can anybody tell what my compression ratio on my truck is???
more or less?
86 Ford 4x4 5.0-302
273-40 sealed power pistons
6037 edelbrock heads 60 cc
huh? aint got a clue on deck height or piston cc?
ANY HELP WOULD BE VERY APPRECIATED!!!!!!!!!

 

those pistons, if i remember correctly, have about 3-4 cc of flycutting in them. along with the edelbrocks (actually 60.4 cc)that means youre looking at about 9.6-9.7 to 1 compression with a piston that is reasonably close to zero deck. sometimes though, ford built those engines with the pistons as much as five thousanths proud. id estimate 9.6 and be happy with that.

 

Seems you were right on! I found a web site with a compression ratio calculator and with -4cc on the pistons It came up with 9.8.1
with -3 9.6.1. that was with a zero deck. well MR adam seems you know your stuff, I have
another question. what cam do you recommend for my truck.
I want this truck to accelarate hard&fast. most responces I have gotten are with about a .445 to .462 on the intake and a .470 to .480 on the exaust. 204 to 214 duration@50 with around a 112 to 115 lobe sep. I drive it every day so I want my bottom end torque as well. what do you think.

 

well, i can spec out a cam, just like anyone can, but you need to look at the big picture too. every engine has specific needs, and the off-the-shelf grinds are sort of like staggered stopgaps. there is no such thing as a perfect off-the-shelf camshaft for your engine. you can get close, but not perfect. for about 300 dollars, Terry at CamMotion can supply you with a custom cam, that will make way more power and torque than anything someone on here could chose, or anything those goons at the Comp Cams tech line could suggest. but then again, we are talking about 300 bucks, versus 100.

what i need to know before i could suggest a cam is the following things.

what transmission, what gears, what form of induction (carb or efi), what manifold, and what sort of exhaust youve got, and what type of cam youre running in the first place (roller or flat, hydro or solid).

those heads are excellent for trucks. i would not go with less than .500 lift, no matter what. youll probably be forced to use a 114 degree lobe separation if youve got EFI. you can go lower with a carb, but you dont want to drop below 110 in a truck. i wouldnt even go that low. if youve got an auto, with a stock converter, your max duration should be kept below 220 degrees at .050.

if youve got a roller cam, then you would be well served with the flavor of the month Extreme Energy cams from CompCams. if youve got a flat, i would go with something like the Crower Compu Pro 276 HDP.

its a 212/216 .491/.502 112 cam. id use 1.7 rockers with this (check your clearances). that would provide very nice low end torque, and breath well all the way up to about 5900 rpm. you can get that from P.A.W. as part number 15211.

 

HERE ARE MY SPECS:
TRANNY- AOD-FIOD/W B&M SHIFT KIT
HAS A STALL CONVERTER FROM AN SVO MUSTANG RATED AT 2350
CAN BRAKE HOLD ONLY TO 1900
WILL PLAN LATER WHEN TRANNY DIES TO GO WITH A NON LOCK UP VERSION WITH A 2500 STALL, EXTRA CLUTCH DISCS MODIFIED
VALVE BODY ETC.
3.55 GEARS RATIO-W 32.11.50.15 BFG ALL TERRAIN-PLAN TO HAVE 275-60-15 FOR PART TIME USE. "TO INCREASE GEAR RATIO"
ITS AN EFI SPEED DENSITY W STOCK INTAKE, PLAN TO GET THE ONLY INTAKE AVAILABLE FOR IT, EDELBROCK 3841.
STOCK THROTTLE BODY, DONT IF I WANT TO PAY 300.00 FOR UPGRADE, IS IT WORTH IT?
HAVE DYNOMAX JET HOTS 1.5 PRIMARYS 2.5 COLLECTORS P.N. 86054
HAVE A FLAT HYDRO CAM 194-204@50 .424-.448 115 LOBE SEP.
GOTTA GET THE RIGHT CAM SO CAN FINALLY GET THE DIABLO CHIP TO PUT ALL TOGETHER!
BY THE WAY YOU ARE THE FIRST PERSON TO TELL ME TO USE A 5INCH LIFT, THESE HEADS FLOW A MAX OF 226 CFM AT THIS LIFT
SO IT MAKES SENSE TO ME WHAT YOU SAY. THAT CAM YOU MENTIONED WITH A .491/.502 IS THAT WITH A 1.6 OR 1.7 RATIO
IF ITS 1.6 AND I USE 1.7 WHAT WOULD THE RATIO BE?
HEY ONCE AGAIN I LIKE WHAT I HERE SEEMS YOU KNOW WHATS GOING ON WITH DA PERFORMANCE END OF THINGS
GIMME SOMO INFO

 

if youre going to go with a higher stall converter, then you can add a little bit more duration. i, however, would probably keep it where it is. you dont want to lose any torque. the converter is an excellent idea though. i suggest you do it when you drop the engine in.

yes, the lift is more than most people usually suggest, but there are several reasons for that. first of all, lift doesnt eat up vaccum or torque, the way duration does. there really is no good reason to run very light lift figures in applications with aftermarket heads. the E7TE's freeze up at .500. not even porting can fix that, CNC or otherwise. the Eddy heads, however, can keep on breathing.

those specs were with 1.6 rockers. i was suggesting 1.7, which would give you .521 on the intake and .532 on the exhaust. thats ideal for those heads, as cast. the valve will pass the point of maximum practical flow and velocity (right at the .500 range), and then hit it again on its way back to the seat. the most bang for the buck, not to mention the fact that the valve being snapped open quicker (thanks to the 1.7 rocker ratio, and its accelerated valve opening and closing speeds) is like a poor mans roller cam.

i seriously suggest you ditch the chip. get a mass air conversion. that way you can do whatever you want to the engine and not have to get a chip burnt for it every time. besides, some of those chips are questionable.

 

so do you think I should go with the cam from crower?

 

hey adam, you seem to be prety smart with cams, im building a 351w, stock rebuilt heads, 9:1 compression, headers, edelbrock performer carb and intake, this engine is gonna go in a big ugly 4x4 with 4:11 gears and 38s so i want power down low and as high towards 5000rpm as possible, its a regular hydrulic roler cam, what would you recomend?

 

badass, i think you should call CamMotion, but thats up to you. alot of people dont want to spend three hundred on a cam, and i can understand that. i can gaurantee you that youll be happy with that Crower Cam, but i dont have the resources and (more importantly) the computer programs to spec and grind the perfect cam, like CamMotion does.

i would suggest it on the condition that you use 1.7 rockers with it.

good luck.

 

i mean its a regular hydrulic flat tappet cam (its late here)

 

metallicafan, if you have stock heads, then you should definitely keep the lift below .500. are you absolutely positive that your windsor uses a roller cam? if thats the case, then i would suggest a cam like the Crane 444225. thats a 214/220 .483/.498, with a 112 LSA. thats a good bit of duration, but the stock heads respond more to duration than lift (hence the E Cam and all the other alphabet cams). the Crower Hi-Draulic cam, (PAW part number 15511) is another nasty roller that will make good torque. its 218/224 .468/.486 114 cam that works great in heavy vehicles.

however, i think its more likely that you meant a flat hydraulic. in that case, you actually have more choices.

a nice one would be the Comp Cams High Energy 268H cam. 218/218 .456/.456 110 cam. that will peak early enough to make the truck very enjoyable.

another excellent choice is the Extreme Energy 212/218 .477/.484 110 cam.

SVO part number M-6250-A332 is also a good choice here. 214/224 .472/.496 110.

if youve noticed, the hydraulic flats are generally cut on a 110 LSA, which is fine, because they usually end up in carbed vehicles. carbs dont have the slightest problem with 110 cams, while EFI systems occasionally do.

i would personally chose the Extreme Energy flat hydraulic in this case.

 

P.S. badass, ditch those headers. they will choke that thousand dollar set of heads you have until they pass about as much air as a set of P heads. you need a 1 5/8's primary.