The 400 dose not have any thing in it and it needs to be bored ( just to clean it up ) . What would you do ,use the motor you have parts for or, start fresh on a 400 . I will have to use the stock 76 cc heads I had on the 350 for now . Any comments ?

 

I'd probably build the one I already had parts for. You can accumulate parts to build the 400 over time.

 

If theres an up-time that you have to meet, then I agree with the above. Build the 400 up right.

 

I dont have a time spand to keep up with . I can build either of them in the same amont of time and the caust will be pretty close to the same if i can use my old heads . I was just wondering if the 400 is that much better or not .

 

Don't wreck a 400 with smogger-crap 76cc heads. The factory did and it was a total shame and then some.

I can attest to a 400 being better than a 350 (all else being equal). Either way, though, the heads are crap on either engine.

 

bigger motor is always better, maybe you could have the block mag'd and tanked first to see if it's a rebuildable core, then sell off the 350 pieces to buy stuff for your 406 then.

 

your're going to need a lot of "special" parts for the 400 and it would cost a little more to build. if time is an issue, i say go with the 355 and build the 400 as you go. my .02 cents. good luck

 

Thank you all for your input . I think that i am going to use the 400 and maybe even my crap heads . I think that they are ok , they are accualy 1969 heads w / better valves and springs in them ( I am porting them my self ) . I will look into it alittle more before I start ordering parts . Thanks again.