Proper cruising RPM.

[wythac]

A few other notes:

I have used the same motor in both my buggy (shorter R&P and gears with oversize tires) and a rather heavy 68 Baywindow Camper (with stock diameter tires and gearing) and the oil temps in both applications were/are pretty close, 10-15F cooler in the buggy despite using a slightly hotter cam in that application.

If the fan in your car is suffering a cavitation issue due to a negative pressure you would have a noticeable decrease in power coinciding with the sudden increase in temps. Not to mention that you would hear it too...

Dave and Brad are right but it seems you want to find more confirmation before you make any changes. Try the fan belt thing. Find a buddy with some smaller tire/wheel set ups that you can take a test drive with on your car. Let us know what you find.

[SBD]

[VOLKSWAGNUT]

All this good pertinent information... and keyboard diagnosis..... lets all just hope the oil temperature gauge and sending unit are accurate..




.
_________________
aka Ken {o\!/o}
Its your vehicle- stop askin' for approval-do what YOU like for cryin' out loud
Better to roll em' how you want and wear em' out-than lettin' em' rot out
Its about the going not the showing
Rebuilt to drive not decorate
WANTED: Local Eatin' Joints, Triple D for TheSamba contributions here http://www.thesamba.com/vw/forum/viewtopic.php?t=570510
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Usually and often edited

[Skulptorchaz]

The tire swap will be tough to come by. I don't have any and I'll have to do some checking to see if friends might. That will be tough.
Swapping wheels could also possibly be a waste of time, IF I could find out what the gears are in this trany. Cast #'s 11 113.301.103 / serial #'s 4851515 (no letters) I looked thru SEVERAL posts and sites but can't find it. I do believe it is a '62 as that is what the pan is. But that is just a guess.
This is the trany i had in it last year when I wrote the other post that NUT keeps alluding to. If this trany has a lower gear ratio, and it is still doing virtually the same thing, tire swap doesn't seem to be worth the time. So yeah, I have tried something, including timing and plugs.

Here is a pic of the dog house. Not sure what "Hoover bit" is tho. (??)

Shroud is the exact one that came on the engine. I stripped the 68K (mileage) Ghia myself. (The "rust belt" done the Ghia in.) I just smoothed it and powdered it. I learned from you guys that stock tin is best.

I will look into the oil pressure thing.

I'm not "stuck" on the aerodynamics thing. I was just stating how and when it heated up. It seems very cut and dried at 60+mph. Something "physical" seems to come into play then.

The belt is about as short as I can get. I'm not sure that that would make such a significant difference at 60+ mph but.....I don't know and why I am asking.

As far as the engine internals, besides the cam and 1915 kit, they are stock heads (cut) and I am in the process of putting 2-1 rockers on it. I want better heads but they will need to wait awhile before my money tree blooms again.
NUT, yes I am willing to do the diagnosis. I built the thing from basically scrap. (see pix) Please don't go there. I am humbly asking and I appreciate ALL the help.

I can not absolutely verify the Gauge accuracy. But, they are only about 6 months old. I almost have to assume.

In summary, I guess if the trany numbers show a lower geared trany, that "should" take the gearing theory out of play. (?????)
Next thing I guess is the oil pressure. Bad thing is, that will have to wait as I am out of time before I drag it (4 down as you guys recommended) up to Silver Lake Dunes next weekend. (A dune buggy NEEDS to be on the dunes at least once in it's life!! ) But, it will be OK as long as I keep it under 60 for longer drives around the area.

Thank you all again for all the help!! I DO appreciate it!!
Chaz

[VOLKSWAGNUT]

[Skulptorchaz]

I assure you, I am not asking just to be asking, and, not "doing" what you guys suggest.

[Dr OnHolliday]

Your problem is "aerodynamic", but not as you've been thinking about it.

To go X mph, the engine power must overcome aerodynamic drag and rolling drag. Rolling drag is about constant....

The aero drag for a particular car at 65 mph is 17% more than the same car at 60 mph [(65x65)/(60x60)].

Your fan speed at 60 mph is just enough to cool the car....
_________________
1965 Type 1 sunroof Baja / about 70k miles on self-rebuilt '74 1600 and counting / SP heads and aftermarket valve keepers / non-doghouse shroud with external cooler and filter / 1.5 qt extended sump / Weber 32/36 DFAV progressive carb / 009 dist with Pertronix / 1.25 ratio rockers and ball adjusters / 1.5" stainless steel J-pipes and carbon steel baja exhaust

[SBD]

You don't need to order the foam. Just get some from the hardware store. Nothing special, but having it should make a BIG difference. What about the Hoover Bit?
_________________
"Just $99 down and $64 a month for 36 months buys you a brand new Volkswagen Beetle!"

[VOLKSWAGNUT]

[vwracerdave]

You have 2 problems going on, and worrying about $2 worth of foam is not going to solve your problem.

60 MPH at 2400 RPM with 28" rear tires is way too tall of gearing/tire size. Normal highway cruising for a VW is 3200-3600 RPM, and where the engine is set up for it's best cooling. You can cruise a VW at those RPM's for hours and hours and hours. You need to verify the RPM's and MPH's and be within these ranges for long highway speeds.

With the SCAT C45, you have way too big of a cam for stock valved heads, and the engine is struggling to breath. At 2400 RPM your cam has not even started to breath yet and you are way under the cam's power curve of 3500-6500 RPM's. Changing ratio rockers is not going to help you at all with performance or cooling.

You haven't mentioned anything about it but I'm guessing you are getting horrible MPG. You should be getting over 30 MPG.
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK

[Skulptorchaz]

Fine, I understand now how you are. Opposite of me. I don't give out blunt remarks unless the person deserves it.

OK, foam, no problem. Got that.
I have the "bit".
Those are the exact numbers on the trans. No more, no less. The pan is a '62 so I have reason to believe the trans is as well.
My friend who races VW's says he is familiar with the springs and by-passes so I can check that in the near future.
Is there another/better way that I can cool it? I know it won't be the "right way" it should be done but.....

I understand Dave. I will look to rectifying these but, unfortunately, it looks like I will need to live with my bad choices for (quite) awhile....unless there are (cheaper) short cuts.
I'm told the rockers would "help", not cure, and I would need them for the "good heads" anyway, so I am easing into to it - kinda like a payment plan.
Yeah, mileage isn't there, for sure. About 22 mpg last I checked. I'll check that out again. I'll also see what I can do to confirm all gauges. (not sure how but...)
OK, not to get into a big discussion here, but just for my understanding, last year I ran a swing with what looks to be a 4.35 gear. (assuming here as I am not sure, because I can't find my numbers on a chart) Now I have in an IRS with 3.88s and my buggy heats up just about the same. I did not have a tach last year but I can compare mph by traffic flow from my highway trips that it is pretty close. I guess maybe the gearing doesn't make enough difference to notice. Could the cam be the biggest culprit?? Especially in conjunction with the gearing??

Thanks again gents!!!

I need to check it out but, it looks like the VW run by St. Louis will be a "no-go" this year. Anybody know the date?? Thanks.

[didget69]

This is what I get for your calculations -

2600 rpm at 60mph with a AN trans (3.88 Final Drive) in 4th gear (0.93) & running 275/60-15 rear tires.

http://vexer.com/automotive-tools/speed-rpm-calculator

Fun tool for estimating tire size /gearing changes - Input the AN trans gear values at each gear shift position:

3.80 / 2.06 / 1.26 / 0.93
Final Drive: 3.875

Read more at http://www.volksworld.com/tech-guides/technical-in...3tRFMTj.99

- then use slider bars for tire size changes, add in 3.88 / 4.13 / 4.38 final drive numbers to see how final drive changes affect RPM / speed. Slide Throttle button to increase speed -

bryan
_________________
I never found the need to impress people with any mechanic certifications, trophies or track wins... unless it was for Mom to post on the refrigerator door.

[vwracerdave]

With a 50 year old transaxle it does not matter what the numbers are, it could have been rebuilt many years ago and anything inside could have been changed.

4851515 was built in May '62 and came with a 4.375 R&P and .89 - 4th gear.
113.301.103 is just the part number for the case and means nothing else.

Sorry didget69 but most of those Internet gearing charts are wrong. The AN code transaxles used in Ghia's came with a 3.875 R&P and .89 - 4th gear.

Skul, what jetting is in your carbs? venturie size, main, airs, idle, and emulsion tubes?
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK

[EVfun]

It is easy enough to just count the gearing by jacking up one rear tire and turning the motor with a wrench. Mark the tire and count the turns of the engine needed to get one turn of the tire. The final drive choices are 3.875, 4.125. or 4.375 (an aftermarket final drive is possible but quite rare.) First gear is 3.78 or 3.80, second gear is 2.06 from 1961 and newer (and older is a very different transaxle that won't bolt up easily.) Again, aftermarket gears are possible but very rare (at least very rare that it wouldn't be a "selling point" you heard about.) Having one tire on the ground and one off means it turns 2x the speed as determined by the gearing (that is the differential at work.) For example, if you have a 4.125 R&P and a 2.06 second gear then your total gear reduction in second is 8.50. Since the tire will turn at 2x the speed when only one can turn it will take 4.25 turns of the crank to get one turn at the tire. Once you figure out the final drive you can figure out all the gears.

I recommend about 3000 rpm at 60 mph for a Bug (plus or minus 150 rpm.) It won't be as much of an issue for a light beach buggy, plus or minus 400 rpm should be O.K. I'm not sure why all the fuss about doghouse cooling. My buggy started out with a real 36 horse fan shroud by swapping back to an inline cooler and I still never could get the oil more than about 100F over outside temperature. I ended up putting on a power pulley to warm it up more. A lightweight beach buggy (mine weighed in at 1100 lb.) is nothing like a stock Bug. Western Washington is nothing like the desert southwest so trying to run 125F over ambient was a good target.
_________________

[VOLKSWAGNUT]

I posted your ratio check procedure previously up top too..

[Skulptorchaz]

Dave, here is what I have on the carbs-
Duel EMPI 40's. Mains - 115, air - 200, idle - 52. Sorry, I can not speak to the venturi or emulsion tubes. Plugs run slightly black. (I always run my Harley a little rich for cooling too. I assume that is true for other air cools.) I think the carbs could/SHOULD have a bit better tuning for optimal performance but, I'd have to take it in for that.

I will do what I can to get max cool out of the oil cooler as I figure it can't hurt. I can also do some checking on gauges next time out. I have an IR and I'll be sure to check the mph, again, against a "new car". As for the tach, I may have my fathers old tach and dwell.(maybe)
But it seems the consensus is gearing and cam. Bummer. Bad choices. Like I mentioned earlier, If there are things that I can do to "help", I'm all about it as cam and tires are not in the budget. My next major purchase will be heads (probably over the winter). I hope that will benefit me as well. Maybe not in temps but at least in performance.

Thanks again Gents!!!!!!!!!

[vwracerdave]

Your jetting seems to be close or close enough that it's not more then one size off. Engines run hotter when they are rich.

What is your compression ratio? What octane fuel do you use?
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK

[Skulptorchaz]

Don't know compression "ratio". I have never figured it out and the company that built my engine (13 years ago) never said. But the compression is good (about 120). I'd "GUESS" about 8:1 or so with these heads. But that is only a guess.
I run the best fuel at the pump. 90, 92 preferably.
OK well, I would have thought VW's were the same in respect to Harley's (being air cooled) and I know Harley's run cooler when rich.

At some point, I want to take it in and get the carbs set up for max perf. I set them up to this point but I was just working with what little i know. I'm going to wait till I get the better heads.
Thanks.

[Skulptorchaz]

OK, here is a novel idea - I do not have but definitely want/need an oil filter. I have been looking at the different set ups - solid mount pump, remote, dog house - and was thinking about doing a filter/cooler combo. Thoughts?? I know I need the filter, at least I would feel better with it, and I could maybe hang a cooler along with it.
I haven't found one that is a solid mount (with the filter hanging off to the drivers side) that will fit inside my Tri-Mil 4into 1 header yet so I was thinking on hanging on a "remote". At that point, would it be feasible to hang a cooler as well??
I know it's not "fixing" the problem but is there any drawbacks?
Thanks!!

[VOLKSWAGNUT]