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Thank you all for the direction to buy the Muir Book on keeping my VW alive. Great reading and ideas. The first section to catch me was on shifting. I learned to drive a stick on a VW – did not drive it more than just the learning. Now with this one the book is saying that I should not need to use 4th gear unless I am going over about 60? And that doing so will overheat the engine. Guess that might show why the little I have been able to drive and have been driving in 4th at around 45 and up to about 55 the engine was very hot. I do not have a temp gauge just felt the heat. I guess my question for you Great Master Machnics is at what speeds do you shift? When going 45 or so, in 3rd, it sounds as if it wants 4th. Is this something I should get used to and trust the manual that the engine wants to run at higher rpm? Do I just use 4th if I make it out on expressway? As you can tell the Manual was written with me in mind….
I typically don’t shift into 4th gear until 45 – 50 mph when I’m out of a lot of traffic.
The major reason for running in 3rd gear at lower speeds(stop and go traffic for instance) is to keep the fan moving at a faster speed to push cooiling air around the cylinders. Also, and maybe in the book (haven’t read it in a while) many aftermarket folks sell what is termed a power pulley. It slows the rpm of the fan down allowing more power from the engine. This is great for racing VW engines where you will be turning high rpms and speeds but sucks on a street engine, again for the reason mentioned above. To keep your engine running cooler you have to keep the fan speed up. Also, every now and then it’s a good idea, when you shut the engine off, to check the fan inlet and see if there is any debris trapped up there.
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackI’m just learning too. First time I drove Bridget, with the PO riding shotgun, he’s all like, “you’ve got to rev it! it likes to be revved.” I didn’t wanna. I learned to drive a stick on a 1970 Camaro with a 350 and a 2 bbl. That motor ran out of wind at about 4200. It had plenty of grunt at 2000 though . . .
Anyway, these are nothing like that, right?
These want to stay in that 2500-4000 range, seems like, and B still pulls as well as she can up through about 4800. I shift Bridget into 4th at around 50 (unless I’m rolling down hill or planning to cruise steady at a lower speed), and she doesn’t seem to mind. If I’m doing 40-45 and the car’s already in 4th I find I have to downshift to do anything anyway, so she mostly stays in 3rd till then.
This car is a single port, single solex of indeterminate displacement–probably a 1500 by now at least, but she’s in a 1300 case.
Hope this helps.
I know. Everything Ed and Allen wrote sounds counter-intuitive, right?
That is probably because most of us are so used to water cooled engines. We all assume high RPMs mean more sparks and more combustion, all of which should mean MORE HEAT.
But…our lovely air-cooled VWs are cooled by the fan blowing air over and around the cylinders. The fan is spun by the same pulley that spins the generator.
Simply put, the higher the RPM, the faster the fan spins, and the more air it moves over those cylinders.
This is the same reason we have heard Mark (pinkmg) speaking out against freeway-flyer transmissions in recent days. Fourth gear in a VW is already an overdrive gear (about a .89 I think). Over the long haul, a longer fourth gear that slows the engine RPM at highway speeds will have a detrimental effect on the life of your engine!
My Duchess turns around 3,000 RPM at 60 mph.
In a stock Beetle this is no big deal as the engine is further from your ears and better insulated. In our replicas, the engine is uninsulated and is right there, a couple feet from your ears. 3,000 RPM sounds like the engine is gonna blow apart. But it’s normal! Enjoy the sounds!
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
This was a good topic. I felt the same way when I got my VW based TD. Ed and Allen are right about the 45-50 range before shifting into 4th.I had never owned a vw before, but friends that had, told me to keep the revs on it and explained why. I agree with what Paul said about the engine sounding like its gonna explode at 3 grand, but when we think about it the idle is set a around 850-900 rpm so 3000 rpm isnt that excesessive and I have come to enjoy that sound. When people ask me how my car is to drive I answer “1st is too low, 4th is to high, but 2nd and 3rd are a heck of a lot of fun!” Mike N Scarlett40765.7593287037
Paul…can’t figure where I posted against using Freeway Flyers. Using one in these little light cars, IMHO they are GREAT! The first Pink MG had one and I plan on using one in the very light Volksrod I am building.
A “Freeway Flyer” usually has a higher 4th gear and higher ratio ring and the pinion from Super Beetle transaxle. Some builders just use the higher Super Beetle ring and pinion (3.88:1?)
Faster/slower fan speed is directly related to engine RPM’s not MPH. The engine doesn’t know how fast it’s travelling down the road.
A power pulley and missing engine tin indeed does heat damage to a street VW. The power pulley messes up the fan speed to RPM ratio and the missing engine tin screws up the cooling air flow.
At any ambient temperature, RPM’s (friction & faster combustion cycles) makes the heat…more RPM more heat. More RPM, more fan speed. So, the engine gets the correct amount of cooling air no matter what the mph in theory.
Other mitigating factors are short-shifting, vehicle gross weight, etc…stuff that labors the engine. In fact, my experience is no higher temps using the Freeway Flyer in the first Pink MG…even when I short shifted it.
These little boxer’s don’t spin up like a water cooled V6 or V8. IMHO, 4,800 with a stock mill is pushing it. They are louder too because they are air-cooled, solid lifter and aluminum/magnesium alloy. No water jackets or hyraulic lifters to absorb the engine sound. Plus, as previously mentioned, nothing but a thin fiberglass firewall and we sit in the former back seat location.
Could be my bad memory Mark. Sorry for misquoting.
But I do have a question….
If VW built their cars for 3,000 rpm at 60mph, and a Freeway Flyer trans has the engine turning 2,500 at 60 mph, is the lower fan speed a problem?
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Learn something new every day. Always heard never bog down a VW motor. Now I know why. Thanks guys. Looks like I’m gonna be adjusting my driving habbits as well.
As for the noise. High RPM’s don’t bother you near as much when you have a pleasant exhaust note!
Really, I don’t spend much time above 4500. But I have revved her a bit higher once or twice, “pushing it,” as Mark says, just to see what’s what. There’s not a lot to be had up that way, but then again, she doesn’t drop off much either.
Paul, try to disconnect relating Fan Speed to MPH. It’s all about engine RPM to Fan Speed. Again, the engine has no idea how fast it’s going down the road. The most important ratio is between the crank and gen/alt pulleys for cooling, not the transaxle.
The Super Beetle’s had a higher ratio ring and pinion. That actually lowered the RPM’s in all gears when you ran the same MPH as the Standard Beetle with the lower ratio ring and pinion.
The two Freeway Flyers that I’ve had only lowered the RPM’s by about 350 RPM (ring & pinion and higher 4th gear) and 250 RPM (ring and pinion only) over a standard transaxle. That isn’t the drastic, 500-700 RPM drop like today’s Electronic Automatic OD with locking converters in our daily drivers.
VW designed the fan to turn a certain RPM at a certain ENGINE RPM, not MPH.
Note about VW cooling fans: Ever see one “explode”…it’s gnarly
. If you ever have your turbine fan out, check the hub area under the large nut for hairline cracks. Sometimes there won’t even be a warning vibration, a run up to higher RPM’s and WHA-BANG!!!Pink MG40767.4643402778
I stopped at my VW mechanic’s shop for his thoughts on this shifting question. He’s been working on Beetles and Porsches for nearly 40 years, and says that even here in Houston (where we’re heading into our 15th straight day of triple-digit highs) he’s never recommended keeping up the revs to cool the engine. Instead, he suggests adding an oil cooler, which mine had when I bought it. Running higher RPMs, he says, just increases your chances of experiencing one of those “gnarly” WHA-BANG! moments that Mark describes so eloquently.
1981 Lafer TI
1600 cc Type 1 engineI learn every day! Thanks guys!
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
For what it’s worth, I mostly run mine by the tachometer. I usually run it
between 2000 -4000 rpm. I am also going 60 mph in 4th at 3000 rpm.
An engine will generate more heat at a given RPM if you put a greater load on it. You get a greater load when you go faster, as with an overdrive transmission. That’s why there is a relationship between RPM and transaxle and cooling.
So while it’s true that the engine doesn’t know how fast it’s going, it’s not true that your potential speed is thereby limited only by your WHA-BANG redline.
Just sayin’.
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