I'm curious about the reasoning behind this exhaust setup.
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Yeah, there are some interesting choices there. I've never seen a chain used to hold the clamshell open.
I can assure you that wasn't built by the boys in Indiana.
Dry sumped! That's good!
But also: 
And the fuel line runs all the way to the back of the car then does a 180 to go 2-3 feet forward to the carbs. Lots of lines and hoses and wires routed a lot of ways.
Aluminum underpan in the back! Very cool, original type touch! That's good.
But...it's under the exhaust. Keeping the heat in! That's bad.
Needed 200 more studio shot photos.
@edsnova posted:Dry sumped! That's good!
But also:
And the fuel line runs all the way to the back of the car then does a 180 to go 2-3 feet forward to the carbs. Lots of lines and hoses and wires routed a lot of ways.
Obviously a “belt and suspenders” kind of guy. That engine compartment is pretty busy.
A couple of years ago a guy approached me at a show and told me he was working on one. It had an exhaust somewhat like that. Same headers, but it dumped into a big tin box, then had a single exit pipe. I was curious as to what it sounded like and damn if it didn’t sound almost like a Subie with a fart can.
The story they told was the owner used to club race it and they were modifying it to get it ready to license for the street. I drove mine out to their shop and let them take some pictures of how some of the things on mine were done.
ps: surprised the BaT ad doesn’t mention the DTM shroud. DMR @ $32K.
@edsnova posted:
… and I thought I made things overly complex.
Are those fins on the dry sump tank?
The BaT car has an exhaust that looks a lot like the Formula V exhausts in Danny's pictures. I believe the car in Rick's pictures has a T4.
@Stan Galat posted:The BaT car has an exhaust that looks a lot like the Formula V exhausts in Danny's pictures. I believe the car in Rick's pictures has a T4.
It is Stan, good eye!
Based on what I’ve heard about heat-related starter issues, I’m not too sure that exhaust is such a good idea. Not to mention, between that and the oil tank, one of the best features of a Spyder is negated: the accessibility of the engine.
It's indicative of the whole build. Lots of work, pretty well done, to make it worse, for...some reason?
In the auction he talks about the throttle linkage, how he was tired of dealing with the "heavy crossbar system." Look at it.
It’s a crazy amount of reinventing the wheel, when a Vintage Speed throttle would have been 2X as elegant.
I wonder if the builder's parents are both German, because this engine bay is REALLY complicated. And for no particular reason.
The DTM shroud with the type4 cooler is very efficient, making an external cooler superfluous.
The dry sump tank is huge and square, but it goes there because there isn't room at the firewall(Beck, torsion tube).
I didn't know that my hexbar linkage was "heavy". More likely he couldn't get it to work. Simple geometry fixes that.
That engine bay reminds me of Thomas Dolby's "She Blinded Me With Science":
"all those tubes and wires, careful notes, and antiquated notions"
I almost always agree with Danny.
However - I have a DTM with a T4 cooler on the stand, and it doesn't make a remote cooler superflourious. A remote oil cooler is still a good idea, and needed on most days when the O/A temp is above 80 deg.
The fact that this guy went to the trouble to dry-sump and then didn't employ any remote oil cooler is mystifying. With a 2-stage pump, he could pipe oil to the front of the car and cool it with air pulled in through the nose grille and never lose pressure in his bearings at all. It's ideal for any kind of truly remote oil cooler he wanted to use.
The car is a mess.
Well, I was told that, but didn't have my own experience there. Sorry.
You are absolutely correct that an aux cooler could easily be installed in the suction/evacuation side of the system. That's how I ran mine.
On the pressure side, I have about a foot from the tank to the pump, then direct to a filter(with overpressure bypass to tank) then right to the main gallery.
That car IS a mess.
@Stan Galat posted:However - I have a DTM with a T4 cooler on the stand, and it doesn't make a remote cooler superflourious. A remote oil cooler is still a good idea, and needed on most days when the O/A temp is above 80 deg.
Taking this point one more step, I'd ask why one would ever want an oil cooler mounted in the stock position on the engine. It seems to me that moving as much of the oil heat outside the engine compartment possible is a good rule of thumb. Only cooling the oil with a remote cooler should lead to cooler compartment temperatures and by extension, cooler intake air temperatures and more HP. Does this sound reasonable?
@Michael Pickett posted:Taking this point one more step, I'd ask why one would ever want an oil cooler mounted in the stock position on the engine. It seems to me that moving as much of the oil heat outside the engine compartment possible is a good rule of thumb. Only cooling the oil with a remote cooler should lead to cooler compartment temperatures and by extension, cooler intake air temperatures and more HP. Does this sound reasonable?
It does, and I concur.
The stock oil cooler is why the dual relief oiling system is a mess. Eliminate the cooler in the stand, and eliminate an entire bypass setup. Install a JayCee bypass oil filter mount and eliminate the other.
Yup to both Michael and Stan. My setup has eliminated the factory cooler using a block-off. I have the 911 fan shroud which has no cooler under it. I have a 96 plate Mesa cooler, oil thermostat, and thermostatic fan.
Honestly, it overcools when ambient temp is below 60. Above that, I have oil temps in the 180-190 range.
Well. Yes, and...
The DTM "factory" oil cooler is the main improvement over VW's version. The oil cooler is larger than a stock Type 1 and its housing gets its own air from that funky tube curling around the hole. That should give nominally better oil cooling than a VW stock doghouse. Right?
But what most guys—especially Spyder guys—overlook is the exhaust port from that oil cooler doghouse. It's low, but not low enough to direct the heated air under the car and away from the engine bay. That is why I
As it turned out, even with that air shunt, my car's oil temps were borderline high (~215F) on warm summer days when driven at medium speeds, so I added an auxiliary cooler, fan and thermostats. Now the oil temp seldom exceeds 180F.
Honestly, I wouldn't consider 215-220F borderline today. I'd say 220 is the upper limit, 230 cause for concern, and 240 is downright scary.
But today's oil at 215F is just fine. And you change it often, yes? I wouldn't have gone to the complexity of the aux cooler, especially with a 1915cc. The cooler won't hurt you, so you're good, Ed.
*** You really want the oil to be at least 180, more like 190-200. That is a great running temperature. Minimum 160 or you're not getting rid of the condensation in the engine case. (That right there is the entire WHY of the start it, idle it for twenty minutes, then put it away in winter months is BAD for your engine.)