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Discussion Starter #1
I picked up a set of CMS stage 2 blower cams and wasn't sure if I should get the adjustable cam gears or the crank gears. I keep reading different opinions s. I would like to hear the forums opinions, pros and cons s if each. I would also like to get so.e recommendations on valve springs.
 

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I'm doing the timing on my build right now.

I like the TFS adjustable crank gears, they get you typically within 1 degree of where you want to be.

You can then use the slop in the keyway of the stock gears, basically rotating them one way or the other before tightening them, this gets you a little more than +/- 1/2 degree which is usually enough to get the timing dialed in. If not you can grind the keyway tab on the gear a little smaller, using something like a dremel or die grinder with a small carbide or diamond rotary tip.

The stock gears are really well made and are nicely hardened, I doubt the aftermarket gears are made as well.

The only rub on the TFS crank gears is they need to either be welded or pinned together once you get your setting because the factory crank key isn't full strength on the end close to the crank shoulder.

One thing I learned the hard way, some guys take a used lifter and take the spring out and use it as is or weld it and use it during the timing.

The extra slop from this approach gives you some error in your timing measurement, you need to use one of adjustable lifters (TFS/Summit sells a kit with one of these) and adjust it so you have zero lash on the rocker before making the measurements.

For getting your top dead center I like the Crane brass tool, Crane 99412-1. This will screw pretty far into the chamber, which helps on a 2v because of the spark plug being angled and at the side.

I would take the rockers in that cylinder (either 1 or 6) out though when using this stop as it sticks in far enough that a valve might hit it if the rockers are in.

Re your valve springs, what max boost and RPM are you planning to run?
 

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Discussion Starter #3
I will be running around 10-12lbs right now. However I will be installing a new forged Shortblock and will be pushing to 18lbs. I currently have stock pi heads but when I finish the Shortblock I will either add trickflow heads or a good set of ported pi heads. Not sure how high I will be able to rev.

---------- Post added at 12:43 AM ---------- Previous post was at 12:02 AM ----------

Ii couldn't find anything with a adjustable lifter. Do you have a look nk?
 

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ether or both will work just fine. u r not gonna pull the cam gears out of time with too much h.p if thats what u r worried about. i have seen 800 plus hp cars not move the cam timing
 

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This is the TFS kit that comes with an adjustable lifter, if you don't need the other stuff in the kit they also sell just the lifter.

http://www.summitracing.com/parts/tfs-90100

If you are keeping your boost in the 10 to 12 lb range you could run valve springs in the 100 lb seat pressure range.

If you bump up to 18 lbs I'd go for 125 lb springs.

MHS (Modular Head Shop) is a good place to get valve springs from, they sell good quality ones.
 

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Discussion Starter #6
Thanks Calboy!
 

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I'm doing the timing on my build right now.

I like the TFS adjustable crank gears, they get you typically within 1 degree of where you want to be.

You can then use the slop in the keyway of the stock gears, basically rotating them one way or the other before tightening them, this gets you a little more than +/- 1/2 degree which is usually enough to get the timing dialed in. If not you can grind the keyway tab on the gear a little smaller, using something like a dremel or die grinder with a small carbide or diamond rotary tip.

The stock gears are really well made and are nicely hardened, I doubt the aftermarket gears are made as well.

The only rub on the TFS crank gears is they need to either be welded or pinned together once you get your setting because the factory crank key isn't full strength on the end close to the crank shoulder.

One thing I learned the hard way, some guys take a used lifter and take the spring out and use it as is or weld it and use it during the timing.

The extra slop from this approach gives you some error in your timing measurement, you need to use one of adjustable lifters (TFS/Summit sells a kit with one of these) and adjust it so you have zero lash on the rocker before making the measurements.

For getting your top dead center I like the Crane brass tool, Crane 99412-1. This will screw pretty far into the chamber, which helps on a 2v because of the spark plug being angled and at the side.

I would take the rockers in that cylinder (either 1 or 6) out though when using this stop as it sticks in far enough that a valve might hit it if the rockers are in.

Re your valve springs, what max boost and RPM are you planning to run?
This is pretty much everything I did.

I want to say my lifter and piston stop were Comp cams though. I'd also note that the lifter was a solid lifter, not adjustable. Works just the same, but just an aluminum piece that prevents any movement during measurement.
 

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Discussion Starter #9
If you're interested I'll probably have a set of tfs crank gears for sale by the end of the weekend. No miles on them, just used for a mock up. Pm me if interested.
Sent you a pm.
 

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I went with cam gears this time around because I got sick of buy new crank gears every time I get new cams.
 

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Discussion Starter #11
I went with cam gears this time around because I got sick of buy new crank gears every time I get new cams.
Do you see any disadvantages to using cam gears? My cams will be in this engine until I pull it and replace it with my forged setup.
 

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I think there are pluses and minuses to the adjustable cam gears.

On the plus side its definitely quicker and easier and they can be reset for different cams down the line.

On the negative side they weigh more (probably not a big deal) and at least with the early versions there were some problems with them losing adjustment but I'm assuming that's been sorted out by now.

There are 2 adjustable sets I know about, the TFS ones and Cloyes also makes a set, I haven't used either so hopefully someone will chime in on which ones are better.

The TFS crank gears are simpler but the welding or pinning takes some extra effort.

I tried welding mine first but they are made out an alloy that doesn't weld so hot (at least with my so-so welding skills) and since the welds weren't great I pinned them also.

I used three 1/8" hardened pins, the gears do drill pretty well for the pins.

If you haven't done this timing before here's a pretty good video on the basic process:


Here's an example using TFS crank gears (he uses the Cloyes gears also $$$) TCCoA Forums

TFS really should supply some pins and instructions on how to use them with the gears.
 

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Discussion Starter #13
I think there are pluses and minuses to the adjustable cam gears.

On the plus side its definitely quicker and easier and they can be reset for different cams down the line.

On the negative side they weigh more (probably not a big deal) and at least with the early versions there were some problems with them losing adjustment but I'm assuming that's been sorted out by now.

There are 2 adjustable sets I know about, the TFS ones and Cloyes also makes a set, I haven't used either so hopefully someone will chime in on which ones are better.

The TFS crank gears are simpler but the welding or pinning takes some extra effort.

I tried welding mine first but they are made out an alloy that doesn't weld so hot (at least with my so-so welding skills) and since the welds weren't great I pinned them also.

I used three 1/8" hardened pins, the gears do drill pretty well for the pins.

If you haven't done this timing before here's a pretty good video on the basic process:

How to degree the cams on the Ford 4.6L 2V SOHC. - YouTube

Here's an example using TFS crank gears (he uses the Cloyes gears also $$$) TCCoA Forums

TFS really should supply some pins and instructions on how to use them with the gears.

This is my first build and everything I do is a learning process. I have to admit the cam install and Timi g is kind of intimidating. With all of the stuff I have done to the car I dread to see what bugs I have to work out.
 

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Price on cam gears is more expensive . Somebody else can chime in on this but I think the cam gears give more adjustability.
 

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Discussion Starter #15
I am still torn. I have watched videos and read articles and still can't decide.
 

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If you have a way to weld or pin the cranks gears I'd go that way but if that's going to be a big hassle I'd go with adjustable cam gears.

I think the only good way to pin the cranks gears is to at least tack weld them while they are on the crank hub first, then take them off and drill the holes for the pins.

A mig welder would be fine for that but if you don't have one then that's a deal killer on the crank gears.
 

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Discussion Starter #18
I can weld and pin the gears. Probably going to go that route.
 

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I used to use the tf gears. They were not pinned or welded. Never had a issue with them. Now I use the mmr adjustable cam gears without issue.
 

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I know guys have gotten away not welding or pinning the gears but the key in the crank isn't engaged in the crank under the back gear so under heavy load (high RPM, heavier springs) it can snap that part of the key off.
In the instructions that come with the gears TFS recommends welding or pinning them.

Its cheap insurance because if it does snap your engine is likely a goner.

I ended up using 1/8" OD 7/8" long hardened steel pins on my gears, this length ends up being just right. The gears drill pretty easily but you at least need a drill press.

If I hadn't welded them also I might have gone thicker on the pin size but since I had welds in 4 spots I figured three 1/8" pins spaced evenly would be enough, each pin has a shear strength of around 1300 lbs.

The reason I pinned them after welding them is the welds looked so-so, I used a tig but ended up with some surface cracking, I guess because of the alloy type used on the gears.

If I had gone with just tack welds I probably would have used 4 evenly spaced pins instead of 3.

I had to buy a box of 100 of these pins which I'll never use up so if anybody wants 4 pins PM me your mailing address and I'll send them to you in a letter envelope.
 
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