Inliners International Forums General Discussion Hi Performance Cloyes Gearsets

In my research I'm seeing that Cloyes has already discontinued the 8-1016 and 8-1018 at least on their website. I know there are plenty still around. Looks like the only one they still make is the 2528S. http://cloyes.mycarparts.net/products/Cloyes-2528S?product_application_id=13394200090

The discontinued 8-1016 and 8-1018 are under a list of "Discontinued HP Items with no suggested alternate". I'm leaning toward the 8-1016 just because I figured it wouldn't whine as much plus it is adjustable. We had one in there from Clifford but lost it when we did another rebuild. Anyone have any recommendations? I'm concerned the 8-1018 will be too loud.

2516S will get you a timing set for 216, 235 and the Jimmy's from Autozone.

This is for a 292.

Does anyone have any recommendations on another gear set BESIDES Cloyes that would be of good quality?

Atozone # 2516S = https://www.autozone.com/internal-engine...608_95254_12256 Look under vehicle fitment.

216-292 Chevy sixes, 228-302 Gmc sixes, 153-181 Chevy,Mercruiser, OMC, Volvo marine fours,151 Iron Dukes are the same. Comp Cams, Summit, Jegs, Melling......... Stay away from the fiber cam gear.

Hmm, I didn't realize there were so many applications that would share the same gear set. Thanks.

I just always thought Cloyes was the best quality for these and now they're discontinued. It's kind of disheartening.

There are probably only a couple if manufactures that make them all. About 90% of the cam bearings used in the US are made by Dura Bond in Carson City, Nevada no matter what the box you get says.

Hold on there. The gear sets for the 216, 235 and 261 do not interchange with the sets for the 194, 230, 250 and 292. The crank gear might be the same but the cam gear is different. So are the thrust plates.

That makes sense because the one linked above says it didn't fit the 292. The number for it is 2528 like I said in my first post. Anyway, thanks for the input gentlemen. Seems like in reading Santucci's book he mentions only use Cloyes but I just wasn't sure what else was available and as good of quality.

Several of the cam manufacturers now offer competition gear sets for these engines. Some of them are adjustable.

I found some with alternate key positions, but none adjustable.
Got a link?
Thanks.

Show me the difference. If there is any it's with the older engines and it's probably a timing mark thing or sets with fiber cam gears. All of the newer series are the same gears sixes or fours.

The alternate keyways and using offset keys are the means of adjustment I was referring to. Didn't mean to mislead.

No offense, thanks.
Too bad, considering how much trouble it is to change the key there might be a market.

I am not sure what the 292 set number is, but the set will include a 2526 aluminum cam gear, and a 2527 steel crank gear. The 235/261 set that is the 2516S set is comprised of a 2514 aluminum cam gear and a 2501 steel crank gear.

The thrust plates for the 230-292 are .139 thick, for the 235/261 they are .187 thick.

I forget of the top of my head right now, but I think I have this right, you can tell the difference in cam gears by putting a straight edge flat across the gear. The hub on the 235/261 cam gear will be the same height as the outer edge of the gear, for the later cam gear, the hub is raised.

This is interesting. I can not remember where I got the information I posted earlier. I've got some old parts books I need to go through. I also have some old engines and gears setting around.

There may be some cross over for the 250 motor. The cam gear 2526 and the crank gear as either a 2501, the same crank gear as the 235/261, or 2527, the same as a 292. These part numbers are from notes I kept on some of the motors I was building a number of years ago. I think I will see if I can dig out my old parts book and confirm.

All I could find was the part number for the entire gear SET.

I looked up 3 Sealed Power gears on line. I know this is not the complete answer but it does indicate a LOT of interchange. There were lots of interchange numbers from other companies. The engines listed were their listing but it about covers it. The years tell the story. Sorry, I did a table but it won't post and when I type it out it changes when I post.
Basically #221-2500 fiber cam gear 216,235,261,228-302n GMC 1937-1963.
#221-2526 Aluminum cam gear engines include 250, 292, 153,181 from 1963-1989.
#221-2537 steel crank gear All Chevys 151-250 1938-1993

This one screws up to but here it is anyway.

I can not post my table but here are 3 links that give a lot of information about each gear.
221-2500
221-2526
221-2537

Has anyone any ideas on how it may be possible to modify an existing gear set to be adjustable on the engine? This would mean separating the hub from the tooth row (inner and outer circles) to allow the gear mesh to remain in place while rotating either the crank or cam (probably the cam since it's larger).
I've sen cam drives for other engines which had plate over-laying the interface (separation line) which bolted to both parts, and the position was fixed with a dowel. This could be inserted in several positions, all of which were smaller increments than a single gear tooth (13.33°) to both correct errors and allow fine tuning with the cam in place.
I don't think there's enough market volume to develop it as a commercial product, but there might be enough interest to make 10 sets?

Wouldn't one tooth on the cam gear be 6.66 degrees on the cam? Or do you figure it from the crank side? It's pretty easy the set up and get close enough when building an engine but changes later can be a pain. Keeping an adjustable gear in place would be tough and the results of a failure could be expensive. It is fun the think about though. With our press on cam gears maybe something in the hub or some kind of wedge?

The first thing to do will be to make the timing cover easily removable.

Offset keys for the crank gear and making the gear removable would be the simplest solution.

The coolest solution would be to produce a two piece cam gear that consists of a press-on flange with a locating dowel and a separate gear that has a two or three bolt outer gear with bushings for the dowel to allow adjustments like on the racing gear sets for big and small block GM V8s.

A steel inner flange with studs or special flat head bolts with allen or torx sockets could work. This would allow a timing cover with an access plate to allow adjustments by possibly removing the water pump and the access plate. In certain circumstances you wouldn't even need to pull the water pump!!!

Interestingly enough, at one time cloyes use to make a neat three position timing set for the 235/261 motor. Let you set the cam up straight, 2 or 3 degrees advanced or retarded (I forget which now) Clifford carried them for years. I have a set on a 235 I built way back in 84 or so. Back in 2011 or 12 that same gearset was still on Clifford’s website and I ordered a set. What I got was a standard engintech set. I spoke to Larry, he took them back, and told me that cloyes was not making them any longer. I called cloyes and they confirmed they were not making the adjustable set any longer. My guess is that we would need a pretty good number of orders to make it worth their while to make a run of those gears again.

It's the same 13.33° for both (720° ÷ 54 teeth = 360 ÷ 27 teeth) because of the cam turning 1/2 speed with twice as many teeth. I'm sure this is a good compromise of maximum error vs. smaller teeth (weaker) but it makes corrections by skipping a tooth an "extreme only method".

Here's a Ford 2.3 liter L4 with a cam drive using a face plate using bolts in slots (Racer Walsh product) securing the hub to the pulley which are simply tightened when the cam is properly phased, works at 8,000 RPM, but having pin positions would make it easier to tweak by using the stock Chevy marks, then identify how much change you need by pin position (viz., -4°, 0°, +4°, etc.) since any large change could begin with the 13.33° skip tooth method. Each pin position would be relevant to a specific tooth on the cam gear, of course.

Thanks for bring that up Panic. I know there is a picture of a custom Jesel belt drive set up in the Santucci book. Of course Jesel doesn't make anything like that or at least they don't have it listed. But it was combined with what looked like a 2 piece cover but they left the outer exposed to see the cam gear.

Donohue - As I mentioned in my above post, Cloyes has already discontinued the 8-1016 and 8-1018 gear sets. It's a shame how many parts are slowly but surely being discontinued.

I looked at this recently and decided there is no easy way to modify the stock parts. The center web on the cam gear has a wave in it for rigidity. This means any modification such as cutting up two gears and fixing them back together with a plate won't do it because there isn't enough material left to work with. If the center web was flat then I think it would be fairly easy.

To retard my timing 4 degrees I cut a new keyway offset 178 (or 182 depending on how you look at it) degrees from the original and remarked the timing dot. Worked great but as pointed out the keyway itself is the easy part of the job compared to pulling the cam and shrinking fitting the gear.

panic:"It's the same 13.33° for both (720° ÷ 54 teeth = 360 ÷ 27 teeth) because of the cam turning 1/2 speed with twice as many teeth. I'm sure this is a good compromise of maximum error vs. smaller teeth (weaker) but it makes corrections by skipping a tooth an "extreme only method"."

Well duh, Two meshed gears with a 2 to 1 ratio. Dopy me!
The three slot sets still turn up on eBay from time to time as do the straight cut gear sets. It might be easier to make the crank gear adjustable with a flanged sleeve though it would be much harder to access.

Don't feel bad, I stared at the parts (Harley-Davidson flathead 4-cam set) for an hour before it dawned on me!

Here's one of the cam gears with a substantial center web (look at the thickness of the holes).


A steel disc (very short cylinder) with the OD to match the (cleaned up) web diameter, thickness just below the web depression (to sit flush), and ID to match the (cleaned up) hub OD can't be that difficult? You may have to cut up 2 gears to make the hub and tooth ring a slip fit (unless EDM can do that?).

I still wish one of these was available for these engines.
http://www.jesel.com/valvetrain/images/BeltDrive_Header.jpg

Then you would need a custom ground reverse rotating cam.

I know of several that have been made for the 250/292's and a couple of 4 cylinders. They are a thousand bucks. Plus the added cost of a custom cam as FTF has said. So probably zero demand except for the all out race engine build.

Oh well

The OHC Pontiac 6 cylinder guys are doing that with their cam gears and making an adjustable cam gear like the red one shown above.

Never mind

Anybody got experience with the Enginetech 2528S timing sets?? If the quality is good, this unit would lend itself better to machining a hub and flange and adapting the gear portion to it. The web portion is flat and it could be machined and drilled to attach to a flange.

To be honest, it would be much easier to just broach additional keyways in the crank gear of either a Cloyes or Enginetech gear set. Sealed Power also makes them as well. Several 8-1016 and 8-1018 adjustable gear sets are on eBay right now as we speak, so there is still some inventory out there. I broach keyways for crank snout drilling fixtures i've made before, and have everything to do it with. So I could just buy a bunch of those timing sets and resell them at a modest upcharge for providing the service if needed.

I would also exhaust all efforts to locate the adjustable Cloyes sets thru Rock Auto, NAPA, Advance and Auto Zone before giving up on those options entirely. They can search each of their respective databases nationwide to see if any are available in some of their warehouses or stores.

Is the straight cut gear set better or worse than the angle cut?

Straight cut will be louder. Don't know if that makes them better or worse. Most racers use the aluminum gear set which is not straight cut if that helps answer your question.

From the info in the Santucci book, they list 3 different gear pitches. The first is 20° which is on the first upgrade, 14° which is on the first adjustable and then 0° which of course is the straight cut iron gear. My engine builder said the straight cut would be the strongest.

Scott, who has made the sets that you've seen? Were those Jesel too or someone else? Do you think it would be feasible/possible to cut extra keyways in the adjustable sets for 2° advanced and retarded adjustments? I think what's in those now is just 4°.

Apparently the link doesn't work anymore and I can't edit it.

http://cloyes.mycarparts.net/products/Cloyes-2528S?product_application_id=13419502520

Why would the cam need to be reverse rotation?

Gears: turn opposite directions
Belt or chain: turn the same direction

The belt drives were Jesel. I saw the first one back in the late 80's. Most builders agree that advancing the cam as little as 2 degrees will be of little benefit, so that's why most timing sets, even on V8's have 4 degree keways in them.

And then there is always this option.
HERE!

CNC-Dude, I was thinking the same thing,
http://www.rm-competicion.com.ar/principal.htm

I had forgotten about them also Rich until the light bulb went off. We need to start looking and thinking outside the box, because there are much larger inline product markets outside the US than we realize. Many of these predominately inline countries outside the US have all the resources within their own countries and do not need to come to US companies for their inline needs.

If you were to add up all the combined US motorsports racing groups we have here from even the most entry level of street and racing genres such as dirt track, drag racing, offshore boat, asphalt oval track, karting, motorcycle, Bonneville, etc and any other form of racing we do here and indulge in. And add them all together, then multiply it by 3 or 4 times, that's how large the inline Chevy and Ford performance market is just in Brazil alone. If you take that same total of US racing groups I mentioned above and get a total of the Chevy and Ford inline performance market from that, it probably wouldn't even be a full 1% of that total group. That's why more and more US companies are dropping inline oriented products from their catalogs and product lines.

To clarify juicetone's comment:

The 14.5 and 20 degree angles refer to the pressure angle of the gear teeth. This is the shape of the teeth. 20 degree may be marginally stronger than 14.5 degree but in my opinion the cam gears are plenty robust either way.

The zero degree refers to the helix angle of the teeth or sometimes called straight cut or spur gears. Spur gears should be stronger than helical gears but again, I don't think strength of this gearset is in question. Helical gears will exhibit axial thrust and will be quieter compared to spur gears.

The noise isn't an issue since I'm running open header and will be running an open exhaust out of the turbo when I finish the overhaul.

We need to find a translator and perhaps an importer!! Anybody here speak Brazilian Portugese?? If my calculations are correct, that unit runs about $1,921.00!

Those are in Argentina.
Here is the exchange rate.
6,285 ARS =310.945USD

Now get to buying. Always buy more than 1, sell the extra.

Thanks, Tom!! My mistake!! $310.00 U.S. dollars ain't too bad!!! Wonder what the import fee and shipping would be??

TLowe,
If you make it to PRI this year, talk to the folks at Saenz connecting Rods. Several years ago when I was there ,we talked to them and they make Rods for the Chevy 250 and the ford 200. We got to talking about parts for the inline sixes and I got buisness cards from them and met some of their other parts people. They had billet cranks guaranteed to 10,000 rpm, headers lightweight clutches etc.I will try to find those again.

Panic: thanks, I don't know why I didn't think of that. I knew that but just didn't think of it.

Thanks Scott. I wondered if there were some other options. And I've said this before about thinking outside the box. It's just going to take doing a little something different to get a little different results.

Stroker, I figured the 20° would be the weakest it being a step up from the fiber gear and on the opposite end of the straight notably being the strongest.

Thanks for all the replies gentlemen!

14.5 versus 20 refers to pressure angle:

https://www.quora.com/What-if-we-increase-the-pressure-angle-in-gear

14.5 used to be very common. Current practice for most gearing is 20 degree pressure angle.

Zero refers to helix angle:

https://en.wikipedia.org/wiki/Helix_angle

Zero helix angle means a straight cut or spur gear.

I would run 20 degree pressure angle helical gearing if I had a choice. Smooth running and quiet while being plenty strong for the application.

I'm planning on running the straight cut gears to reduce thrust on the cam retainer.

I'm ALSO planning on using the ATI damper/harmonic balancer!! I used them on my big block drag cars with confidence. When the SFI rules began calling for them, we started with the old Moroso balancer and lost a couple of crankshafts.

Jim Beatey, the founder of ATI sent us one of his balancers to try and the dyno showed a measurable gain in HP. The vibration was eliminated and harmonics almost disappeared completely, even on the 454" based engines!!

We tried Fliudamper and the TCI clutch style one as well. Went back to ATI and stayed! GM started using them later, as did several other manufacturers.

If I decide the next build, (if there is a next build) merits one, I'll be in the market for one of those Joseph timing gear sets.

Blackwater: What's the helical gearing thrust failure mode you are trying to avoid? I don't doubt you, rather would like to learn. Does it wear out the backside of the cam gear? Wear the thrust plate itself? Are you running an oil pump driven off the cam?

My mild engines have never shown any sort of problem with the stock cam drive design but maybe racing is different.

Your damper experience was it with v8 or was it with inline six?

Usually, the thrust sends the camshaft deeper into the block. I'm not sure about the inliners as I've never paid any attention to the stockers I've run or worked on.

Yes! My oil pump will run off of the camshaft using the same gear as the distributor. Again, not sure about the induced thrust from this. I'll know before I'm finished assembling this little guy.

My concern with the thrust is really low. I really wanted to know about the strength of the iron gear and the difference in the straight cut and the helical gear teeth. My other concern, the thrust issue, was just as related to the change in timing if the camshaft moved back and forth on acceleration and deceleration. We used a cam button on our V8s to prevent the camshaft from traveling back and forth.

I mentioned the ATI damper because of comments on another thread about harmonic vibrations as related to the four cylinders. Some of the Iron Duke cranks have fewer counter weights and most are much smaller and builders in the past have mentioned the harmonic vibration issue. This particular design, (the ATI damper) is made just for those problems and is "tunable" to help relieve and eliminate harmonics.

MOST of my experience is with V8s in this area. Ford, Chevy/GM, Chrysler race engines ALL benefited from the use of the ATI damper. I HAVE seen several used on inline 6s and even ODD FIRE V6s with no reports of problems and they are inherently safer in high performance applications.

Sometimes a better damper finds & fixes a momentary valve spring surge that was actually inherited from the harmonics.

Stroker, I know you guys know more about this than I but I just don't see how a higher pitch (20° in this case) is stronger than something with a straight cut gear? Is it because it has more tooth contact?

Blackwater, thanks for the info on the balancer. Where will you source the ATI balancer? Thanks.

Juice:

I think you are confusing three different gear geometry terms. Pressure angle, helix angle, and pitch are different and independent characteristics.

First, pressure angle refers to the shape of the involute curve which defines the tooth geometry. 20 degree is most common, 14.5 is old school. Pressure angle can be anything for custom designs but is standardized to 20 degrees for ease of manufacture, inspection, etc.

Helix angle refers to the twist of the teeth. It's probably about 30 degrees for stock inline gears.

Pitch refers to the size of the teeth. It is number of teeth per diameter or diameter per number of teeth if metric. I would have to look it up to be sure.

Does that help?

Blackwater: Inline thrust plate clearance is about .004 inch for a stock setup. This is all the cam movement allowed. You can easily alter this figure if desired. Oil pump will continuously draw the cam rearward so I'm not sure how much effect on timing you might see.

Thanks for that, panic. I was always a little puzzled by dramatic power loss, won't rev, etc blamed on harmonics. Harmonics exciting valve springs is a legitimate explanation.

Juicetone, I bought a nice used one for my big small block project, (another story) at a swap meet a few weeks ago for $100.00. As long as the unit isn't damaged, ATI will "rebuild" it for $75.00 plus shipping. For this project, (my 154" 4 banger) I'll probably buy a new one from ATI or one of the catalog speed shops.

Strokersix, thanks for the info! I doubt that one could take out much play at .004". Below that, you'd likely run into lubrication problems. I'm thinking the only advantage to running a straight cut gear set would be to reduce the possibility of wear on the cam retainer and lower friction in the meshing of the gears. The other advantage of the strait cut gears is, I have a set already.

Sealed Power aluminum Cam gear # 221-2526 54 teeth, Helix degrees 23, Helix minutes 25 Steel crank gear #221-2537 27 teeth, Helix degrees 23 Helix minutes 17. These are from the gear info I posted a while back.

Isky had a problem with a engine way back, had a big power drop at a specific RPM and killed MPH, but didn't show up on the dyno.
The Spintron found it: a harmonic at a speed in between the increments Isky used. He tested every 500 RPM, viz. 5,000, 5,5000, 6,000, this was at 5,200 RPM and not tested under load.
The Spintron showed the valve springs hopping up and down, on & off the spring seats like a sparrow in a bird bath.
Better damper fixed it.

Thanks Stroker. Pitch is definitely not what I was referring to then. I figured that had to do with the angle. I've never heard of pressure angle before this.

Blackwater, thanks. I would really like to use a good balancer on this build. Although I haven't looked I thought they may be hard to find.

I bought a Cloyes 8-1016. I'm not sure which pressure angle it is though.

Juice!! I've seen the damper for a small block chevy used. The crank snout is the same diameter. The ATI is available with a poly-groove pulley built into the outer shell as well as other options. They offer mandrels to run toothed, (blower drive) pulleys as well.

Panic, I'd like to see that video of Isky's harmonic demonstration!! I remember Smokey Yunick's demo with the electrically driven engine assembly, (basically a V8 compressor) and some of the research he developed.

As many of you know, I'm working on an old Chevy II engine for a rat rod project. I had the engine combination mostly worked out and then this complete '79 Buick turbo package stumbled into the picture, (I'm a sucker for weird stuff) trying to confuse the issue.

My engine package is built around a 9.5 to 1 compression ratio with turbo/nitrous capable forged pistons, six inch H-beam rods, a 181 crankshaft set up to provide a .400" longer stroke, a ported head with larger stainless valves, better springs, retainers, and keepers, and a performance oriented, (roller if I can find one) camshaft.

This turbo is capable of up to 12 lbs. of boost which will be excessive on pump gas. I can adjust the boost down considerably to reach a safe cylinder pressure. This isn't exactly what I'd like to do.

I'm wondering how much boost I could run and if the performance could be improved by setting this up to run E85. I have all steel fuel lines. The electric fuel pump is alcohol friendly. I can rebuild either carburetor that I have to run on alcohol or blended fuel.

This is a very simple little car with NO electronics used. Those first Regals had little if any computerized spark or fuel control and I'd like to keep it that way.

This one needs to be CAVEMAN friendly!!

My Jeep truck project has ALL the bells and whistles with electronic fuel injection, computer controlled automatic transmission, and even ABS brakes. I'm keeping the two of them separated!!

Big improvement not only in max boost, but how (excessively) rich and how much spark it will stand for anti-knock.
Someone I know with a serious Supra engine has about 20% more power on E85 than pump gas at 30 psi.

Looks like I might be in for a few tuning lessons!! Never ran a blended setup. I've run straight methanol and even some nitro, but none of them with a turbo.

Like the little robot in "Short Circuit"!! "NEED INPUT!!!"

The gearset is in. I still don't know what pressure angle it's on though. I can get the part numbers on the individual gears and also a tooth count if anyone is curious.

Post a photo of the gearset looking straight at it. It's most likely 20 degrees pressure angle. There is a visible difference between 14.5 and 20 degree pressure angle especially on the crank gear. 20 will be a fatter tooth with a pointy tip.

As long as you have a matched set it doesn't matter.

The number on the cam gear is 2524 and the crank gear 2501A.

https://s26.postimg.org/rruzt0hy1/I6_Gearset.jpg

https://s26.postimg.org/gfieb8oop/I6_Crankgear.jpg

Interesting. That looks like 14.5 deg pressure angle.

Pretty sure I have a set of each. I will take a look to compare.

The actual octane rating on E-85 at a gas station is all over the place. It differs among suppliers and batches no matter what the pump says.

The authority dictating the actual percentage of ethanol in the pump E85 is the ethanol manufacturer (who is subsidized by taxpayers): ADM, a/k/a Archer-Daniels-Midland, who pretty much owns Iowa and the corn business.
Corn-derived alcohol is that rare substance that requires more energy (and money) to produce it that it liberates when burned (and sold).

Follow-up: Juice, I found two crank gears today. One was marked '64 292 and is salvaged from an engine I tore down long ago. It looks like yours for gear tooth shape. The other one I have has fatter and pointy teeth origin unknown but guessing '70s vintage 250. I saved the early parts because I felt them to be useable parts.

I wouldn't hesitate to use yours.

Thanks Stroker. We lent our Santucci book out so I don't have those picture references with me. The things I said earlier in the thread about the book were from memory. I'll have to check again when I look at it. I do remember a picture they had all of the gears lined up in what seemed like weakest to strongest. In that picture the 20° was first, then the 14°, then the straight cut. That's why I figured the 20° was the weakest.

AFAIK it is not quite that sinister. The EPA is pretty transparent on these regs: federal gasonline regulations and specifically generic ‘pump gas’ cannot exceed E10 without proper labeling/warning else a service station is enabling misfueling: final rule on misfueling As such E15 is not ‘regular’ gas in today’s world.

As for the ethanol content in E85 - it is by definition a 'gasoline blend' of not less than 51% and no more than 85% ethanol. In practice service stations avoid delivering more than 83% ethanol: FuelFreedom.org which is for use in vehicles that can detect and utilize so called flexible fuels. The amount of ethanol varies by season, geography and availability of product: LiveScience

For me the most interesting thing about flex fuels is the BTU effect. Gasoline packs a much greater punch then ethanol. So the higher the percentage of gasoline in the blend the further your flex fuel vehicle will travel on a tank full . . .

So... we're not forced to buy ethanol at the pump, with the price subsidized (and made semi-competitive) by the general population's generous but involuntary contribution, at the behest if ADM?
How would I go about requiring 50 million people to buy my product, to the exclusion of my competitors, by Federal mandate?

Pay careful attention to the Iowa caucuses and primaries, in which the commercial item of greatest value to the businesses and citizens of the State is never discussed: corn subsidies.

Let's not get sidetracked on politics . . . The point of my post is that E85 cannot be expected to produce consistent octane. It is designed for vehicles with octane sensors. This makes E85 an iffy choice for a vintage high compression engine.

Why not save time, and just tell me I'm wrong?

Because you're not wrong. The quality of your posts and the content of the Victory Tech Papers are in evidence.

Well, back to gear sets. Thanks to all that have contributed.

Stroker, did you think it still may be the 14.5° pressure angle instead of the 20°?

I guess I'm asking so many questions on this because this gear set has to turn a roller cam pushing valve springs at 140#'s seat pressure and 350#'s open. I don't really think there will be an issue, I just wanted to make sure.

We never could keep teeth on the gears when we ran the steel sets, so we swapped to the aluminum cam gear set and rarely have problems.

Thanks Scott. I'm figuring this is the toughest set next to the straight cut iron cam gear set.

I got my straight cut gear set a couple of weeks ago!

Scott!! Should I worry about the durability?

My crankshaft came home today. 3.650" stroke, .010 under on the mains, snout drilled and tapped for retainer bolt.

I'm still looking for a mild street roller for this build.

Looks like the 14.5 pressure angle to me.

Strength of gear teeth is calculated using the Lewis factor. https://www.engineersedge.com/gears/lewis-factor.htm Basically a cantilever beam calculation. A fatter tooth will be stronger. 20 degree pressure angle gives a fatter tooth compared to 14.5.
20 degree will also have greater force pushing the gears apart which is not an issue in this case.

I think you'll be fine. Our issues were a combination of several factors that you might only encounter in the most extreme racing conditions we subjected these engines to.

Curious about straight cut timing gears . . . how does the cam thrust into proper position without the helix? I would think that it would tend to oscillate back and forth . . .