Hi guys. New here but been on slick60's for a bit. I have a 1965 f100 swb 2 wheel drive. Has original 240 with 3.03 trans and 3.73 rear gear. I plan on keeping the 3.03 and run it behind a 1968 302 I have. Quick run down on the motor.. stock bottom '68 302, 1997 gt40p heads with stock 1.85 1.46 valves, bowls blended and exhaust ported. Gasket matched on the intake side. 600 cfm carb and GTp headers. Like I stated I want to run the 3 speed with a better clutch from Jeg's and keep the 3.73 gears. Truck weighs 3800 full of fuel not including my 230 lbs. So a shade over 4000 with me in it. Tires are 235/70 so normal street tire size. I'm looking for a streetable cam that will be reliable and have some hotrod power to it. I'm looking for hydro flat tappet because cost is a major concern. Looking for more low and midrange power than top end necessarily. I have called every cam manufacturer I can think of and give them all the same specs. Some say I need duel pattern and some single, some say around 260 duration and some say 270, lift is from 440 to 500 + depending on what company I talk to. The most middle of the road so far is a Howard's at 269/269 215/215 .475 .475 110lc. I also found an Elgin that is 272/272 216/216 .484 .484 110lc This is my first Ford build so I have no idea. Any help would be very appreciated. Thanks, Joe

 

I wouldn't go with a more that 260ish total duration in a 302 truck engine because even with that the meat of the powerband will be towards higher rpms. When you get into 270+ you start to get more of a 3000-6000rpm powerband unless the vehicle is really light(under 3k lbs). As for valve lift get as much as you can but be aware anything over 0.500" will require upgraded valve springs and retainers as the stockers will bind, and even below that lift a stiffer spring isn't a bad idea.. the stockers are barely strong enough to prevent valve float at 5000rpm.

 

Thanks for the help. Yes, I was already planning on new springs along with the cam and lifters. I will look for something in the 260 duration range then. Thanks again

 

Would a cam with the following specs be a decsent street cam for a truck with a 302? 259/267 205/215@ 50 .448 .480 112 lsa with 108 intake centerline. I also forgot to mention in my first post that the heads will be milled for 10-1 compression.

 

Yes that would be a decent cam, don't go too crazy with compression or detonation will be a problem.. exasperated by the heavier vehicle again.

 

Ok thanks. I will keep that in mind. I really appreciate the help

 

Would duel pattern or single be better? I found this cam 265/265 210/210@50 .469/ .469 would this cam or the previous dual pattern be better? I also found one 272/272 216/216@50 .484/ .484. I know it's more advertised duration but being single pattern may help. Also I know gt40p heads flow better than stock but not sure we'll enough to go single. Sorry for all the questions but trying to learn.

 

Exhaust ports always flow less than intake ports and dual pattern cams compensate for this somewhat, so no a single pattern cam isn't better. GT40p heads flow 30% better than E7 heads which is theoretically enough for over 350hp.

 

Thank you for all of your help. I went with the 205/215@50 .448/.480. I really appreciate all of the advice. Its a Howard's cam and lifter set so hopefully it will be ok quality. I'm not looking for too much, 280 -300 hp and 320 lb/ft would make me really happy. Anything over that is gravy.

 

I think with around 9.5:1 compression you will meet or exceed your goals, also the motor should make 350 TQ with some kind of header on it.

 

That's awesome to hear. I should be at 9.5 to 9.8 with the gt40p's with no milling. Going from the old 240 L6 to a 302 with300 hp/ 350 lb/ft would be great.

 

Ok new question on this motor. I got into it and thought I was going to be able to use the short block but was sad to find it was ran without oil at some point. All the bearings were shot, crank had to be turned, rod ends shot and piston skirts were scored. I was able to hone the block by some miracle and that turned out ok. Crank turned 10/10 and got new rods from ford racing. Heads had to be milled 6 thousandths so no big change in combustion chamber cc. My question deals in piston selection. It looks like most pistons are 1.605 or 1.585 compression distance with -8 head volume. I did find some summit brand ones that are 1.605 with +3 head volume. Should I go with those or the lower compression ones? also, the guy helping me thinks we should leave the second compression ring off. Swears he has done it on every motor he has built for the past 30+ years. I'm not sure what do you guys think?

 

I'd go with the slightly dished heads and I'd politely ignore the friend(umm.. chevy guy?) and install all the piston rings.

 

Yes, he is a Chevy guy. Ok. I will use all three rings. The -8 Pistons show a compression ratio of 8.9-1 on a 58 cc head and 8.206 deck height. Isn't that a bit low? Thank you for your help

 

Are those pistons flat tops with valve eyebrows or true flat tops with a slight dish? Make sure you get something with eyebrows just to ensure valve clearance now and in the future should you change the heads or the cam.
You have milled parts there now too(was the block's deck milled?) so make sure you are using the correct numbers. I calculate 9.28 static CR with the -8cc dished pistons and a 60cc head which is pretty good IMO, you might want to measure a chamber or two now to be sure. With the +3cc pistons that jumps to 10.7:1 CR which is too much for a heavy vehicle. Also note the actual compressed thickness of the head gasket you have... ie: get real numbers for everything don't make any assumptions.