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Boondocker · 06-07-2007, 09:01 AM

I was wondering if anyone knows what the upper safe operating range is for RPMs for the Ford 302 engine is. This would be good information for me to have while going up the side of some mountian out west this summer. I am expecting some slow-high RPM climbs and I would rather not toast the engine if I can avoid it. Before some one says it, yes a diesel would be better but I dont have one and I dont see that happening this year. The F-150 is what I am working with here so responses about the 302 would be much appreciated.

pmclemore · 06-07-2007, 10:56 AM

Rodney,

I think you will hear and feel what is the best speed for your rig, especially as you drive the 1500 or so miles before you get to the Rockies. You should probably consider not using the D (OD) shift position at all. Someone may have a precise number - say, 33 to 3500 (which may actually be a comfortable range, come to think of it.) You'll also be watching your heat gauge, if you have one, to monitor during the climb.

If you end up making a tough climb at a very low speed, watch out for overheating your tranny. When you get to the top and want to take in the view at an overlook, be sure not to shut down without running at higher idle for a few minutes to cool your tranny and other engine fluids.

Happy trails!

Pat

overlander63 · 06-07-2007, 12:16 PM

3500 would be about where I would consider max. The 5.8 in our F250 runs about 3000 @60mph, and seems comfortable there.

john hd · 06-07-2007, 05:49 PM

idle?

john

Road Ruler · 06-07-2007, 07:48 PM

Hi Rod... I have built up a number of 302's, back a few years ago. The highly modified AMC Pacer (avatar) also has a HO 302 in it that I installed myself.

In all the years of aggressively running a number of high HP 302's I have never damaged one. Synthetic oil would be a must since you are pushing it while towing. Also a good cooling system would be a benefit. I used to get custom rads made when I installed 302's in cars like Pintos etc.

You can run a basic, stock 302 to 4,500 plus RPM but I wouldn't hold them up there for long. Like previously said 3,500 to 4,000 should be safe for climbs if the hardware is in good condition.

ROBERTSUNRUS · 06-07-2007, 09:08 PM

Hi, a "good 302" can tach 5,500 to 6,000 RPM max, but as Road Ruler and other's have said, I would hold it in a lower gear at 3500 to 4000 RPM max; Or lower if it can handle it. [By the way, AMC used a "304" V-8] I think Road Ruler is saying he put a Ford 302 in his car.

Note; by "good 302" I mean a stock engine, a properly built 302 can tach much higher.

DFord79 · 06-07-2007, 09:26 PM

My father and also Myself both towed with 302 engines. Being a Ford fanatic I can tell you they are very, very good engines. Factory max RPM on a 302 is 5,200 to 6,000 rpm. depending on the specific 302. However your towing with a pickup with a 302. Pickup speck says 5,400 rpm for my old F-150. You don't need to turn it that hard to get all the torque tho. Keep it cool,,,keep good oil in it. Its a workhorse and will serve you well if taken care of. You don't need to rev it over 4 grand to get all the power out of it.

wingfoot321 · 06-07-2007, 11:08 PM

Rodney,

My old 302 carb version was 205hp but, the maximum torque came off at approx 2600rpm. I used to routinely run it all day at 10% over that number. No overdrive.

I don't know the newer fuel injected versions but, I would bet the torque curve hasn't changed 5%. For gas mileage, temperature, trans, etc. I think 3000 rpm would make sense to me.

Incidently, I now have a gmc 2500hd with the 300hp,410rear and the max torque curve is something like the same, 2600rpm and I ran the hills out west last year at 2800rpm. Anymore than that is just a waste of fuel. I was pulling 7000 lbs and your 24 footer will weigh less but, for overall performance, I think you will find similar comfort numbers to what I have mentioned.

I don't know what your literature says about overdrive with your weight. Ford used to have a statement on the back of the sunvisor as well as in the manual.

The folks are right. The 302 is one of the best engines ford ever built. They are almost bullet proof. I never pulled as heavy as your trailer with my 302 but, cooling did not used to be a problem if you had the automatic with the trans cooler. Their radiators were huge.

Boondocker · 06-08-2007, 07:53 AM

Quote:

Originally Posted by pmclemore

If you end up making a tough climb at a very low speed, watch out for overheating your tranny. When you get to the top and want to take in the view at an overlook, be sure not to shut down without running at higher idle for a few minutes to cool your tranny and other engine fluids.

What are we talking here? 5 min? 10?

Quote:

Originally Posted by overlander68

3500 would be about where I would consider max.

Thats about the number I have been comfortable with Terry, but I did have some doubts about that since I run 1800 not towing, and 22-2400 towing on the average. It is nice to hear that the long 3000 tows are probally OK.

Quote:

Originally Posted by Road Ruler

Synthetic oil would be a must since you are pushing it while towing. Also a good cooling system would be a benefit.

What kind would you recomend? Are there any considerations moving from regular oil to synthetic?

Quote:

Originally Posted by Road Ruler

You can run a basic, stock 302 to 4,500 plus RPM but I wouldn't hold them up there for long. Like previously said 3,500 to 4,000 should be safe for climbs if the hardware is in good condition.

The engine is in good condition, it is a Grooms rebiult that has been in the truck for about a year. I dont like pushing the RPMs up, but I have learned that I want 2 things heading into a climb: RPMs and some extra speed.

Quote:

Originally Posted by DFord79

You don't need to rev it over 4 grand to get all the power out of it.

From the noise I hear thats about all I have ever cared to push it. Sounds like just about everyone is buying the 3500-4000 range as workable.

Quote:

Originally Posted by wingfoot321

The folks are right. The 302 is one of the best engines ford ever built. They are almost bullet proof. I never pulled as heavy as your trailer with my 302 but, cooling did not used to be a problem if you had the automatic with the trans cooler. Their radiators were huge.

The truck has an extra large radiator which has been nice. I forgot to specify that the truck has a manual tansmission.

So, if I hear everyone right; I want synthetic motor oil, keep the RPMs under 4000 on the extended climbs, and cool off the rig at the top of the climb before shutting her down? Does anyone see a serrious problem with me towing with this setup?

pmclemore · 06-08-2007, 10:27 AM

That you have a manual tranny erases my concern about fluid overheating. The trouble when you stop after pulling a load is that the parts are very hot from the work they are doing, and if the engine is shut off the fluid will have to sit there next to the hot parts and cook. Idling for a minute or two lets the fluid cool the tranny and then is itself cooled as it circulates.

Haoleman · 06-08-2007, 04:58 PM

11,750 before crank failure or meltdown. this is full race though!!!

Road Ruler · 06-08-2007, 07:44 PM

For many years I have been using Castrol Syntec 10W30 in our V6 TV's. Never a problem. It lasts longer than dino oil and I change it every 7,500KLM's. Any popular brand should be fine. Our 23' Safari would weight the same as your 24'. I would bet the 302 will be fine.

nymphfishin · 06-08-2007, 08:29 PM

Quote:

Originally Posted by Gen Disarray

I was wondering if anyone knows what the upper safe operating range is for RPMs for the Ford 302 engine is. This would be good information for me to have while going up the side of some mountian out west this summer. I am expecting some slow-high RPM climbs and I would rather not toast the engine if I can avoid it. Before some one says it, yes a diesel would be better but I dont have one and I dont see that happening this year. The F-150 is what I am working with here so responses about the 302 would be much appreciated.

Rodney
The 302 is a great engine, I've had three p/u trucks with it... But I never pulled a AS with them either.
I'm sure that by the time you reach the Rockys this summer you will have an idea about wheather or not you want to tackle some of the steeper grades. If you are coming through Colorado, the CO State road map includes the elevations and grade percentages on most/all mtn passes. I70 west of Denver is a killer grade, uphill for about 50-60 miles and some is very steep. There are some alternative routes that will avoid some of steep grades and still get you to the same spots.
FYI
Don

For my travel photo slide show:
Picasa Web Albums - Don - MY TRAVEL PLACES

SilverToy · 06-08-2007, 11:00 PM

Hello all -

Lovin the thread, and all the replies...!

Wondering about 'those killer grades' that just ARE in some areas of the country. Sometimes, there really is NO way around the uphill/downhill sections. Ces't la vie!

The follwing question, however, does come to mind...

Is there an "Optimal" speed for MAX air through the rad/trans cooler?? ie - are the byways better for that optimal cooling or is 'highway speed' (or whatever you can muster) the best choice?

I had a killer run, UP!!! from Cottonwood into Flagstaff, that really strained the TV, and while I agonized (Is this grade done after THIS turn???) these thoughts run thru my brain....

I added an electric fan w/ manual switch so I can get additional directed cooling when at slower speeds, but still the question rattles around up there....

Todays vehicles are so 'task engineered' that adding a bigger rad is often physically not possible, so what other options exist?? Explored the bigger Trans cooler, but again SPACE was the X-factor....

Thanks everyone! Appreciate the thoughts, and time inputted by all...

Axel
SilverToy

Rodger with a D · 07-05-2007, 08:52 AM

Hola All

In yeater-year all the factories had an extra automatic transmission cooling radiator in front of the regular engine radiator if the vehicle ( car/ truck/ van ) had an factory towing package. If your vehicle did not have this OEM feature, you could pick up an transmission cooling unit to aid your vehicle from just about any place that sold vehicle parts. Or you can cruz the local pick & pull a few times to pick up one for about five dollars from an Ford OEM or any after-market unit on any vehicle ( new boxes cost more $$$ ).

Since the Ford 302 is an factory stroked 289, the 302 with the longer stroke will have a better towing ability due to the improved torque.

Please enjoy your trips and send an after-trip report later.

Rodger & Gabby
COS

nymphfishin · 07-05-2007, 09:57 AM

Axel

Another option is to remove the fan clutch, install direct drive fan with more blades. The down side of that is the fan runs all the time and uses some engine HP.

A radiator shop did that to a small V6 several years ago and it seemed to work, I quit having heating problems.
Don

Boondocker · 07-20-2007, 10:00 PM

Or the engine is. Today heading up to the Powder River Pass (outside of Buffalo WY) I climbed several miles of the climb and the engine started to over heat. I cooked off some coolant and opted to retreat to Buffalo for the night. I was running about 3K RPM in 2nd and 3rd gear. I wonder if I should have gone with a lower RPM rate. Any Ideas?

ROBERTSUNRUS · 07-20-2007, 11:21 PM

Quote:

Originally Posted by Gen Disarray

Or the engine is. Today heading up to the Powder River Pass (outside of Buffalo WY) I climbed several miles of the climb and the engine started to over heat. I cooked off some coolant and opted to retreat to Buffalo for the night. I was running about 3K RPM in 2nd and 3rd gear. I wonder if I should have gone with a lower RPM rate. Any Ideas?

Hi, No. Higher RPM means less lugging and faster fan speed. Look for partially clogged radiator. This means remove the radiator, have the tanks removed, and rods run through the core tubes. [Note: flushing does not work.]

Boondocker · 07-20-2007, 11:55 PM

Quote:

Originally Posted by ROBERTSUNRUS

Hi, No. Higher RPM means less lugging and faster fan speed. Look for partially clogged radiator. This means remove the radiator, have the tanks removed, and rods run through the core tubes. [Note: flushing does not work.]

So would frequent stops witht the engine running be a reasonable approach? I'm not sure I am in a position to pull a radiator at this point in the trip.....

ROBERTSUNRUS · 07-21-2007, 12:04 AM

Quote:

Originally Posted by Gen Disarray

So would frequent stops witht the engine running be a reasonable approach? I'm not sure I am in a position to pull a radiator at this point in the trip.....

Hi, Yes. I would not want to do this in the middle of a trip if at all possible, but hopefully you can fix it when back in town.