Walt's Model B spare engine

I love it, Never seem one of these before. I did see an engine with 5 cam bearings tho at a show.
 
Well I was at the gathering a few years back and a fellow gave a talk on modiying the A and had a block there where he added two cam bearings. I didn't think the spring pressure would be high enough to need this. Yes I knew the cam ran in the block. However I've never worked on any. But I love driving yours. Next time I come up there I'll hide your daughters lawn mower so I can steal it again.
 
Walt Dupont--Me. said:
I don't use a test stand to break in an engine. When I first start an engine, make sure you have good oil pressure, if it hitting all cyl, speed the engine up 1500-1800 rpm and let it sing 10-15 min. jass the throttle every now and then, keep an eye on the oil pressure and temp ( assume you have a radiator on this test stand ) NOW, you slow it down check timing, ajust carb so it idles .That should only take a couple of min. NOW, don't start it up every time a friend come over. NOW, the rings are not really broke in, the right thing to do put it in the car, take it out on a piece of road where you can peddle to the meddle up to 50-60, slack off back down to 30, peddle to the meddle to 50-60 back to 30, do that 10-12 times and drive it normal, the main thing is don't let a new engine set and idle for a long time. Most of you cain't imagine how many tractor engines and industrial engines I've built in over 60yr's. Do you think they went all went through this BS when they put these engines back in. How do you think all these old stock car engine myself and Old Ron ect got broke in. Put em on the track and wind the s-t out of em. I realize the word common since left the dictionary years ago, maybe we should invent another word for it. Walt
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Well said and how I have always believed it should be done
 
scooder said:
I've often thought that silly shape crank is a big power limiter on the four cylinder. To get power we need torque and the ability to maintain that torque at high rpm. That crank limits the rpm of those engines.
If you look at the little four cylinder Ford engines, the 10hp Prefect and Popular (Anglia) with 1172cc (71ci) the guys raving them in the 1172 formula were getting high 70's to low 80's in brake horse power at 8500 rpm. This made the little home built race cars attain speeds upto 130mph on the straight at Silverstone circuit. These were flathead engines! The rpm limit was the camshaft, by all accounts the rear cam bearing would exit the bottom of the pan at 8600-8700 rpm.
Be amazing to get one of these big fours to that level, wounder how much power could be got if you scaled up the modifications on the little fours to the big fours? The saying "no replacement for displacement" does make me smile in this case, 130mph! And the car wasn't built for outright top speed, it had to accelerate and corner and last longer than a return run of seven or so miles on straight Line salt. The guys made there own heads, some from melted down milk bottle tops for the aluminium, some ground there own cams, by hand, on an off hand grinder (bench grinder) some of these guys ran radius lifter re entry camshaft profiles ground on billets, using Austin seven radius lifters and profiles.
The A and B engines are around three times as big, with the same porting layout. Now you have a good design crank for yours, and a monkey motion head.
I'm just letting you know what I expect from you and that engine!




Only kidding, on the expectations.




Maybe,



Might be serious,




Have fun
Martin.
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Ha Ha ! I like a challenge! this is my third attempt with an A/B block to get serious power, and its taken 2 broken cranks thus far. The last motor made just under 180 bhp at 4500 rpm on the dyno, which isn't a lot for an ohv 3.3 litre engine. So I will be very disappointed if we cant get well over 200 brake with this one.

As you say Martin, its all about revs, and the limit seems to be crank and cam. So now I have a great cam, and have had one ground from a blank to my own design, instaed of putting a grind on a standard cam.

I think the crank was breaking because of a torsional vibration, so have had to come up with a damper. I have used a "Rattler", but am not at all sure its the right one for the job.

The pistons are Ross, who are great people to deal with. The crank and rods are Arrow Engineering, a top firm local to here.
 
Walt Dupont--Me. said:
Hey Ron. The early 28 had 5 cam bearing. BTW, model A-B don't have cam bearings, the cam runs right in the block, just like the 8N -9N tractors.
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Hi Walt
In my first block I fed oil to the cam bearings under pressure. Now I have changed the way the oil gets to the main bearings and the cam wont get oil under pressure. I think this could be a problem, and will have to re do it.
Tom
 
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