After a run I always find an amount of dirt in my engine compartment. My compartment is not sealed, on each side at the back there are open areas, you can see the tail lights from within the engine compartment. Also there is a gap between the engine “surround” and the rear of the body below the rear lid latch. Should I seal theses areas? Would it improve cooling? It would keep dirt out of the engine area. Thank you.
Richard
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P.S. I believe VW and 356 engine areas are well sealed and aid in the engine cooling?
Yes. They are. Someone made templates for making the extra tin you need to bridge the gap between the VW tin and the Speedster bodywork.
I did a cursory search for it, but didn’t find it. Hopefully they’ll weigh in soon.
Cool, thank you.
Seeing the taillights isn't a problem. Seeing the ground is.
I originally had the same issue with my CMC - You could see a YUGE! gap at the rear of the engine compartment, so I got in there with a large sheet of brown Kraft paper and made a paper template custom fit to the openings I wanted to close. That included a "wing" at each end bent up at 90 to fully seal off that portion of the compartment.
Once the template was made and marked up for bumper mount bolts, tail lights and anything that I had to avoid, I transferred everything to a sheet of HVAC galvanized metal, then cut it out and bent the wings up and futzed with it til it fit perfectly.
Along the rear of the piece it is curved to fir the curve of the inside of the body and has a piece of door weatherstrip (Home Depot ) between it and the body to seal it up. The sheet sits on top of the rear body frame around the engine and is secured to that frame with a bunch of 10-32 screws.
Once installed, it completely seals that end of the compartment.
gn
I also made a template avoiding bolts etc. Took it to a sheet metal fabricator who cut it out of sheet aluminum that had a black finish. Approx $50 charge. Fit perfectly. I attached with several rivets tucked under the battery tray. Didn’t need many rivets as the aluminum was thick enough to provide good fit. It looks like it came from the factory.
CMC came with 4 (?) pieces of fiberglass - roughly cut to right shapes. One either side of where valve covers are and two in back above exhaust. The one above the lower one over the exhaust was to be fiber glassed in permanently but other were removeable so you could drop the engine. Add a bus H engine seal and you're good to go. The build manual calls for a rain shirt on either side of the flywheel toward front of car and the cutting of the 3/4 moon shaped fiberglass piece for fan cooling.
Thank you for all the replies. With a proplerly sealed engine would one still need an external oil cooler?
What size engine do you have?
Many owners with a properly sealed compartment use only the internal oil cooler.
Some report climbing temps during hot weather, while idling too long or during high engine load.
This can be related to engine size and how well the engine tins seal.
Many of us use both external and internal oil coolers, especially if they have larger displacement engines.
Some of us eliminate the internal cooler (block it off) to give better cooling airflow to the 3/4 cylinders and to move the heat to the wheel well where it is less likely to heat the engine.
I personally prefer the external only setup if you are seeing an overheating problem. Others should chip in with their preferences and experience.
@R Thorpe posted:Thank you for all the replies. With a proplerly sealed engine would one still need an external oil cooler?
There will be disagreement regarding this answer, but there shouldn't be.
The answer should be: "absolutely".
Some guy from the Yukon, running a 1500 cc single-port with 6.5:1 compression, who uses his car to putter around town between 8:00 and 10:00 AM, but only when the temperature is never above 60*, and never on the highway will likely pipe up and tell you he's been running without an external cooler for 45 years and never had an issue.
People who treat their cars like a car, rather than a curio piece need to be able to drive whenever they wish (or need) to. Most drag cars don't have any cooling system at all, but it's no more relevant to the discussion than the guy in the Yukon with his leaf-blower engine.
Can you guarantee you'll never, under any circumstances drive 85 mph on a highway in weather over 85 deg? No? Then add the cooler and all the attendant whatnot.
Michael,
Thanks for your reply, I have a 2332cc large engine with as far as I know the stock oil cooler. In addition I have a massive external cooler in the space between the engine compartment and the rear of the cockpit, with a fan.
That's a big one. Keep the external cooler.
If the external fan is working, you're probably ok on oil coolers. You might want to see if it has a thermostat to help it get up to temperature.
Are you seeing temperature problems? If so, sealing the perimeter and engine tin well is the next step.
Actually, the next step is to reach inside the fan and make sure it hasn't ingested a paper towel or two. Only an idiot would let that happen twice (he says to himself).
My previous Intermeccanica had a 2332 cc engine, with the oil cooler in the rear wheel well (fan attached), and all was fine.
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@R Thorpe posted:....I have a massive external cooler in the space between the engine compartment and the rear of the cockpit, with a fan.
Unfortunately, mounting the cooler there greatly reduces its effectiveness. At best, it doesn't cool much. At worst, it may actually become an oil heater.
Coolers are designed to be installed in a place that allows good flow of cool air in and good extraction of the hot air coming off the cooler.
When you box them up in a closed space, that space soon gets very hot, and all cooling stops.
So why did some replica builders put them there? Well, it's a very convenient place to mount something bulky like that, especially when the car is up on a lift and before the engine and transaxle are installed. Once the drive train is in, they're a nightmare to reach and work on, but - if you're the builder - that's not your problem any more, right?
Keep in mind that more respected builders didn't put them there.
My car was delivered new with a cooler in that space and it routinely overheated in warm weather. (In California, the term 'warm' is often a euphemism.) When we replaced the engine, we moved the cooler to the rear wheel well and there have been no oil temp problems since.
Mounting a cooler in the rear wheel well means fabricating a custom bracket that supports the cooler and also protects it from road debris. If you're trying to build a whole car in three weeks, it's one of the many little things you probably won't waste a few hours doing.
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I have to opposite problem because I live at elevation and in a cold climate. My engine will not get hot enough to produce interior heat below 38f. I have a 1915 with mild hot rod modifications. My external cooler is behind the firewall with a fan. I also installed a T Stat controlled valve that opens oil to the cooler at 90C. In the recent heat wave my oil cooler fan has come on a few times. Pulling Donner Summit in 102f at 75mph and nt gauge never reached the red zone. I have tested it and it is quite accurate for what it is.
Mitch,
So true, I’m thinking of running lines up front (not that far in this car) and putting a cooler up there.
@R Thorpe posted:Mitch,
So true, I’m thinking of running lines up front (not that far in this car) and putting a cooler up there.
If you put it up front, please at least get an Accusump.
And add a more powerful 30 mm oil pump!
.
Richard, most of these get mounted in the rear wheel well, for a few reasons.
First, there's obviously more plumbing when putting them up front, and I don't think there's any evidence that airflow and cooling are significantly better when the cooler is mounted up there.
But, long oil lines cause other complications. As @majorkahuna suggests, there's the problem of too much cooling in cold weather. You want the oil to get up to normal operating temperature as soon as possible and the long runs hamper that.
Even when mounted in the rear, most of these coolers are usually plumbed through a thermostatic bypass valve (the famous 'Mocal sandwich') that returns oil directly to the engine until it's hot enough to need cooling.
I think that's why Stan brings up the Accusump.
But, it could be he just likes saying 'Accusump'.
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I’m thinking of moving my oil cooler to a mount I will fab to an area in front of the front suspension at an angle to vertical. I will run lines on the drivers side to a thermostat switch where the cooler is now (between the engine compartment and the rear of the cockpit). Any comments? advice? Thanks.
Richard
Under the front bumper is where Porsche but the cooler as the 911’s engine grew in size. Not sure what was the first year but my last 911 an 83 Cab had it mounted forward.
The old turbo 911 had the oil cooler up front under the headlamp area. It had a thermostatic fan and a pebble screen. Make sure you get tire clearance during full turns and spring compression. The thermostat to speed up warmup was located next to the engine. There were no problems with the hose length or cooling.
Early 911’s had oil coolers in the passenger side front wheel well. 911T had a “trombone” type folded hard line. The 911S had familiar radiator type in the same place.911R’s had a cooler in the center of the front valence. None had electric fans an the thermostats set to 180 deg was at the engine on the passenger side.
The 911 also has a dry sump oil system and about 10 quarts of oil. That's a lot different than a T1 with like 2.5 quarts (ok maybe 4 with all the hose required).
@WOLFGANG posted:The 911 also has a dry sump oil system and about 10 quarts of oil. That's a lot different than aT1 with like 2.5 quarts (ok amy 4 with all the hose required).
Bingo.
How about just skipping the Speedster oil cooling quandary and just buy a 911 that already has it dialed in? 
I added an oil cooler with fan and temp switch in the passenger side rear wheel well. No need for long oil lines to the front. Works great. Temp gauge went from over 3/4 to hot to a steady 1/2. I am very pleased with the results.
My 77 911S takes 12 quarts on a change and the trombone cooler is in the right front wheel well. The run to the front of the car is done via brass oil lines as is the cooler which all aid in cooling.
All that brass exposed to the airflow helps in cooling.
There is absolutely no reason to run oil up to the front and back to cool oil in a Speedster. Over-complication for what benefit? Bragging rights?
I would not run oil lines up front unless I had a larger pump AND I used at least AN-10 lines there and back. All that length requires larger oil lines to reduce pressure loss. An old 911 uses oil lines of about 1", which is AN-16, and has a MUCH larger oil pump besides the dry sump tank and thermostat.
In a Speedster keep the lines as short as possible, but put the cooler in a spot with good airflow so it's effective(left wheel well). DO use an oil thermostat and a thermostat-controlled fan.
All these things are proven to work, and work well. There is no need to re-invent what works.
@MusbJim posted:How about just skipping the Speedster oil cooling quandary and just buy a 911 that already has it dialed in?
Or get Henry to build you one with a flat six. That will give you two oil coolers at the front, and all the piping you need.
IM-6 would be the and is the ultimate ACooled, and it has a dry sump system. I wonder how difficult it is to source out a 3.6 and a 915 tranny these days and what the cost would be for all the suspension components at this time of hyper inflation?
Is there a source/vendor for a bracket, etc. to do the left rear wheel well oil cooler mounting?
I built mine out off 1”x1/4” aluminum flat stock stainless nuts and bolts purchased at Home Depot . Less $25.00.
Hope this helps
@MusbJim wrote: "How about just skipping the Speedster oil cooling quandary and just buy a 911 that already has it dialed in?"
But then, maybe one wants the challenge of "Kit Car Building" but without the "kit".
OK, then....... I have just the thing, from our friend, Adam Wright at Unobtanium:
https://www.ebay.com/itm/284374048718
OK, so I admit that it might be a little drafty...... 
... at the risk of redundancy (OK, there's no risk. I've said all of this at least 10 times in the past)...
One of the weakest (scratch that. It's definitely the weakest, and by a wide margin) parts of the Type 1 is the archaic Rube Goldberg oiling system - in particular, the bypass pistons and the cooling system. The stock oil cooler bypass is a function of oil pressure, the assumption being that cold oil is going to be more viscous. This adds a whole 'nuther dimension to the car-guy's favorite hobby: the holy war regarding oil.
Oil cooling is even more of a problem in our plastic fantastics than in an old Beetle, because for whatever reason, the shape of the car doesn't do a good job of feeding cool air to the engine. We've talked that to death as well.
We talk of the Sainted German Engineers regarding may aspects of this little engine (air cooling system especially), but never with the oil system, because we all modify it whether we understand it or not. Everybody has an extended sump and a bigger oil pump. We run multi-viscosity modern oil. Everybody is afraid to modify the air-cooling system, but we all modify the oil system to one degree or another.
Regardless, a dry-sump (as used in a 911) is a fundamentally different way of handling oil than a wet-sump Type 1. In a dry-sump 911, the crankcase carries no oil other than that oil being pumped directly to the bearings. That oil, once it works through the bearings and drops out into what would have been the sump is swept up immediately with a scavenge pump. The scavenged oil moves through a cooler and filter, and then into a holding tank. A designer can pump that oil all over the car, because it doesn't need to be under any kind of meaningful pressure. Indeed, nobody knows what the oil pressure is in the scavenge oil side of a dry-sump system because nobody cares.
Once the filtered, cool oil makes its way back into the reservoir, the pressure pump sucks it out and pressurizes the oil in the bearings. The oil capacity of these systems is generally 2-3x as much as a conventional wet-sump system. The advantages are many - there isn't foamy oil flying all over the crankcase that the crankshaft is whipping through (windage). It's almost impossible to run out of oil, even if the car is cornering very, very aggressively. There's no extended sump at all, so the car can be lower to the ground without hitting anything (the sump is no longer the low point of the car, because there is no sump).
This is how 911s pump their oil up to the front of the car to be cooled, because the oil cooler in a 911 is in the scavenge side of the system.
A conventional Type 1 is a wet-sump system. The oil filter and cooler are in the pressure side, because there is only the pressure side. There are many considerations beyond pressure drop as well. What happens to the oil in the lines and cooler during the off-cycle? Does it drain back to the sump and overfill it? What happens on start-up? How long does it take to fill all those lines and that cooler, before the oil makes its way back to the bearings? A very good oil thermostat should theoretically close off oil migration when closed, and keep the cooler and lines full - but will it never leak by? At best, a system with a front mounted cooler would carry an oil level in the crankcase that varied wildly under different conditions. I can almost guarantee you'd run out of oil in various conditions... which is why I said that I hoped you'd at least run an Accusump (which is a completely different thing) if you did this.
In short, what a 911 does or doesn't do is irrelevant. A dry sump engine can pump oil anywhere you'd like, as long as it's on the scavenge side of the system. A wet-sump system needs a remote filter, short lines, a big cooler, a good bypass valve, a thermostatic fan switch, and an extended sump, none of which the Sainted German Engineers incorporated.
It's your car. Do what you want. There is more than one way to skin the proverbial cat, but as Danny alluded (and as I have belatedly discovered after years of incinerating money and time), one is not likely to have an "aha" moment that nobody has ever tried before. These engines have been around for 80 years. Stuff that works has stuck.
Great stuff, thanks to all.
I just checked on my 4-part article on mounting an oil cooler in the driver's rear wheel well and found that, thanks to our ex-friends at "Photobucket", none of the photos show up. 
Since it's a rainy day here in the soggy Northeast I'll take the time to rework the article series and re-attach the photos permanently to the posts for future reference. Should have done this a while ago, but it'll be done by this evening (I'm still futzing with seat belt mounts this morning). Stay tuned. I'll post when they're done.
gn
I'm about to install a 2276 that I built into an older Vintage Spyder. I'm using the CB dry sump pump. This has a 26mm scavenge pump and a 21mm pressure pump. A couple guys on shoptalk/thesamba have run these in races. As in track stuff and Baja S.C.O.RE. stuff and had good success. No oil pressure or starvation issues have been reported. IMHO, a constant availability to a 21mm pressure pump is better than sloshy, foamy input to a 26 or 30mm pump. Foam doesn't protect bearings, non-aerated oil does.
I've modified the pump(plugged), case(plugged), and a full-flow pump cover(machined to clear the pulley). It's not plug-and-play for sure.
The oil is scavenged from the stock engine case, then out through the scavenge pump. The oil is sucked out of the case to the thermostat, to and from a cooler, then to the top of the round tank(Round is important, oil swirling down in a circle de-aerates better). Feed is from the bottom of the tank to the pressure pump, to a Wix 1515 filter, then to the full-flow oil gallery lubing the engine.
There should be no oil drain-back-into-the-case problem in the Spyder. That is the advantage, as the bottom of the tank can be level with the oil pump and sump. I've been running mine this way for three years, and it works well. There is never anything on the stock dipstick even after sitting for weeks.
