51 merc needs a little speed up

[WestCoast]

if its a stock engine it does not get all its horse power till the engine turns 3600 rpm, so 2500 rpm wont hurt , what kills these flat heads is over heating, so keep your eyes on the temp gauge

[oldford2]

Originally Posted by oldsman41;1300296[B

]getting tired of the cussing and the one finger salutes im getting from the a holes im on the road with.[/B] im sure they think im doing 60 in a 70 mph zone just to peeve them off but the merc is stock motor and 3 speed od. 60 seems where it wants to be,about 2050 rpm. what i like to know from the gurus here is can i go to a different rear gear and not tear the clutch out of it when starting out in 1st.its got the 4.11 in it now. or am i baby it to much at the lower rpms. she seems very content at the 2050 rpm. tires are 235 75 15s thanks in advance.

Well, you don't mention where you are. What country/state? I think you are exaggerating how often this occurs and you must have good ears to hear the cussing over the flathead. I have a Mitchell in our 46 and can easily run at interstate speeds...but I don't. 1946 brakes and steering are not safe at 75. I generally stay around 60 and let the cars go by. Never got a finger but plenty of thumbs up. Calm down and enjoy the ride. JMO
John

[Mike51Merc]

Originally Posted by 19Fordy

Oldman41: Before you go searching for another ring and pinion do some calculations.
It may not be worth the trouble.
http://www.advanced-ev.com/Calculators/TireSize/
Also, here's a good article. If the Merc OD unit has a .7 ratio, then the final drive ratio for your 4:27 rear in overdrive would be 4.27 x .7 = 2.98. Why change?
http://www.hotrod.com/how-to/transmi...ner-overdrive/

19Fordy is right. If your final ratio is too tall, your engine won't be happy twisting that driveshaft at speed.

Now here's a question that hasn't been asked: Are you sure your OD is working?

[Ol' Ron]

I think some of youse guys should buy JWL"s book before you sttart giving advice. He gives Dozens of dyno results for stock and modified engines. And stock engine runs out of steam long before 3600 RPM. But the factory never read his book.

[38 coupe]

With the stock 4.27 axle and 0.7 overdrive I would not be afraid of running the engine up to get to go 75 mph. The condition and function of your brakes, suspension, and driver reaction time are however totally your discretion. I frequently run my 53 Ford sedan 70+ with confidence.

As others have said, are you sure the overdrive is working? If so you have no issues with engine revs. If not, your motor will be sounding busy (but may still be fine). I would not re-gear the rear axle. Lugging the engine will too tall a gear is much worse than spinning a few more rpm.

[oldsman41]

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sorry guys i was away for awhile had company. yeah the od is working fine and im probably a little paranoid about the engine running at a little higher rpm. just love this flatty and really dont want to hurt it. i guess i will just ignore the people that think im not going fast enough. and i do take the back roads whenever i can. i can do the speed limit on those pretty easy. i still get passed by everyone in a big hurry there too but what the heck. thanks every one i will keep all this info too, good to know people out there willing to help.

[outlaw]

Originally Posted by Alaska Jim

I have a '51 Merc. It has a 3sp w/ o/d and 4:27 rear gears. I cruise it at 65-70 all the time.

And I can attest to that! I've been in it at 105 before too! Bill

[Alaska Jim]

Yeah, It was fun, wasn't it? still had a bit left, not a lot but it was still pulling, but was running out of straight road. took it and the coupe to the O'rilley's car show in Palmer Sat. the coupe won 1st peoples choice and the managers choice. really surprised me.---Jim

[Talkwrench]

Sounds like they're just jealous..

[outlaw]

Their both very nice cars, but that Merc when it gets up to speed look out, and with the weight it's got a nice ride too! Bill

[41LjH]

Measure the height of your tire.
Then play around with the variables.

http://www.csgnetwork.com/multirpmcalc.html

[Ford46]

OldFord2 has the proper attitude, a 51 Mercury sports 61 year old technology (steering, brakes, etc.) trying to keep up with today's traffic is insane (actually most driver's today are insane). You cannot handle, or stop like they can, let them go around! JMHO LouB.

[oldford2]

Originally Posted by oldford2

Well, you don't mention where you are. What country/state? I think you are exaggerating how often this occurs and you must have good ears to hear the cussing over the flathead. I have a Mitchell in our 46 and can easily run at interstate speeds...but I don't. 1946 brakes and steering are not safe at 75. I generally stay around 60 and let the cars go by. Never got a finger but plenty of thumbs up. Calm down and enjoy the ride. JMO
John

One of my "buddies" told me that all the thumbs up are for my pretty bride of 56 years sitting next to me

[WestCoast]

ol"ron, kinda sharp with your reply, I know all about rpm and horse power and torque curves, what I was saying is he can turn the engine to 2500 rpm and his engine will be fine

[Mike51Merc]

Originally Posted by Ford46

OldFord2 has the proper attitude, a 51 Mercury sports 61 year old technology (steering, brakes, etc.) trying to keep up with today's traffic is insane (actually most driver's today are insane). You cannot handle, or stop like they can, let them go around! JMHO LouB.

So true. I drove my '51 on the Pocono Nascar track several times during Good Guys shows. Had my speedometer up in the nineties and she still had more to give. My confidence gave out before my engine did.

[Ford46]

I should have said a 51 mercury sports 65 year old technology....sorry.

[39topless]

getting the finger from people passing you in your old car gives you a sense of what the Amish must put up with in their horse draw wagons. I agree with the advice to just give'm back a thumbs up or the peace sign.