Im about to start building my windsor for propane and low end power for off road. I am going to leave the bottom alone and build up the top end (cam, intake, heads). I know I need high compression for the propane to run correctly. One idea that was thrown my way was to make a budget 393 using a 393 stroker crank, 351 connecting rods and stock 302 pistons which would bump up the compression to 11:1 and give me stroker performance. I have been told that stroker kits can cause serious over heating issues though so I was going to stay away from them, but not terribly sure. Anyway, let me know what components are good and what to stay away from! remember high compression but low end power.

 

Been a long time since I've seen you on the boards!

The overheating is from boring the cylinder too much (typically over .040 on these). Say it's bored to .060...it needs to be sonic checked as the cylinder wall thickness gets too thin and can cause overheating.

My 393 is bored only .030 over and doesn't have any overheating problems, stock radiator so far. I bet it would overheat when pushed though, so far i've just been driving it, some towing...

The 393s are becoming very popular, 408s are too. My engine has a 3.85 crank and stock 302 pistons (Probe forged aluminum). I duno what the rod length is on it, i forget, but it could be stock 351 length.

 

yea, im more on pirate.

I dont really plan on boring it out, whether the machine shop says it needs it due to scoring or whatever is a different story though. So far I might end up doing it, but still looking for some ideas on the other three parts. If I end up going with the budget stroker im not sure if I will get heads or not, but I would like some that flow better.

 

I can help with a couple things...someone else will have to assist, but...

If the engine is in good shape, it might not need to be bored, but it should atleast be honed to re-establish the cylinder walls for the new rings.

You should try to get better heads. Those E7's choke out a 351 around 4500 rpm, a 393 would be around 4000 rpm or so. You'd have an RV or boat engine ha. Not much horsepower available in that setup.

The compression you get out of it totally depends on the piston, head gasket, deck height, and head volume. Selection of these parts puts together your final CR. My 393 has 9.45:1 compression, I have 15cc pistons and 64cc heads.

http://www.turbofast.com.au/Tfcomp.html - compression ratio calculator.

Make sure you use the right headgasket to keep the quench area below .050. Don't use too thin or too thick of a gasket to change the CR. Gasket should be .040 or so, depending on your block.

 

hmm.... ok, so even with that stroker setup i can still run a nicer set of heads without the compression going through the roof. i think i might just do it. (this is getting expensive ) i think im going to run an Edelbrock Performer intake, so now i just need to figure what cam and heads to run.

 

We all know that the AFR 185 would really set that 393 build off if you can spring it. the cam would be determined once you figure out what heads your gonna run. CompCam or CamMotion (custom grind) would be the guys to call with the specs on the motor and what its being used for. aluminum heads also allow you to run a bit higher compression before you get detonation unlike Cast heads. but if you plan to run on 87octane fuel at any point keep the cr below 9.6 with aluminum and 9.5 with cast.

 

AFR185?

no pump gas, running propane. 110 octane

 

AFR 185's are aftermarket aluminum cylinder heads made by air flow research. 2.02 intakes/1.6x exhaust valves. cheers, garsten

 

gotchya. One thing I have been told is that aluminum heads crack or get damaged very easily.

whew $1,329.99 for a pair through Jegs!

 

AFR makes excellent heads, I'm going to run 185s on my 393 someday.

Most if not all aftermarket aluminum heads are 1100-1400ish...the AFRs are about the same price as others but perform very well.

My 393 with AFR185s and a trick flow intake with the right cam could easily make 470-480hp on pump gas, bout 500tq.

Aluminum heads are perfectly fine to use provided running them on propane is acceptable, I don't have any experience with running one on propane but I assume fuel is fuel and you wouldn't have any problems...

Most of the heads out there are aluminum, if that puts ur mind at ease. You've got to use a bi-metal headgasket though, since it's a cast block and aluminum head (expand at different rates). My 393 has aluminum heads, they shave about 50 lbs off the front end too (much lighter than cast).

There are a boatload of heads to choose from, look around and you can even use this flow data chart to help you...

http://home.isoa.net/~mharrisj/fordhead.html

I was on a budget when I did my 393, and chose the ford GT-40Y heads. They're pretty much inbetween say that AFR185 and the stock E7 heads. They're still a little small for my engine, I won't get more than 320-330 rwhp from them I'd say. But ya can't beat them for $600-$700 new. Someday I'll do a little revamping and get this motor crankin'

 

ok, so whats the downside to cast heads besides the weight?

thanks for the chart BTW

 

The aluminum heads will allow someone to run a higher compression ratio before detonation, usually about a point. So a disadvantage to cast heads is the opposite...