OK... with the tach properly switched to 8 Cyl. 2500 RPM The 50 MPH 2800 RPM @ 55 MPH 3200 RPM @ 60 MPH How are these numbers for the trip??
Listen to Dale and change the gear ratio or put in a overdrive ******. I would not push it past 2800-3000 rpm for a long period of time. Ratio or ****** and problem is solved.......
Thanks guys I'm just going to go for it, Ive always wanted to take a nice drive in a nice ride and actually go some type of distance. Ill take it about 55 part way and slow to 50 during the scenic areas, so that will be most of the trip at 50! Oh and one other thing... Sometimes (not always but most) I have a faint rubberish burn smell coming into the cab (no smoke just a faint smell) and I can NOT for the life of me figure it out... The belt looks fine and the tires aren't rubbing on anything, I have the clutch adjusted right and I don't think I have a brake hanging up...
One more thing... what is the average Oil Pressure?? Mine starts out very strong then drops to almost nothing (at idle) when its warm, and low when driving (20 or less)
The smell is most likely just the crank case venting nothing to worry about. As for the oil pressure its not uncommon for them to have low pressure at idle when warmed up but its more important what it has while driving. 20 might be a bit low. What oil are you using in it?
Less than 20 psi when driving? And this is on a "fresh" engine? If it were mine, it'd be going in the garage, not on a 145 mile trip. My stock '51 with 78k makes a constant 45.
I'm not sure what it was but I just drained it because it was quite black! It seemed a bit thin though... Ive noticed that it seems 40 weight is recommended by some? Is synthetic OK for Flatheads?? Also why would it have a rubber like smell?? It doesnt smell like oil though.
Right now I am using 15-50 Mobil-1 in my '51. I thought I'd try it, because I had lots of it left over when I quit racing my vintage dirt car (the pan on the hemi holds 14 qts with dual filters and an oil cooler). Any oil 50 weight or over has plenty of ZDDP. I have been running if for 2 years now, with one annual change, and it seems just fine. Plenty of oil pressure, and the old girl seems to leak less that it did before.
It is very true that the new interstates have affected the way the flathead behaves. I just drove my '36 roadster with a 51 Merc flathead to Louisville from Chattanooga Tn. About 350 miles each way. At 3:00pm on Thursday I was running 60-62 mph on hwy 31E. The weather was about 93 degrees and the engine was running 185 degrees on the two lane hwy. I got on to I-65 at Elizabethtown and it went to 203 degrees on the super slab. The air temp on the 8 lane hwy is much higher than it is on a 2 lane road. When I got off the interstate it went back to 185 degrees in 6 blocks of city traffic. BTW I am running T-5 with a 9 inch ford rear with 3.25 gears. The only thing this engine doesn't like is a super slab or a 4 mile 6% grade on a hot day. John L
An old fellow told me once that cruising rpms were dictated by stroke and were related to a % of the factory HP RPM. so for over square engines, those with strokes longer then the bore diameter 80 to 85 % of factory HP rpm. for square engines where bore and stroke dimesions are nearly the same, 85 to 90% and for under square engines who cares. Going with your ford motor that was rated at 3800 RPM, cruising at between 3080 and 3280 would be your sweet spot, Should be able to run all day there. Now go to one of those calculators on the web and plug in your final drive (usually 1 to 1 top gear) your tire diameter, and your rear end ratio and the rpm and that will give you an over the road speed. My car has a 4.11 rear and with 28.75 tall tires, mine runs 3200 at 62 mph. I have driven it on trips of over 800 miles and never had a problem, My peak hp rpm is 3600, so you have a 200 rpm cushion on mine. That gives both of us the ability to run it up to 4000 if we have the need or desire. But watch yoru oil pressure and temps and listen to what the engine is telling you. And like old people old iron likes regular breaks...
I think your Grandad had more fun taking 5 days each way! That sounds good to me. I've had my old 50 Ford 10 years now. I haven't ever driven it real far at one time but it has a nice "comfort" zone at around 50 or so that it feels like it could go at that speed forever.
There was no place to run 80 mph nor was the old caddy designed to do that. According to what I have been told (I wasn't there obviously) the half way point or close to it was Humbug Mountain on US 1. They would overnite there and lap the valves. When these old cars were new no one went very far very fast at least not by todays standards. They would run forever with the proper care and still will but some of the originals just take forever to get there. The old truck is a 45 mile per hour vehicle it is designed to be a 45 mile per hour vehicle and in original trim that is all it will ever be. This is not to say that there is anything wrong with that, sometimes we just need to slow down a bit and shake the cobwebs out.
This post is a good example of where a mistake than take you.The tach reading was way off,oh my god,she can't take this abuse,it's going to blow up.......A few questioned the RPM's,a mistake was made,now it's all ready for cruising at 55-60 mph....
Somewhere in your thread,you said you were going to sell it, If this is a fact I wouldn't start changing things. The only weak shot on a flathead is the water pumps. If the pumps are fresh,drive it..
Im driving it From Wenatchee WA to Arlington WA (145-ish miles) to trade it and just wanted to make sure It wasn't a bad decision. it stays nice and cool and has new internals so I would think I should be OK... I'm just going to enjoy the ride with my wife and get up early to beat the traffic so we can just take her slow. I'm changing the oil with full syn. 40 or maybe even 50 weight if I can find it. at least that is what I'm getting from most other threads... I said before that it has only 800 Miles but after draining the old oil Im thinking its more then that, it was BLACK BLACK and pretty thin also...
Don't know if you already got an answer, but don't switch to synthetic oil if you haven't been using it since the engine was built. I have been told that synthetic oil will find a way to leak more than regular oil.
Yeah I have heard that also, it leaks a little as it is but Im looking for that extra wear protection... even though its not going to be mine by tomarrow anyway.
As I said earlier, I have been RUNNING 15-50 Mobil-1 for the last 2 years. It works fine, and leaks less than the conventional 10-40 I ran before. This is in a car that ran conventional oil for 59 years and 77,000 miles. You now have been told both ways. Make up you own mind.
I put 20w-50 non syn. Now its off to bed and an early rise for a nice cruise. Thanks to everyone with the helpfull push.
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