Another Cam question - Isky max 1

[Ol' Ron]

I use the earley gers on all my bills anyway. However I don;t think the gears make that much difference, check the back lash. I also use the late ignition system. Yjis allow th eloadamatic distributor on the early engine with the right carb. Allot of people rejevt this distributor, However if in the proper working order, with the right carb. It's a very inexpensive improvement over the early ignition system. and you can upgrade to a chevy dist. for multi car systems.

[Bored&Stroked]

The early gears had the teeth angle opposite of the later gears (cam/crank). This forced the thrust toward the block, instead of toward the timing cover. The later gears pushed the thrust towards the timing cover and the end of the cam had a polished surface that rode on a place on the cover as a solid "bump stop". I believe the reason for this was for timing control - such that under load the distributor gear and cam drive gear were in steady alignment (at the front) and this kept timing fluctuations to a minimum.

But, as Ole' Ron mentioned, if your backlash is on the low-side of the spec (about .003 to .004), then the cam really doesn't move back/forth much anyway. Like Ron, I prefer to run the earlier gear sets on most everything.

Gasket Thickness: There are some repop timing cover gaskets that are THICKER than stock - about .015 to .020, these increase the cam backlash to over .010 - which fubars your timing control. I've seen this is some Speedway brand gasket sets. The stock gaskets were about .008 thick. Always measure your backlash with the gasket you're going to use.

On racing engines I usually "tune" the backlash with no gasket - and run just a bead of silicone sealer instead of a gasket.

[Step-down]

When I used a degree wheel on a Max 1 it was off . Slotting the timing gear wasn’t a option for me .
Had Pete grind me a cam using a stock Ford cam and very happy.
About to send him another .

[Ol' Ron]

How many peop;e hav run the 77B cam. I had one but used it in a friends engine. Many years later he sold it (Never used it) New owner loves it. Be nice to have a comparison .
Gramps

[38 coupe]

I have a friend with a 77B in a +.040 bore 239 in a 3/4 ton truck. It runs ok, but isn't anything to get excited about. I like the EAB in my other friends +.060 bore 255 Mercury engine a lot more.

[Brian]

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Cam selection is a bit of a compromise; the efficiency of performance cams tends to push the RPM's of the engine up, with a corresponding lose of performance [from stock] in the lower rev ranges. I tend to cam and engine depending on it's ultimate use; if you are going to do the majority of your driving at, say, 60 MPH, you want a cam that is most efficient at those particular revs, say, for example, at that 60 MPH speed the engine is turning 2200 RPM, what is the point of running a cam that comes on at 4500RPM?
I think many owners tend to 'overcam' their engines, for any number of reasons. The whole picture needs to be carefully looked at; ultimate use, engine mods, rear axle gearing, weight of vehicle, transmission ratios etc....
All that said, I like the Isky 88 grind, in my particular application I want a cam that cruises comfortably at 70 MPH, with the power in reserve to perform overtaking manoeuvres etc. The downside is that it can tend to be a bit 'jerky' trying to drive at 20 MPH in top gear, as opposed to the silky smoothness of a stock engine in the same application....but the stocker has run outta breath at 60! at's all a trade off.

[Pete]

You can have it all with a turbine.

[V8COOPMAN]

Originally Posted by Pete

You can have it all with a turbine.

.... EXCEPT for the time it takes to 'spool-up'!

Coop

.

[38 coupe]

Originally Posted by Brian

Cam selection is a bit of a compromise; the efficiency of performance cams tends to push the RPM's of the engine up, with a corresponding lose of performance [from stock] in the lower rev ranges. I tend to cam and engine depending on it's ultimate use; if you are going to do the majority of your driving at, say, 60 MPH, you want a cam that is most efficient at those particular revs, say, for example, at that 60 MPH speed the engine is turning 2200 RPM, what is the point of running a cam that comes on at 4500RPM?
I think many owners tend to 'overcam' their engines, for any number of reasons. The whole picture needs to be carefully looked at; ultimate use, engine mods, rear axle gearing, weight of vehicle, transmission ratios etc....
All that said, I like the Isky 88 grind, in my particular application I want a cam that cruises comfortably at 70 MPH, with the power in reserve to perform overtaking maneuvers etc. The downside is that it can tend to be a bit 'jerky' trying to drive at 20 MPH in top gear, as opposed to the silky smoothness of a stock engine in the same application....but the stocker has run outta breath at 60! at's all a trade off.

I think Brian defines the situation very well. In support of what Brian is saying I will attempt to add information for other's use.

Edit:
Initially I had intended to include a graph showing the data from JWL's cam test published in his Flathead Facts book (page 73). Then I realized by doing that I would probably violtate the copyright from his book, so I am not including that. The point of JWL's cam test data is the break over point from a stock 8BA cam to a Max1 cam is about 2700 rpm. That is, below 2700 rpm the stock cam makes more power than the Max1. I find this interesting since I prefer to gear vehicles so they are spinning about 2700 rpm at my maximum expected cruising speed.

What I have included is a table with rpm at speeds between 1 and 100 miles per hour for many driveline combination for Early Ford V8 era cars and 1/2 ton commercial vehicles. I included any combination that could reasonably be achieved with mostly bolt in components and factory rear axle ratios. I apologize that the graph is small print, so I also attached a pdf of the same that you should be able to download and zoom in on for easier reading.

As an example I want to be able to drive 80 mph in a stock appearing 1938 Ford while maintaining smooth around town driving. For people excited about my cruising speed please note that I live in Texas, 80 mph is 5 mph less than our highest freeway speed limit at the time I am writing this post; rural Texas two lane highways are frequently a 70 mph limit. Looking at all the drivetrain options I will choose either a 4.11 with Columbia or a 3.78 with Columbia and drive it with a ≈260 cubic in 24 stud engine.

[36coupe]

Originally Posted by Ol' Ron

How many peop;e hav run the 77B cam. I had one but used it in a friends engine. Many years later he sold it (Never used it) New owner loves it. Be nice to have a comparison .
Gramps

I have one 221 bored out to 3-3/16”, merc crank, 34 intake, 81a heads, stromberg carb and stock crab distributor
Budget build. Haven’t got it on the road yet. Chassis is complete, hope to get the body done this winter.
I also have a 8CM cam that I cut the gear off and had slotted.
Both cams pretty similar on paper

[Bored&Stroked]

BTW: If you take a later 49-53 cam and chop the nose/snout off and slot it, you should also plug the oil pressure hole that was designed to lubricate the front of the cam when it pressed against the timing cover. It creates an oil pressure leak (not a huge one) - but one none the less. Also, why throw more oil down into the area where the front main seal needs to deal with it.

[tubman]

Originally Posted by 38 coupe

....I find this interesting since I prefer to gear vehicles so they are spinning about 2700 rpm at my maximum expected cruising speed.

I have also found that 2700 is about as high as you want to turn these things for any period of time.

[flatjack9]

I run around 2500 rpm which is 73 which is 73 mph.

[Pete]

Originally Posted by V8COOPMAN

.... EXCEPT for the time it takes to 'spool-up'!

Coop

.

That is probably a function of the particular turbine in use.
I drove the 32 roadster with the 200 hp Boeing turbine in it and when you mashed the throttle, the wheels started spinning instantly. It was quite violent at low driving speeds if you wanted it to be. It was/is a really neat car.

[Pete]

Originally Posted by V8COOPMAN

.... EXCEPT for the time it takes to 'spool-up'!

Coop.

That is probably a function of the particular turbine in use.
I drove the 32 roadster with the 200 hp Boeing turbine in it and when you mashed the throttle, the wheels started spinning instantly. It was quite violent at low driving speeds if you wanted it to be. It was/is a really neat car. Remember, that was a "free" type turbine. That is, the primary and secondary wheels are not connected.

[Tim Ayers]

Originally Posted by Pete

That is probably a function of the particular turbine in use.
I drove the 32 roadster with the 200 hp Boeing turbine in it and when you mashed the throttle, the wheels started spinning instantly. It was quite violent at low driving speeds if you wanted it to be. It was/is a really neat car. Remember, that was a "free" type turbine. That is, the primary and secondary wheels are not connected.

Interesting, Pete. Any chance you still have picts? I love seeing how guys lay out creative thinking like this. By "free" type turbine, are you referring to a compound-type turbo?

I can only speak of the LS Chevy crowd that is using those HUGE Chinese turbos to get crazy HP out of these motors. From what I gather, there is little turbo lag with these as well.

[Pete]

Originally Posted by Tim Ayers

Interesting, Pete. Any chance you still have picts? I love seeing how guys lay out creative thinking like this. By "free" type turbine, are you referring to a compound-type turbo?

I can only speak of the LS Chevy crowd that is using those HUGE Chinese turbos to get crazy HP out of these motors. From what I gather, there is little turbo lag with these as well.

We are talking turbine here, NOT turbo. This is a gas turbine like used in many applications such as helicopters. It has a shaft output, not thrust as in a winged aircraft application.
The 32 roadster should be easy to locate somewhere on the internet. It is on display now in the Lemay museum. As I recall, the guy that put the turbine in originally got the car from Preston Tucker's son.

[V8COOPMAN]

Originally Posted by Pete

We are talking turbine here, NOT turbo. This is a gas turbine like used in many applications such as helicopters. It has a shaft output, not thrust as in a winged aircraft application.
The 32 roadster should be easy to locate somewhere on the internet. It is on display now in the Lemay museum. As I recall, the guy that put the turbine in originally got the car from Preston Tucker's son.

This is the Chrysler Turbine Car that proved to be very slow on the 'spool-up' from low RPMs, one of its major operational drawbacks. Yes Pete, big difference between TURBINE & Turbo(charger).

Coop

[Pete]

Maybe the reason the roadster was so quick was the power to weight ratio.

[Tim Ayers]

Originally Posted by Pete

We are talking turbine here, NOT turbo. This is a gas turbine like used in many applications such as helicopters. It has a shaft output, not thrust as in a winged aircraft application.
The 32 roadster should be easy to locate somewhere on the internet. It is on display now in the Lemay museum. As I recall, the guy that put the turbine in originally got the car from Preston Tucker's son.

Ah, got it. Makes sense now when you said 200hp Boeing. Now I’m really intrigued