[COBRA5LADDICT]

I’m always amazed by the wealth and knowledge and experience here so I want some opinions on my 302 build.



I’m building a budget roller 5.0/ 302 to go into my 1965 convertible with a 4 speed try y headers, 2.25 exhaust and 3.25 gears. The car won’t be raced. It’s a fun BBQ cruiser with some punch to not be embarrassed at the stoplight next to a Honda Civic. I have a 100% stock roller 5.0 shortblock out of a 1999 explorer. It was reasonably low mileage so it got a hone job, new rings and a polish on the crank. It also has the original / factory explorer roller cam installed. The heads were gt40P and I didn’t want to fight header issues so I sold them to a buddy. I need some heads and due to budget I believe I’ve settled on the flotek 203-505 58cc heads with 1.94/1.54 valves. If I keep the cam reasonable I can probably avoid any fly cutting with the smaller valves and lift at or below .510. When I have all the parts I will check piston to valve clearance but I really hope to not have to fly cut. I have a performer 289 intake (its not ideal but its what I already have. If I’m leaving a lot of meat on the bone, I will upgrade to the performer RPM , but if its only a few HP I probably won’t. The couple of questions relate to cam selection. I’ve been reading up and it appears that in an ideal world, a cam selection for a carb / dual plane intake would warrant a smaller lobe separation vs the 112* for most EFI roller applications. Any truth to that? would the difference be negligible? Any thoughts on cam selections? I plan to run a summit carb (500 or 600cfm)

Flo-Tek 203505 Small Block Ford Aluminum Cylinder Head

What I want. Is a reasonably mannered profile that is fun to drive on the street. My target is pretty flat power / torque band from idle / 1500-5500 rpm max. I don’t really have any interest in spinning it beyond that. I live in Denver so my altitude is 5,500 ft above sea level. In looking at the powerband for the performer 289, its all done by 5,500 RPM which is fine because that’s as tight as I want to spin it.



One off the wall idea would be to use the explorer cam with 1.7 ratio rockers (I don’t own the rockers yet) to give me a tad of lift. Would the additional lift of the 1.7 rockers be enough to make power to 5,500 rpm? Any thoughts on this?

 

[wilit]

Just FYI, lift isn't the end-all determining factor in piston to valve clearance. I'm running an XE274HR (.555in/.565ex) on stock style flat top pistons with small valve reliefs and Trick Flow TW170 heads. I've got .110" clearance on the intake with a .040 head gasket.

You could always go with a Trick Flow stage 1 cam and most likely will be pretty safe, but by today's standards, that's a small cam.

 

[Lizer]

Whatever you decide, you need to make sure your cam, intake, and heads are matched and in concert with each other.

Also don't get caught up on high rpm. I'm not sure why you care about being able to reach 5500 rpm if you want a BBQ cruiser or not getting embarrassed at a stop light. What you're actually wanting is torque, so you need to be looking at configurations that will be making the most low end power.

 

[DIHLON]

For not a whole lot more money, you could get the AFR Enforcer heads. I'd take those over Flo-tek's any day. Is your 4 speed manual or auto? If auto, you may need a torque converter with more stall if going with a bigger cam.

 

[66coupe289]

You don't have to do too much to those Explorer engines to make the respectable performers. @Huskinhano might pipe up as he is happy with the performance of his.

 

[66coupe289]

For not a whole lot more money, you could get the AFR Enforcer heads. I'd take those over Flo-tek's any day. Is your 4 speed manual or auto? If auto, you may need a torque converter with more stall if going with a bigger cam.

Agreed, the AFRs come with better hardware.

 

[Woodchuck]

What you're going to have to contend with is the quench area which, with the stock 5.0 piston being .016" down in the hole is, at best with a .027" MLS head gasket, .043" and, with a .030" gasket, .046". I wouldn't want to go any wider. Believe it or not, the Explorer "P" cam (also used in 5.8's) #F4TE-6250-BA, is a great grind for low rpm torque, idle quality and fuel economy, but is all done making power at about 4,800 rpm. Great if you're building a "cruiser" with a stock automatic transmission and relatively tall gearing. We chose a bit more aggressive M-6250-E303 for our 289 build to extend that power band upward without sacrificing too much on the bottom end. As far as cylinder heads go, you get what you pay for.... If you look at specs, particularly EXHAUST flow, as that is where SBF's are deficient, and why the "P" heads work so well, the AFR165 kicks serious butt. The "Enforcers" are, in my mind, a waste of money without port work and same with the Flo-Tek. The AFR #1399 flows more at .300" valve opening than the Flo-Tek does at .500"!

Anyhow, pick the components that are going to suit the rest of your "configuration" and driving style. If I was building a 302/5.0 with a stock bottom end and pistons I'd build it to make torque and keep the peak HP below 6,000 rpm.

 

[Ackbar00]

Facebook marketplace is your friend. Just search there and buy used stuff local.


I got a B-Cam and Edelbrock performer heads for $800. Brawer 650 carb, Edelbrock 289 intake I had from previous 302. T-5 and 4.00 gear. Ran a [email protected]

 

[COBRA5LADDICT]

For not a whole lot more money, you could get the AFR Enforcer heads. I'd take those over Flo-tek's any day. Is your 4 speed manual or auto? If auto, you may need a torque converter with more stall if going with a bigger cam.

Enforcer heads have a 2.02 valve and likely will result in piston to valve issues. They definitely outflow the flotek but Also they have a 64cc combustion chamber vs the 58cc of the flotek.

Whatever you decide, you need to make sure your cam, intake, and heads are matched and in concert with each other.

Also don't get caught up on high rpm. I'm not sure why you care about being able to reach 5500 rpm if you want a BBQ cruiser or not getting embarrassed at a stop light. What you're actually wanting is torque, so you need to be looking at configurations that will be making the most low end power.

simply mentioned 5,500 rpm as a parameter.. i likely wont turn it past 5k.. ever

 

[COBRA5LADDICT]

What you're going to have to contend with is the quench area which, with the stock 5.0 piston being .016" down in the hole is, at best with a .027" MLS head gasket, .043" and, with a .030" gasket, .046". I wouldn't want to go any wider. Believe it or not, the Explorer "P" cam (also used in 5.8's) #F4TE-6250-BA, is a great grind for low rpm torque, idle quality and fuel economy, but is all done making power at about 4,800 rpm. Great if you're building a "cruiser" with a stock automatic transmission and relatively tall gearing. We chose a bit more aggressive M-6250-E303 for our 289 build to extend that power band upward without sacrificing too much on the bottom end. As far as cylinder heads go, you get what you pay for.... If you look at specs, particularly EXHAUST flow, as that is where SBF's are deficient, and why the "P" heads work so well, the AFR165 kicks serious butt. The "Enforcers" are, in my mind, a waste of money without port work and same with the Flo-Tek. The AFR #1399 flows more at .300" valve opening than the Flo-Tek does at .500"!

Anyhow, pick the components that are going to suit the rest of your "configuration" and driving style. If I was building a 302/5.0 with a stock bottom end and pistons I'd build it to make torque and keep the peak HP below 6,000 rpm.

Great feedback.. i agree that the AFR renegade 165 is a far superior head to the flotek but its probably way more head than i need or intend to use. would i be better off skipping the flotek and freshening up a set of GT40's? picking htem up in a junkyard and rebuilding would be as much as the flotek heads.

i love that you mention building for torque. That's been my idea, that is what is fun to drive.. precisely why i mentioned the possibility of running the explorer cam with 1.7 rockers to use all that torque, and use my performer 289 intake.

 

[66coupe289]

i likely wont turn it past 5k.. ever

The only time mines sees 6K is when I drive it. Rev limiter set at 6,200 in case a shift is missed.

My 289 is rpm limited due to the stock, non-k code, bottom end and hydraulic cam.

 

[66coupe289]

Great feedback.. i agree that the AFR renegade 165 is a far superior head to the flotek but its probably way more head than i need or intend to use. would i be better off skipping the flotek and freshening up a set of GT40's? picking htem up in a junkyard and rebuilding would be as much as the flotek heads.

i love that you mention building for torque. That's been my idea, that is what is fun to drive.. precisely why i mentioned the possibility of running the explorer cam with 1.7 rockers to use all that torque, and use my performer 289 intake.

The Performer RPM makes as good of torque or better than the Performer at darn near any rpm.

 

[Grimbrand]

1.7 rockers aren't as great as you might think. They are usually rollers, which means they have needle bearings that often fall out into your pan. They also tend to make the valvetrain chatter a little. The roller part doesn't even reduce friction enough to make any extra power until you are past 5k RPMs anyway! I'd stick with stock 1.6 sleds, for a cruiser.

If you do go with aftermarket heads, the AFR Enforcers come with much better hardware than FloTeks, and are not much more expensive when you compare them. You can always buy bare heads, and put in your own good valves, rockers, springs, etc. but the package deal you get with "complete" heads is hard to beat.

Your GT40 heads are basically like the old '69-70 351W heads, but with larger chambers that have lower compression. They are probably not worth putting a ton of money into, although they are a little better than the common E7TE heads.

For a budget build though, they're not terrible at all! I think with a decent intake, Summit 500 CFM carb, and some headers, you might be surprised at how fun your car is. Controllable, but eager to make tire smoke. Getting your timing set properly will make all the difference.

Heads are probably the first place to look for addtional performance with your build, but stick with small valves to compliment your low RPM torque approach. Not bigger than 1.94s, with nice small runners for good velocity. Keep an eye out on Facebook Marketplace and local sale sites, and you can sometimes find good ported stock Ford heads for sale cheap. I just unloaded a set of ported '69 heads that flowed 221 on the intake side @.50 lift, and those are going to make a guy very very happy. Hardened seats, screw in studs. I sold them for only $500, and they had about 2k worth of work in them. A good set of small aluminum heads, used, would be a great buy too!

 

[Helmantel]

View attachment 879701

The only time mines sees 6K is when I drive it. Rev limiter set at 6,200 in case a shift is missed.

Don't understand this fascination for building a small block that falls on its face past 4500 RPM either

 

[G's 70]

Do you have the stock explorer heads? They're not bad for a low budget build.

 

[66kcar]

As mentioned above, it’s the combination of parts that make the most power per dollar.

if getting aftermarket heads, ditch the performer intake

if running factory GT-40 heads, keep the intake as it won’t matter anyway

keep the carb small, like 500-600 cfm

I have a roller 302. I went E cam, an old Shelby intake, GT-40 heads with a bit of porting and roller rockers, good headers are worth the money. Put some old HiPo parts on it and it looks like a day 2 289.

 

[COBRA5LADDICT]

Do you have the stock explorer heads? They're not bad for a low budget build.

I don’t have any heads.

 

[bmcgc]

If it is an around town cruiser, stick in a set of 3.50 gears, it will feel like another 100hp.

 

[Westmus]

Any thoughts on cam selections?

I would keep the stock explorer cam until I had actually driven the car. I guess it works much better for your intended use than you may think. Cams usually pulls much higher rpm than people expect when combined with some good flowing heads. A bigger cam are about moving the power band upwards. You gain more rpm and peak power, but do also remove some "tire-smoke" torque down low.

 

[ArizonaGT]

If it is an around town cruiser, stick in a set of 3.50 gears, it will feel like another 100hp.

That^ absolutely. Or maybe even deeper than that (3.70/3.89/4.11). Depends on how much you like getting mashed back in the seat 😉