Rebuilt Flathead Problems.

I checked a stock spring at recommended installed height and compressed .030 (cam lift) witht the following results: 39lb at 1.89" and 80lb at 1.59". Then 60lb at 1.675 and 110 lb at 1.375. (no coil bind). More pressure than needed for a stock cam.
 
flatjack9 said:
I checked a stock spring at recommended installed height and compressed .030 (cam lift) witht the following results: 39lb at 1.89" and 80lb at 1.59". Then 60lb at 1.675 and 110 lb at 1.375. (no coil bind). More pressure than needed for a stock cam.
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I wouldn't consider that more pressure than needed for a stock cam, 39lbs at 1.89 is the stock spec.
 
I was referring to the 60 lb at 1.675 where he originally had the spring set. I thought that was pretty clear, but I guess not.
 
Wasn't clear to me, LOL. Thanks for the clarification. What was the free height of the spring you were checking?
 
FYI I have a cam that Schnieder cams did a regrind on for me many years ago. Here are the specs that came with it. Interestingly enough I had lost the original cam card and emailed them one Sat. night at about 11PM to see if I could get the info again. I got an email back from Jerry in 10 minutes asking for the number stamped on the end of the cam and informing me the cam was done in 2001! How is that for customer service!!

.355 lift
260-F
260- Duration
226@.050"
112 Lobe Center

Valve Lash
Intake - .010
Exhaust - .012
 
That cam should be great for this engine. What spring pressure did you end up with - on the seat? Depending on how high you are planning on revving the thing, I'd go somewhere around 60 lbs on the seat.
 
Kahuna thanks! Hot damn I have a part that I don't need to think about replacing!

Bored&Stroked. I haven't gotten to the end of my valve spring fiasco yet. I had published the list of numbers I got when I used the second groove on the chevy valve for the valve keeper and then checked the installed height. (See post 192 on previous page.) I was told by a lot of folks I had to use the first groove on the valve?? So I remeasured the installed height using the first groove for the keeper and it went from 1.675" with about 60 lbs to 1.905" and about 25 lbs. So I just went and dug around in my stash and found some other longer springs. I am going to go through the same exercise again with the longer springs when I get back into the shop. I'm also awaiting spring retainers and guides from Gary in NY. I have a feeling I am going to have to shim some either way I go.

This is going to be just a nice street motor. Not ever going to be on a track or anything close to it?
 
So today while awaiting valve parts to show up I decided to get brave and drill the lifter bores to accommodate using something other than the Johnson style lifter adjustment tools. Happened to have an extra long drill type chuck and a 1/8" drill that just happens to fit it. Piece of cake really compared to some of the other crap I have been going through on this motor. Seeing as I have the pan off and could get at the lower end to make sure there are no random chips or debris where there shouldn't be I figured why not do it. Another of the things the builder was supposed to take care of that he didn't do. Still need to run some emery cloth down the bores to make sure there are no burrs. A couple pics.
 

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I recall that consensus here is to drill 3/16ths.

The johnsons are fairly stiff to crack and turn.

I feel more secure with a 3/16ths hole and the biggest allen key that will fit in.

I think an allen key that would fit thru a 1/8th hole would cause a bit of sweating at maybe breaking off.

Although , it is your call.
 
pooch I only had a 1/8" drill for that chuck so thats what they got. I'll see if I can round up a 3/16". The end of a 1/8" straight punch fits nicely in it but I wondered what would happen should you break the tip? You'd probably have to pull that valve assembly and get the lifter out and remove any broken part of the punch. So going to 3/16" won't hurt my feelings at all! Thanks.
 
Ok guys. Here is a small update as I am still trying to figure out what I will do about my valves. Everything looks pretty good on the lower end and the cam and crank are now in time so I am going to button up the lower end this week. Any tips on reinstalling the oil pan and timing cover so I don't have leaks are welcome!

A follow up on the crank gear timing thing. Where I guessed at and marked a timing mark on what was the back of the gear, when turned around it was as best as I can tell 1 tooth out of position from the actual timing mark on the other side. Not sure how it would run doing it by guessing the location from the crank keyway but I think it might have been close enough to fire.

Now to measure up all the valves, springs, keepers, and other associated hardware to see if I can put together a set that will do the job I need.
 
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Schneider makes a good cam, this one is similar to the Isky Max #1. If you've read JWL's book you'll see that will reduce the torque output if the engine at low RPM's. Increasing the displacement and compression will increase torque through the RPM range.I don't think #60 of valve spring is necessary, but it probably won't do any harm. A street engine spends 90% of it's life under 3000 rpm. I used #50/55 lbs on the seat and used the second grove in the Chevy valve many times with no problem. Most of the time a stock spring wit a .060' shim is all that's needed. Now with all this said, you can spend more money on improving this, but I don't think it's necessary. What hasn't been addressed is the guides? Have they been knurlled? the reason for this is the fact that a loos valve stem to guid clearance is where oil is sucked into the cylinder under hi Vacuum. Knurling prevents this, It also lubricates the valve stem. This is a better place to spend you money. Also piston to cylinder head clearance. Mill head for .045/.050" clearance. This improves throttle response and economy. probably the best bang for the buck. I don't like to spend allot of money on these engines unless it's necessary and most (not all) of my engines are still running. I was just informed that Dons Engine has passed the 40 K mark and Ron Horrell's 296 50K Just lov these flat motors.
 
Ron thanks for the additional info. My engine is bored out to 3 5/16" and it has the 4" crank and the Schneider cam and adjustable lifters. All new rings, bearings, cam bearings, and new oil pump. New timing gear, new crank gear. Drilled out for the 95% full flow oil filter I have new Offenhauser aluminum heads as well as a set of Mercury 8CM heads. I have both copper and regular head gaskets. I have a 3 deuce intake with rebuilt 97s for it but for start up I am just going to do the break in with a single 4 bbl carb.

My guides were just standard Speedway guides which I have sent them up to Gary in NY to have them bronze lined. Is this different than having them knurled?
 
Bronze lining the guides is better than Knurl ling them, if properly fitted to the valves. If Gary did them, not to worry. I just don't think it worth the money for a Flathead. The 8CM heads have a large combustion chamber, which gives low compression. Check the CC's of the heads for a proper CR ratio. Sounds like a nice build
 
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