5.09 rods ?



I'm new to the forum and new to ford small sixes. My son just got a 65
fastback progect with a 200 and a 3 speed. He wants a V8 so I'm going to take the six and try to build it a little bit for a 65 or 66 coupe I'm looking for. The thing that strikes me about these engines besides their lightweight block yet strong bottom end is the terrible rod ratio. Has anyone tried SBF 5.09" rods. In a 200 this would give you a ratio of 1.63 thats a bit better. Or how about a 170 crank in a 200 block. That is a very decent 1.73 and you would still have 190 cubes or more. There are off the shelf pistons available with 1.26 comp. Ht. Sound possible or has this all been gone over before.
I thought the 170 was 7-main after 66. The journals are the same size but I don't know about side clearance. But increasing the stroke? May be on the 250 one could offset grind the rod journals to SBC small journal size and run the 6.2 rods with 305 pistons (3.736 bore) and have a 266 or so. Still have a pretty bad ratio but I'm not sure that would hurt on a low rpm torquer.
BTW its nice to find a forum where the people are knowledgeable and courteous. Thanks, Franklin
8) one thing you always have to check for is the size of the big end of the rod, and not just the journal opening. often times the V8 rods have larger big ends even though they fit the same journal, and this could cause cam clearence problems. as for being courtious, if we are not jack hunts us down and beats us with a rubber hose ;) ;) :LOL: :LOL: :LOL: :LOL:
At the risk of repeating myself, forget the 200ci six, go with the 250, even with stacks less rpm, it will be quicker. The Aussie crossflow is the way to go here.
If you want to improve the rod ratio the aussie 200 six had 6.27 rods, and we have a piston available off the shelf to fit these rods into a 250, giving rod ratio of 6.27/3.91=1.60. This is apparantly the hot setup with racing 250 crossflows. BTW later OHC engines have 6 inch rods with same block height. But with 3.64 bore.
I think the 188 crank might be the way for me to go. I want to build a high rpm short stroke motor. Obviously the limiting factor is the log head. But with limited funds I'm lookin at off the shelf and junk-yard parts.
The 2.2 chevy heads look like a possibility. They look like they would bolt right on with a little reaming of the bolt holes. They are aluminium cross-flow canted valve design with typical chevy valve train and the junk-yards are full of them. (there may be a reason for that) Of course I'll have to chop two ends off and get them welded together. I suppose that can be done, I know next to nothing about welding aluminium. Then there is the problem of chevy heads on a Ford. I guess I could put a ford decal on them and say the're from OZ. ;)
8) the nice thing about running longer rods is the heads become less of a limiting factor, though not much less.
A hybrid head may pose other problems. For example, if you change the port layout, you'll have to alter the cam to match. that may be tough to do unless it is the same port order as a crossflow.
After a number of years, I'm just getting back into cars. Where do I go to look for an off-the-shelf piston with a 1.26" pin height? I'd like to increase the rod ratio in my 2.3L HSC. Thanks in advance.
Keith Black lists two pistons for a 305 chevy with a 1.26 comp. ht. One is a flat top. the other a small dome. Don't know if these would work with the hsc. There's also 1.43 (can't remember if its dish or not) All these have the chevy pin (.927) size. The 2.3 HSC has 5.45" rod with a ratio of 1.65 in stock form. That's better than our small sixes. BTW does anyone know the width of the big end of the rod on the 200/250.