OK, I have been lurking here fo a while reading everything, and I never got to see the specs for the exact engine I want, so I made a new post.

This engine will go in a F350 dually. It is going to be converted to 4wd and have the bed made into a dump bed. This will be used mostly for things loaded with a forklift, that can damage my bed. I also have a diesel, and drive it primarily, but I am tired of tearing it up on this stuff.

I'll load firewood, and goofy things at work that don't fit in my bed, and take my mower around in it for mowing. It may see 5k miles per year.

I am not interested in HP at all. My diesel has 195, in throry. I'd like a torquey engine, right off idle, that can get decent mileage, like 14 or 15 driving 55 mph. If this engine can't do it - I'll get another one. I'd even put a 300-6 in this thing. I really don't care.

This engine has about 2k miles on it. It's a Recon rebuild, and I was never happy with it. I know nothing about it except that I put it in.

Here's the plan:

I will pull the engine and tear it back apart. I would like to leave the pistons and crank in there if at all possible. I was looking at a few cams, but am leaning towards the 255deh. I'll get the K kit with it. I'd lik to check the compression and get it as close to the low side of 9 as possible. I intend to do this through milling the head. I don't know what the current CR is, but I'll figure it out.

I have an edelbrock 1406 carb and intake on it. I also have the factory intake and carb. The carb i bought has mechanical secondaries, on it, and I am considering selling it and getting one with vacuum secendaries.

The distributor is a replacemnt one, and I would like to figure out a good curve for this thing and have it curved. I am not opposed to aftermarket ignitions, but don't know what is best. I do not have an EGR on this thing. I have been hving a hard time setting the timing on this - it won't knock even if the timing is 15 degrees too advanced. I set it at 8 btdc currently, but my mileage is terrible - 6-7 mpg.

I am getting a zf5 tansmission for this, and will run as close to the 3.73 gears currently in it. I like those gears, wish they were in my diesel.

So my questions are:
1) Is this the best camshaft?
2) Is this the best CR to shoot for and the best way to get it?
3) What's the best thing to do regarding the carb?
4) Does anyone have access to a good timing curve for this?
5) Will the EGR not being there hurt me or help me?
6) What would you guys do different on this?

 

First of all you may have a tough time getting 15 mpg out of a dually. That said I would call Comp or Crane and tell them what you want and see if they recommend a different or custom grind. Off the shelf I would think that the 255deh would be the best. Depending what you ordered for a crate engine you may have one with the cam retarded 4 degrees. When you pull the timeing cover check that out. If it is only a single groove one get a different timing set that you can set straight up at 0. Before you talk to the cam techs I would figure out what you will have cr wise. use this link to play with the numbers to see how you can arrive at it. With the smaller cam you won't be able to run too high of a cr without pinging. For pump gas you want to stay aroung 8.8:1 dynamic cr. The carb you have may work if you can get it to let you know when you hit the secondaries. Linkage may be able to be played with a little to make that more noticeable, otherwise the vacuum is the way to go. I think you will have to leave the curve go until you know the cam and cr you are working with. Hope this helps. Others will chime in I'm sure.

 

what do you think about milling the head to modify CR?

 

You would have to take off a significant amount to make any difference and then you get into valvetrain geometry and having to do the block an equal amount so that they mate properly. The flat top pistons are probably the best way to go for the money. I forgot the link to the dr calculator in the last post. It's here.http://kb-silvolite.com/calc.php?PHP...8a4c4f13feafcd

 

if you want to keep pistons and if they are not flattop I'd really consider the aussie heads- iron- will cost about $400 plus build. Compression is huge obviously and you need to get it at about 9:1 which the flattop piston do ($160 or so). Then with the 255deh cam your right in the ballpark for the right dynamic compression for 87 pump gas. You can use the 2v carb and intake and make a 'stock' '1971 400 that has about 400ftlbs down low.

The aussie heads give you the compression by smaller combustion chamber so you can use the stock pistons- those heads also breathe differently and will help low end and hurt hp a bit. Theres also a couple less known intakes that are supposed to really kick in the low end.

I was looking into shaving the heads and block but it has to be taken apart and costs more than making more reasonable torque using parts listed.