Valve lifters…solid/hydraulic/roller tappet/flat tappet?

[blykins]

Originally Posted by olddog

Well I very much disagree with the planned gearing, and I personally wouldn't build a 302 for 8000 rpm. With that said, a 8000 rpm 302 is not all that radical. The SB Ford, likely the shortest deck height of all push rod V-8, is well suited to be a high rpm engine. The short deck gives the lightest of valve trains and the lightest rod. Your starting out with an engine that needs the fewest modifications to go more rpm. The only thing lacking is the block and rods. I would recommend good aftermarket rods and block. I would internally (zero) balance it too.

Let's put some things into perspective. Guys are spinning 4.25" stroke FE 6000 rpm. A 3" stroke has to spin 8500 rpm to achieve the same mean piston speed. Then we are talking a 4" bore compared to a 4.23" bore -- a much lighter piston. Now a 6.488" rod length verse a 5.090" (I don't know what the FE stroker rod is). Certainly the FE stroker has a much worse rod ratio. So the FE is turning higher piston speeds with a much heavier piston, rod, and wrist pin, with a worse rod ratio. I say a FE stroker turning 6000 rpm is a much more radical engine than a 302 turning 8000 rpm, from a rotating assembly point of view.

Now the FE has bigger, longer valves and springs. A longer push rod, and larger rocker, too. I do not have the weights nor the formulas to calculate valve geometry. However my gut tells me that 8000 rpm on the 302 will only be a little more challenge than 6000 rpm on the FE, not a huge difference.

I have spun 327 Chevy to 8000 rpm, with a stock bottom end, and aluminum roller rockers. Springs that came in the cam kit with solid lifters. I ran the crap out of it for a year with no problems. Maybe I was lucky. I sure wouldn't do it today. But the point is 8000 rpm on a 302 is not some insane, radical, or stupid idea. I believe NASCAR was turning FE engines 7000-8000 rpm back in the day.

Anyone know what Shelby and the others were turning the 289 in the races with the original SB Cobra? I expect they were getting every bit of 450 hp and turning them 8000 rpm or more.

What small blocks were turning in full race cars and in NASCAR has zero bearing whatsoever in this situation. This is a street car with a high rearend gear ratio, on pump gas, with low rpm manners required.

There's also one key difference: for the average home builder to say that he's turning 8000 rpm either means that he's got his distributor wired for a 6 cylinder, or he's making peak power at 5000 and he's turning it 3000 extra rpm. You wouldn't believe how many guys I run into that think they are making power at 8000 rpms.... Do you guys know how much head and cam is required to peak at 8000?

We need to get back on track here. Even if I built a 302 to turn 7000 and make peak horsepower there, it's not a good match for XB's application.

XB...

Again, no one is pro-stroker or pro-revver. I'm both. I use both. I cherish both. The point here (and I need to really type this in all caps) is to build the engine for the application!!!!

An engine that makes peak horsepower at 7000-8000 has nothing down low! Especially very small displacement engines!

[Gaz64]

Originally Posted by blykins

What small blocks were turning in full race cars and in NASCAR has zero bearing whatsoever in this situation. This is a street car with a high rearend gear ratio, on pump gas, with low rpm manners required.

There's also one key difference: for the average home builder to say that he's turning 8000 rpm either means that he's got his distributor wired for a 6 cylinder, or he's making peak power at 5000 and he's turning it 3000 extra rpm. You wouldn't believe how many guys I run into that think they are making power at 8000 rpms.... Do you guys know how much head and cam is required to peak at 8000?

We need to get back on track here. Even if I built a 302 to turn 7000 and make peak horsepower there, it's not a good match for XB's application.

XB...

Again, no one is pro-stroker or pro-revver. I'm both. I use both. I cherish both. The point here (and I need to really type this in all caps) is to build the engine for the application!!!!

An engine that makes peak horsepower at 7000-8000 has nothing down low! Especially very small displacement engines!

All very good points.

Some more info for Glen.

When selecting a cam, the quoted power range from the cam grinder is, eg: 3000 - 6000 rpm, not it's min and max but it's best operating range.

No cams are have a range of idle to 7000+ rpm.

And the higher up you go, the narrower the band becomes.

[Jerry Clayton]

Put a blower on it!!

[RICK LAKE]

zrayr Z. lets start with that Glen has a paper car and motor to start. Now lets look at facts
ford build 5 different 289 blocks, 1 was experimental in aluminum.
blocks "A","B","D" all are hydro lifters and get pumpup problems at about 6,200 rpms. Rods have small bolts in rod caps and main caps on the bottom end where a standard width. The blocks are all about the same with the metal that cast them. They where some 289 blocks that where stretched to a 302 but had thin clyinders and water issues. Skirts in the 302 blocks are .020" longer These motors all made about 195 to 225 hp at 5,000 rpms. com pression was from 10.1 to 8.75. your motor was 11.5 to 10.0 These motors had a limit of 6,000 rpms with a single point distributor. Valve springs where in the 170's seat pressure. This covers these 3 blocks now yours if you have a "K" block
Your block has larger rod bolts, higher nickle in the block, wider main caps. The cranks where hand picked and had the Brinell treatment done on them. The valve spring have seat pressure around 300 at seat with a SOLID camshaft and lifters. intake manifold aluminum. Biggest thing for turning 7,000 rpms was the larger dampener and counterweight added. With out all these things added to the "K" motor it wouldn't last turning 7,000 rpms. Dual points where needed also. Some of the motors had better valves. timing up to 35 degrees with this motor. the others where limited to less.
There is a RUMOR that ford did try and build some small blocks of aluminum. I don't have any solid info on this. Could have been for Shelby's GT-40 cars. Looking to save weight and increase power.
Hows that for a fairy tale I don't think that Glen has a "K" motor or block laying around in his back yard or he can go down the street and get one at a Pep boys or Auto zone. Maybe you have a spare to sell him??? Last thing is if you ran your motor at 700 rpms, it would break from the bad harmonics at this rpm. Rick L.

[zrayr]

Originally Posted by RICK LAKE

".............. if you have a "K" block
Your block has larger rod bolts, higher nickle in the block, wider main caps. The cranks where hand picked and had the Brinell treatment done on them. The valve spring have seat pressure around 300 at seat with a SOLID camshaft and lifters. intake manifold aluminum. Biggest thing for turning 7,000 rpms was the larger dampener and counterweight added. With out all these things added to the "K" motor it wouldn't last turning 7,000 rpms. Dual points where needed also. Some of the motors had better valves. timing up to 35 degrees with this motor. the others where limited to less.
There is a RUMOR that ford did try and build some small blocks of aluminum. I don't have any solid info on this. Could have been for Shelby's GT-40 cars. Looking to save weight and increase power.
Hows that for a fairy tale I don't think that Glen has a "K" motor or block laying around in his back yard or he can go down the street and get one at a Pep boys or Auto zone. Maybe you have a spare to sell him??? Last thing is if you ran your motor at 700 rpms, it would break from the bad harmonics at this rpm. Rick L.

you describe the K code motor fairly well, with only a few corrections needed:

!)* Hi-Po Blocks are no different in metallurgy than standard 289 blocks, no highER nickel content. All 6 bolt K code blocks had a C5AE-6015-A or -E casting code. Blocks installed in plain vanilla 289's may have the same casting number as well. Other than the main caps there's nothing to distinguish a K code block from an ordinary 289 (one can more readily find the Mexican 302 blocks with the same main caps).

2) Brinnell is a test for hardness, not a treatment. Ford did NOT do special castings or special metallurgy for the Hi-Po crankshaft.* It was merely tested for a minimum hardness.

3) Aluminum intake manifolds were only standard on the Shelby Mustangs. K code Mustangs got the plain vanilla Ford cast iron 4V intake.

4) the rods were also quite a bit stronger than the std. 289 rods, but not as strong as a Boss 302 rod. Ford eventually listed the Boss 302 rod as a service replacement for the Hi-Po rod,

5) valve spring pressure was rated at 247 lbs. at 1.31" Standard valve springs were rated at 161-180 lbs.

6) ignition timing on K code's, using '66 as an example, is 12 degrees BTDC at idle and another 28 degrees from the mechanical advance for a whopping 40 degrees BTDC at full advance.

*: loosely quoted from Tony Gregory's book "The 289 High Performance Mustang" now in it's 4th or 5th edition. Gregory has long been recognized as a premier authority of all things K code related.

As one point (p.8 in the 2nd edition) early on in his book Gregory states, "... All of these differences combined is what allow the Hi-Po to turn 8000 RPM's instead of only 6000 like a standard 289. The stronger main bearing caps hold the crank in place, the thicker harmonic balancer, hatchet, and flywheel assist in balancing the engine which assures less vibration and smooth operation. In short Ford made it a team effort to keep the bottom end together at high speeds."



However, you quite succinctly state the essence of what makes the K code 289 engine special. On the bottom end it's the bigger main caps and the bigger rod bolts along with the additional balancing they require. Upstairs it's the screw in rocker studs, heavier valve springs, and cast-in valve spring pockets in the heads, etc.

Complete Hi-Po engines are usually available on ebay, etc. and usually can be had for about $7,500 , but in need of a complete going thru. Many people go the Mexican block route and just build it up.

Z.

[olddog]

This is what I come up with on my dyno simulation program.
I used the best heads I had available. I assume 4V Cleveland or Boss style heads that morphed into ported NASCAR heads. As I said keep valve overlap minimal. I used a dual plane to keep the bottom end up, which did hurt the top end, compared to a single plane. I did not cheat and use open headers. The mufflers killed a 100 hp and forced more cam (especially on the exhaust) to get the top end. Duration is 225 intake and 250 exhaust @ 0.050" lift. Yes a very wide pattern split.

As you can see the bottom end torque is very respectable in the 375 lb-ft range, and overall fairly flat. 381 lb-ft at 2000 rpm is not going to be a total dog in the bottom end. The hp peaks around 7500 rpm at 506 hp, and is relatively flat from 7500 to 8500 rpm. 496 hp at 8500 rpm is only down 10 hp from the peak.

I suspect building a real engine to these specs would not actually produce the same results. Who knows if it would even be in the same ball park.

[xb-60]

Those two posts explain a lot. Thanks Rick and Z, and others.
The folders containing engine related information are getting heavier.
Cheers,
Glen

[xb-60]

Originally Posted by olddog

Are you serious olddog, or is this like Brent said, tacho wired for a 6cyl?
What's the story?
Cheers,
Glen

[olddog]

By changing to open stepped-tube headers, a tunnel ram intake with 1000 cfm on top, and keeping everything else the same, the Hp peaks at 665 hp in a flat line from 8500 to 9000 rpm and the 2000 rpm torque only drops to 350 lb-ft. However the torque curve is dropping fast as the rpm goes down, so the 1500 rpm torque might drop below 300, lb-ft (not charted).

[olddog]

Originally Posted by xb-60

Are you serious olddog, or is this like Brent said, tacho wired for a 6cyl?
What's the story?
Cheers,
Glen

To be fair, the head choice in this program I believe to be expert race ported heads. I expect to actually get heads that good would be in the $5000 range or more.

Now most experts (with far more experience than my reading books and playing with computer simulation software) will tell you that large port heads like that will kill the low end torque. Now, I will tell you that if you use a cam to take advantage of those head's top end power potential, they are absolutely right. It will give you a low end dog. However it is my theory that if you give up the top end power and keep the cam mild, the bottom end does not have to suffer.

I look at it this way. With supper good flowing heads, at low rpm the flow will do exactly what the cam tells it to do. If you have over lap, it will suck exhaust back into the intake like there is no tomorrow. If you close the intake valve late, the piston will shove air back into the intake, leaving the cylinder less than full. On the other hand, if you keep the overlap to a minimum and don't leave the intake valve open too long, these supper good flowing heads are going to completely fill the cylinders, giving excellent low end torque. You will give up top end power, but still have decent power due to the flow capability of the heads. From there you play the rob Peter to pay Paul game with the cam to strike the best balance. The heads allow a much milder cam that give a much flatter torque curve.

Buy going all out on the cam, tunnel ram, 1100 cfm, open stepped headers, I can get 900 hp at 11000 rpm, which drops the low end torque to 200 lb-ft. That is how big these heads are. This would be costly and tough to get your hands on. Not to mention trying to keep control of the valves. These are heads that should be on a longer stroke engine to keep the rpm down.

[xb-60]

Originally Posted by olddog

.... if you keep the overlap to a minimum and don't leave the intake valve open too long, these super good flowing heads are going to completely fill the cylinders, giving excellent low end torque. You will give up top end power, but still have decent power due to the flow capability of the heads. From there you play the rob Peter to pay Paul game with the cam to strike the best balance. The heads allow a much milder cam that give a much flatter torque curve.

The 'rag/mag' article I mentioned earlier obviously doesn't tell the whole story, but what I got out of that article was, I think, in line with what you're saying about decent (but not too big) heads and mild cam. And some compromise on my part on gearing.
Cheers,
Glen

[olddog]

Originally Posted by xb-60

The 'rag/mag' article I mentioned earlier obviously doesn't tell the whole story, but what I got out of that article was, I think, in line with what you're saying about decent (but not too big) heads and mild cam. And some compromise on my part on gearing.
Cheers,
Glen

I gave an extreme example of an engine to show that for enough money it likely can be done, but very likely has not been done. It just isn't the road that is traveled. Few if any builders are practicing in this arena. It is just too easy and too economical to go the direction that Blykins is pointing you, so that is where the crowd has gone. I have thought about these things because I'm an engine geek. People doing it for a living and standing behind their work do not have the luxury that I have. I haven't any skin in the game. It all just academic fun for me.

Yes. I do think you have to compromise in the gearing. If your making 500 hp at 8000 rpm and someone else is making 500 hp at 6000 rpm, to get the same performance your going to have to be geared to turn 8000 rpm at the same mph that the other guy is only turning 6000 rpm. Most guys running big FE are geared 3.5:1, some a little higher some a little lower. Your going to have to have a rear ratio at least 3.5:1 and more likely closer to 4:1 to have decent acceleration, with the low torque of a typical 302. Then the cruising rpm is going to be too high to enjoy the ride (noise). I would go with a 5 speed. The overdrive is very nice. I know that is not what you want.

Or spend a small fortune developing my magic engine. I'd expect it would take a half dozen cams to actually achieve the magic engine. Maybe a couple or three tries on the heads, too.

[zrayr]

Originally Posted by olddog

"....Now most experts (with far more experience than my reading books and playing with computer simulation software) will tell you that large port heads like that will kill the low end torque. Now, I will tell you that if you use a cam to take advantage of those head's top end power potential, they are absolutely right. It will give you a low end dog. However it is my theory that if you give up the top end power and keep the cam mild, the bottom end does not have to suffer........."

I'm no expert, as all that know me will attest to, but the one thing I think you are overlooking is the relationship of small ports to intake charge velocity. If the intake ports are not matched to the rest of the engine, i.e. too big, the velocity will drop and the gas will fall out of suspension. The same thing happens when you try to put a "too big" carb on a relatively small engine. A mild cam will mitigate this somewhat as you suggest, but not enough, and throttle response will suffer and you will end up with a huge bog that can't be tuned away.

Z.

[blykins]

Originally Posted by zrayr

I'm no expert, as all that know me will attest to, but the one thing I think you are overlooking is the relationship of small ports to intake charge velocity. If the intake ports are not matched to the rest of the engine, i.e. too big, the velocity will drop and the gas will fall out of suspension. The same thing happens when you try to put a "too big" carb on a relatively small engine. A mild cam will mitigate this somewhat as you suggest, but not enough, and throttle response will suffer and you will end up with a huge bog that can't be tuned away.

Z.

I would agree with that 100%. Add volume and flow, but take away velocity, and you end up with a port carrying a lot of inertia. A "slow" port is hard to get moving and is considered lazy until the higher rpms. If you don't have enough cam, it doesn't matter how well the heads flow, it won't pull the rpms that you want. It's true that you need less duration as head flow increases, but that doesn't mean that you can have a 600cfm head and a 205° duration and spin to 7000. (Just for example's sake...)

The dyno sims are a great "ballpark" tool. Unfortunately, Desktop Dyno and EA Pro show about 7-8% high compared to the actual dyno that I use. Desktop Dyno seems to be WAY off when it comes to torque numbers as well.

There's NO way that a 302 set to peak at 7000-7500 will have a flat torque curve settling around 400 lb-ft. An't no way. An't gonna happen.

You also have to look at it this way....dynos are cool for breaking in an engine and seeing what kind of power it puts down, but at the end of the day, you can't get on it and drive it. A dyno gives no indication whatsoever as to how the engine will be on the road, in a car, with a transmission and rearend behind it. It gives no indication of how much you'll have to slip the clutch taking off or how fussy it will be cruising at 1500 rpm.

What you would see in reality with this type of combination would be a torque peak at around 6000 rpm, with probably around 100-150 lb-ft available at cruising rpms. The curves would look more like a steep hill instead of having any flatness to them at all.

[olddog]

I’ll make a few comments on fuel falling out of suspension. I recall having some SB engines that would load up at idle from fuel droplets forming on the walls. They had factory stock heads and intakes, but radical cams. So in those cases, it wasn’t from the ports being too large.

So let’s examine why a radical cam might be the root cause. Liquids have a hard time existing in a vacuum, especially gasoline. I think it’s called vapor pressure. A high valve overlap cam may idle at 10”Hg of vacuum, where a mild cam may idle at 19”Hg. I think a perfect vacuum is about 27”Hg, if memory serves. The higher the vacuum, the less likely fuel is going to drop out of suspension and form droplets on the walls.

With long intake duration, the intake valve may not close until the piston is well on its way up on the compression stroke. Often the intake valve does not close until 50, 60, or more deg after bottom dead center. At an idle this can cause the air to blow back up into the intake – reversion. So, at some point the velocity goes to zero before it reverses. Now if you want to talk about low port velocity, it doesn’t get any lower than none. You’re not going to avoid this no matter how small the ports are. Radical cams bring the port velocity to a complete halt at idle, regardless the port size.

Now the intake valve spends almost ¾ of it’s time closed. Then why isn’t a big puddle of fuel forming in the port and intake runner at idle during this time, if low velocity is the cause of the problem?

Now let’s talk about port velocity, when an engine is at an idle. A 350 cid engine at 100% efficiency is only pulling in 600 CFM of air at 6000 rpm. At 600 rpm that is only 60 cfm, with the throttle wide open. Close the throttle to let it idle, and where is the flow? Maybe there is 5 to 10 cfm at an idle, on a typical engine. Port velocity is practically nonexistent at an idle anyway.

I do not buy that large ports will cause fuel to drop out of suspension at idle. I think radical cams cause it, and big ports get blamed for it. After all, who puts large port heads on an engine without sticking a big bump stick into it, now days?

The big block engines in the 50’s and 60’s typically had large ports and mild cams. They lugged around big luxury cars, and had stump pulling torque from off idle to ~3500 rpm. They purred like a kitty cat at idle. Not all of them were large displacement. The FE started out at 331 cid.

However, I do think too large of ports will cause a bog or a lag in torque coming off idle, similar to turbo lag. No doubt it is hard to make low and mid range torque, when the ports are too large, but the cam choice can make it much worse.

[Barry_R]

Step away from the keyboard slowly with your hands clearly visible and have somebody disable and remove the dyno simulation software before anybody gets hurt.

Many of the original poster's goals can be reached - but not easily and not within the context of an original looking engine with iron heads. I've done 433 inch FEs that made over 500 ft-lbs at 2500 and nearly 700 horspower at 6500. But they were and are very highly developed engines using the very best possible parts. Old parts on an old platform ain't gonna get you even close.

Heads will need to be aftermarket alloy - like the aforementioned AFRs or Cleveland style CHI parts simply in order to get the necessary flow. No iron head factory can even come into the same zip code.

Cam will need to be short in duration compared to something race oriented - but bigger than any factory piece ever was - and have a fair amount of lift. A stock Ford 302 cam ain't going to get power at 7000. Does not matter how many times it gets written or how bold the type. Simply won't happen in the real world.

The only way I can see to get anything approaching low end driveability in a 7000 RPM package is to abandon the carburetor in favor of EFI. I worked at Holley for eight years and love those things dearly - but the only way to generate torque at low RPM with a large cross section port is to add length. On an SBF the only way to find runner length is to get the air metering away from the center of engine.

Just for backdrop - those luxury barges from the 60s were turds compared to anything modern from a performance perspective. They ran slowly, lumbered to 17 or 18 second 1/4s, and got miserable single digit mileage. Sure they idled smooth. Everything looks better in the mirror. My wife's minivan will outrun a 460 powered Lincoln...

[blykins]

Did you read all 12 pages Barry, or did you go out and buy the Cliff Notes?

[RICK LAKE]

blylins Brent it's snowing and he just got done with Engine masters. Having a LITTLE gas fumes withdrawal. He will be OK. I can't wait for the fairy tale to become a book and movie, The little engine that _ _ _ _ _ maybe. Rick L.

[xb-60]

....you guys making fun of me?
Cheers!
Glen

[RICK LAKE]

xb-60 No Glen you asked question and guys have tryed to give the best info they have. I will be unreal to think you can build a motor with the specs you want. The cost on this motor will be large also. I did have an idea about this, Fine a set of gurney westlake heads and intake, this will get you into the ball park. As other have said, running an FI system might have to be also done. Rick L. Ps you can start this trip by looking and buying a "k" block. Nothing more than .030" over bore and the correct main caps to THAT block. Need soda and popcorn, going to work. Rick