Frank818 -1993 VW VR6 Turbo donor- Build Thread

[choobs]

15-08-15

It does fit. I repeat: IT DOES FIT. Things are tight in some areas, but workable.

Nice! Congrats man, certainly is tight in a few spots but nothing that isn't workable. I'm surprised at how high the transmission appears to sit! I had initially thought that an Audi 01E would be a good fit but that trans sits pretty low. How much distance do you have between the transaxle and frame?

[mikeb75]

15-08-15
It does fit. I repeat: IT DOES FIT. Things are tight in some areas, but workable.

Congrats; you sound a little excited Very good news to see that all your prep & detail & sweating the details are going to pay off in the long run - and score you a crazy unique build in the 818 universe! Looking forward to first start & go-kart videos

[Hindsight]

Nice work! Doesn't look like it will be too much trouble to update the bracing. That thing is going to be a BEAST!

[Frank818]

Tnx all for the nice comments, I take them all like a big shake of protein in order to pursue the build with the 1000s more details to design and fab.


Choobs, which part of the frame/trans you want the measurement for?
Thing is, no matter the trans you use, that VR6 only has one place to fit in the engine bay. Higher and you are in the red for the body panels. Lower and the pan will be lower than the frame. Luckily, the INA longitudinal VR6 pan is 0.5" higher than OEM pan. I have not fitted it yet, but we agree that 0.5" is almost nothing, you have nothing to play with in terms of height. Unless you don't mind medium to important body work on the deck lids.

My original plan for this build was to accept minimal frame mods and very minimal body mods. It seems I got lucky and my guesstimated measurements where within thresholds.

[choobs]

Choobs, which part of the frame/trans you want the measurement for?

Lets try this: distance from the bottom of the oil pan to the lowest point on the transmission. And also from the lowest point on the transmission to the highest part of the frame just below it. If that makes sense...

Also, i'd be doing this swap into an 818c which looks to have a bunch more room to move the engine up if needed since there are no panels covering the engine as part of the aesthetic. I can pretty much make what ever I want to cover the engine. When you had your CVs made, did they only grind the shafts and you are using your own inner/outer joints or did they make the whole assembly for you ready to bolt in the car?

[Speedy G]

Choobs, remember the most important measurement is the front of the engine to the axle centers. The G50 tranny barely makes it possible and it pushes the VR6 a little forwards from where the engine would sit with the subie tranny. However, since the 01E is a FWD tranny, it'll most probably give you more room than the G50 and similar to the subie tranny. My guess it you'll have plenty of room and have the axle centers where they're supposed to be. One thing you should verify is the height of the VR6 with the O1E installed. It looks like the axles sit lower than on the subie tranny, which would mean the VR6 would need to sit higher, which would mean bad news. Btw, remember that the G50 is upside down, that's why it looks like it sits so high. Check out a pic of the 01E:



Speedy G

[Canadian818]

Congrats Frank, HUGE milestone. I remember you talking about maybe using your VW's engine way back, (years?), and I was thinking there's no way. But once you set your mind to it there was no stopping ya, you've been determined. One more confirmed fitment! You'll always be the first.

[choobs]

Choobs, remember the most important measurement is the front of the engine to the axle centers. The G50 tranny barely makes it possible and it pushes the VR6 a little forwards from where the engine would sit with the subie tranny. However, since the 01E is a FWD tranny, it'll most probably give you more room than the G50 and similar to the subie tranny. My guess it you'll have plenty of room and have the axle centers where they're supposed to be. One thing you should verify is the height of the VR6 with the O1E installed. It looks like the axles sit lower than on the subie tranny, which would mean the VR6 would need to sit higher, which would mean bad news. Btw, remember that the G50 is upside down, that's why it looks like it sits so high. Check out a pic of the 01E:



Speedy G

Thanks for the info Speedy. I thought I had read that the G50 was flipped over but that was many a beers ago I am trying to confirm with F5 what the situation is with the 818c and any type of engine covers. If there is no engine cover panels like 818s has then height of the engine shouldn't be a problem and allow me to stick with an OEM oil pan/oil pump. Would also cut down the need for an SRI over the stock intake as well. CV axles are another story but I'm looking into options.

[Frank818]

Lets try this: distance from the bottom of the oil pan to the lowest point on the transmission.

The engine is out now, I'll see if I can find something on my pix, that would be close to 4".

And also from the lowest point on the transmission to the highest part of the frame just below it.

Nil. But we will raise it a little by 1/8" to clear the frame and/or grind flat the round edge of the adapter. It's the bell housing to engine adapter causing this, so close to the frame.

When you had your CVs made, did they only grind the shafts and you are using your own inner/outer joints or did they make the whole assembly for you ready to bolt in the car?

They have not built them yet. They will be custom chromoly shafts with G50 inners and upgraded Subaru outers (more solid with bigger splines). The assembly will be complete for bolt-on.


As for Speedy's comments, yes the G50 is upside down, unlike on the 01E picture. Using a tranny like the 01E will raise the engine too much (for me). Besides, the 01E had many other drawbacks I could not live with.
If you want to fit the 3.6 with a tranny not upside down, having the bell housing higher than the axle centers, it will raise the engine, maybe just a few inches though.

Congrats Frank, HUGE milestone. I remember you talking about maybe using your VW's engine way back, (years?), and I was thinking there's no way. But once you set your mind to it there was no stopping ya, you've been determined. One more confirmed fitment! You'll always be the first.

Tnx a lot Mr Rotary, same to you actually!

[choobs]

As for Speedy's comments, yes the G50 is upside down, unlike on the 01E picture. Using a tranny like the 01E will raise the engine too much (for me). Besides, the 01E had many other drawbacks I could not live with.
If you want to fit the 3.6 with a tranny not upside down, having the bell housing higher than the axle centers, it will raise the engine, maybe just a few inches though.

Probably the best method would just be to have everything sitting in front of me and make some measurements. Thanks for the help Frank!

[choobs]

Frank - the 3.6VR block has the same dimensions as the 2.8 and even the same mounting bosses. Intake and exhaust manifolds can swap over too. Biggest difference is the 3.6 is fsi so it needs its fuel controller and specific fuel pump but the bottom line is, if the 2.8 fits...so should the 3.6!

[Frank818]

Same dimensions? How the hell did VW make that happen? I mean the 3.6 has 89mm bore and 96.4 stroke. I know a 95.6 stroke fits on the 2.8/2.9 (stock is 90.3), making it top 3.1L using 83mm bore, but on the bore anything over 84 is really on the edge, maybe 85mm but don't force air into the 84+ bore, the walls are getting very thin. How could they manage to fit 89 in there if the block has the same dimensions? On top of that, the angle has gone from 15-deg down to 10.6, which makes either the pistons closer or the block longer and possibly the engine higher since the long crank is more vertical. Those VW engineers will always be full of surprises.

But if you are sure the dimensions are the same, especially the length, then yeah, if the 2.8 fit, the 3.6 will.
How are you getting hands on that rare engine? Are you from Europe?

300/260, that's about what Metalmaker has with his WRX engine and his car is a blast (lighter than with the 3.6 though but still).

[choobs]

But if you are sure the dimensions are the same, especially the length, then yeah, if the 2.8 fit, the 3.6 will.
How are you getting hands on that rare engine? Are you from Europe?

I find it a little hard to believe too but the offset angle from the pistons relative to the crank is 12mm in the 2.8 and 22mm in the 3.6 which should also help keep the package smaller. I have the believe it is a little longer due to the piston bore but if people are swapping them into other VW chassis' using stock transmissions and CV shafts then it seems to reason the blocks are very close to similar dimensions.

I'm in the USA, these engines are used in several VW products from B6 & B7 Passats, CC, Audi Q7,etc. I believe there was a smaller 3.2 developed but that was a euro only fsi motor.

[Frank818]

Yeah the market is better in USA for these cars, although the Q7 is more common around.

There is a 3.2 since the R32 of course. Not sure the recent ones (2008+) are FSI, but it's still far from 300hp stock. As long as you get a longitudinal 3.6 it will save you the hassle of a new oil pan and oil pump.

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For some reason I couldn't get a nice focus.

The turbo oil return line will be where the white rag is. That reminds me I forgot to take measurements for the length of the line so that I could order it today. Damn it! I'll try to remember on Saturday when I go back.

[Frank818]

A lot of clearance issues occured, as expected.

- We had to offset to the left the entire drivetrain by about 2-3", otherwise the Porsche racing starter (Chad certainly knows these) was hitting on the lateral link bracket. You cannot fit the standard Porsche starter, it's WAY too big, would require major frame/suspension modifications. Luckily my mech took off his new racing starter from his racing Porsche and it fits. I admit it looks awesome with the gold too. That starter however sits 1/2" lower than the tranny support bars, which means I will have to space down the rear diffuser in order to fit it, or cut a hole in the diffuser, which I don't want to do at all. And, that's not all, the washer on the starter is about 1mm from the tube. My mech thinks it won't touch cuz the engine will not move, but I don't trust that, so he will grind off one side of the washer to clear more.

- Then, by offsetting the engine, my cooler doesn't fit anymore. I have to completely redo the bracket and positioning. That really sucks. Might also screw up the corner balance! I don't think I'll be able to have something perfect.

- On the back of the tranny, where there is the plate with 2 big holes on the frame, one place rubs on the bottom protrusion of the tranny. That is easy, I will cut a line in the plate and that's it. No picture of that clearance issue.

- The axles are about 4.5" rear of the CV centers. A lot, but not too much. I will have 2 different length axles, by about 2" apart.

- The engine will not sit too high, 2" up front and 2.5" on the oil cap. I will try to sit the hump panel at 3" to give me enough clearance for overkill heat shielding. My turbo sits high compared to yours!

- The engine mounts are on a plate. The plate is not reinforced with diagonal flats, I do not fully trust the way it is now. I will weld diagonal flats each sides of the plates later, that can be done when the engine is in anyway. The tubes and plates used for my engine mounts are 3/16 thick, which is almost twice as thick as FFR's tubes (0.100"). Of course, you guessed, that will add even more weight to the car! I damn hope I can make it under 1000kg but I'm not sure. That sucks too. Not the fact I'm not sure, but the fact I may bust 1000kg.

- One good news though, my intake to turbo inlet (including the filter) seems to be 90% bolt-on!!!! When I test fitted it, I was so damn astonished I just couldn't believe it! Something fits bolt-on on this crazy project? Impossible. The 10% not bolt-on is that on the clamp between the rubber and pipe the angle is not perfect so it twists a little the rubber, opening up a little hole. Clamping on that would put twist on the clamp most probably. The fix is to cut the pipe further down and clock it until I get the right angle inside the rubber and for the filter, or maybe cut it at an angle where it goes inside the rubber. Should be easy. For those still reading this lolll, do you think the filter is in the right place wrt the side scoop??

I think the setup looks pretty slick. The details are killing though, everything from a bolt, a nut, a pipe, a component, a wire, a bracket, everything needs adjustment or re-design.

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[Frank818]

Some more pictures.


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[Frank818]

And again more.


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[Frank818]

The final ones.


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[Frank818]

Yeah well, our 818s can't be beat them all in terms of G-forces...

GT3RS.jpg

[Hindsight]

Looks great! Were you able to position things so that the driveshafts will be parallel to the lateral links? It bothers me that the standard 818 has them pitched forward.

Those upper support braces you had to remove..... hard to tell exactly from the pics but it looks like you could add them back in, but instead of having them connect near the middle, you could have them connect a little further out toward the outsides. Obviously wouldn't provide as much strength as the original design but would still provide some good triangulation.

[Pearldrummer7]

Wow. This looks awesome. You've done some really cool work here. Looks awesome as always, Frank!

[Frank818]

Tnx Frank.

Hindsight, the driveshafts parallel back and forth with lateral links or up and down? They are neither. So many compromises, I take what I can get as long as it runs fine and we think there should be no problems the way things are right now, but the shafts are not parallel with anything. The wheel hubs are fwd from the axle centers on the tranny though, which is the way it should be. Not by 4.5" like now, but at least it's in the right direction.

That was my plan on the upper support braces, but I'm not sure how important they are on a street car. The upper round tubes connected to the rollbar already give good strength, not all in the right place but still. Then with the tower brace, it will give side-side strength too. But yes I will weld them back as close to the center as possible in a way that I can get the engine out without cutting them again, of course!


I did not mention, but we see it on the pix, we had to cut one portion of the X bars under the tranny and move slightly that small portion. The frame looks screwed up with all these little mods here and there, but it's either that or I fit a different engine and I will do anything to fit the VR6. If it doesn't handle well cuz of all these mods, well I'm screwed! lolll
If it was a race car, not sure I'd have done it with the VR.

[Hindsight]

I was thinking back and forth. Not sure how up and down is on the WRX-powered 818 but as others have noticed before, the driveshafts are offset with the wheels being more forward than the transmission output shafts. I'm sure it's probably not going to cause any issues so long as no binding occurs, but it's not very ideal when doing hard launches on a high horsepower build. I wonder why FFR set it up that way? Seems like it would have been easy to have it lined up. It would result in the wheelbase being slightly longer. Maybe they had reasons I'm not aware of, and I'm not an automotive engineer.

[Frank818]

It's supposed to be that way. Check out the new NSX (naked):

NSX drive shafts angle.jpg

Normally the wheels are less than 1" in front of the inner CVs. The reason I've been told is that on a launch the gearbox pushes fwd due to the rotation of the inner CVs while the wheels want to stay there, cuz the innver CVs are smaller than the wheels so they want to rotate faster. I'm trying to find an every day example but I can't.

I can't tell how true that is, but the above pic is from the NSX, which is a real car so I believe there must be some truth in there.

[choobs]

Looking good Frank! I think if you box in those motor mounts they should be plenty strong. Any reason you chose to add in square bar under the mounts this way instead of gussets out to an already existing piece of frame?

Also with regard to the valve cover near the firewall - I believe that is PVC mounting location correct? If you look at some of the 3.2l VR covers out there, this PVC mount point is moved to the other side of the engine near the oil fill cap. This might help you to install the frame rails back to their normal location (if that is something you are looking to do.)

[Hindsight]

It's supposed to be that way.

That's really good to know! I have seen others comment about it in the past and it didn't look right to me but.... shows you what I know!

[Frank818]

Choobs, I don't know the exact reason my mech decided to use the square bars (certainly not for weight saving!). Probably cuz it was simpler to build. And at this point I tell ya I want things as simple as possible so it can go as quick as possible. The locations where the VW mounts are are not ideal to use existing pieces of frame, definitely was easier to use the square bars, from a working design point of view.

PVC... that rings a bell, can't remember what it is? Oil evap? That engine has been stripped down a lot through the years and it only has oil evap left (no EGR and other stuff).
Near the FW on the valve cover I only got the oil evap hose to connect (below the top of the cover), which will direct to the intake piping inlet to the turbo about 2 feet away. I don't except any issues there. Nothing connects close to the oil fill cap. The R32 has hoses that go over the top of the cover, which isn't my case. My top top top part is the oil fill cap. I don't think I can buy a low profile aftermarket one.

As for fuel rail, nothing will route between the cover and FW, the fuel hose will come from the left side of the car and connect close to the intake manifold and into the rail, which is from the opposite side of an OEM VR6. At least I saved myself from some little issues here and there.

[Frank818]

Other milestone, the baby's back home!!

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I already have some impressions. Now I start to understand people when they get excited/crazy on their first start/drive. I had the chance to "flinstone drive" it when my friends where pushing the car into the towing. I mean not "into" the towing but on the platform.

Steering is heavy on very heavy parking manoeuvres. But not that much, enough so that I can't do it one hand, it doesn't bother me. But who gives an F about parking these cars? We don't buy them for that. Buy yourself a Yaris, damn it! lolll Besides, steering has really good feeling and no play.

The brakes. Wow, it really doesn't have the same feeling as boosted brakes. And they seem to stop the car so well with so little pressure, I can't imagine how overkill they are on the road. Overkill or not, as long as they work well and feel well, that's all I need.

The suspension. That was one of my concern. I thought it would be too stiff for roads here, even on their softest setting. I had the chance to go over bumps at low speed and I was impressed. Yet stiff, but far from harsh and far from shaking the entire car. It felt sporty, like a Porsche, well absorbed and still comfy. The front seemed a little stiffer, but I still need to add at least 80lbs, excluding the body for which I assume the weight is pretty much dispersed front-rear. It felt well balanced. I can't wait to try that suspension on the road for real!


Some more pix:

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That's the clutch slave of a Carrera 4, as the one from a C2 wasn't fitting in there.

Other things worth mentioning: the starter works and apparently its sound is interesting.
The damn clutch master was leaking so bad from the bottom I need to buy another one. So clutch is not bled.
The LCAs will never be levelled to the ground. The car sits currently at 4.25" and it's the lowest I can get (no body). I have to aim for 4.75-5 which will bring the LCAs even more less levelled.
The rear blue lateral links will never be levelled as well. They are levelled right now but like I said I need to raise the car, so...
Is it "that" important to get LCAs and links levelled? Not sure. Anyway they won't for me, so I gotta move on. lolll

[apexanimal]

if your wheel centers are 4.5" forward of the transmission axle centers, how far forward are the standard 818's (how much farther rearward are your transmission axle centers from the norm)?

[Frank818]

if your wheel centers are 4.5" forward of the transmission axle centers, how far forward are the standard 818's (how much farther rearward are your transmission axle centers from the norm)?

I don't know, I think it's 0.5", maybe 1" for Subaru drivetrain.
I believe my trans axles are quite over 3" rearward than Subaru's, maybe 4. But I have not seen that precise measurement (I don't see why Subaru drivetrain guys would need that measurement as it fits super easily no matter what) and I have not asked for it either. I wasn't concerned about distance between engine block and axle centers, I measured all that differently as my engine block probably don't sit where Subaru's does, so that distance was too risky for me to use when I "paper mocked-up" the VR6 fitment.

[apexanimal]

no worries - thanks for the info...

i'm thinking about a different kind of swap and was researching max safe inner cv joint angles and wanted to see the difference - thanks!

[C.Plavan]

Your transmission is run upside down. On the Porsches, the starter is on the upper left (in mid engine config). Looks good.

[Frank818]

no worries - thanks for the info...

i'm thinking about a different kind of swap and was researching max safe inner cv joint angles and wanted to see the difference - thanks!

Hard to tell. One thing for sure, I will let everyone know if 4.5" hold up. lolll

Your transmission is run upside down. On the Porsches, the starter is on the upper left (in mid engine config). Looks good.

On a Porsche, yes, on a GTM and 818, no. Porsche in a mid-engine using a G50? Which one?
Porsches have their engine in the back of the trans, as you know very well. I have the engine in front. Since I can't afford having 5 reverse speeds and 1 forward, I have to the flip the trans upside down in order to fool the trans with the configuration and make "her" think it's still on a Porsche. That trick is well known for people using this trans on a mid-engine setup and it works flawlessly if you know exactly the right amount of oil to fill in.

If I had to keep the OEM setup of that trans, it would never work on the 818 cuz it would bring the engine too high. Well for me it would be a no-go and I'd be using a 100% different drivetrain then.

[Frank818]

This build is a PITA. Everything, I mean every f** thing gets in the way of everything else.


2015-09-10 17.20.44.jpg

Now trying to design my intake piping and I have a lot of problem with the piping going from the cooler to the t-body. There is so little space I have yet to find a solution after about 3-4h of work. I need to fit a temp sensor and my BOV after the cooler and before the t-body. I need a 3" tube to attach to the t-body, a 180-deg tube needs to be very very tight, I have 8" of play between the t-body (far right) and frame tubing. Considering the in and out are 3" each, that means I need a 180-deg bend within 2". I couldn't find one.

You might think "yeah well just take it from under the t-body." Sure. But my shafts will be in the way. Until I actually have the shafts and test fit a 180-deg that way, I can't be sure it will fit or not.

There is no other location for the cooler. Unless I place it way far back of the wheel between the trans and wheel. Doing so will increase piping length to fill up and will increase lag. I don't want that. It will also put more weight back of the rear wheels. I don't want that either. I thought of buying a different cooler, but they are all slightly bigger (to accommodate 500+hp) and don't really give me better options, so for the price and not being sure until I test fit it, it's not worth changing. The fact my mech needed to offset the engine to the left to fit the damn starter has caused a cascading effects on the intake piping and I'm stuck with it.

Maybe I'll have to live with a cooler way far backwards.

I am not talking about design issues for the coolant and exhaust, there are a lot as well.

Again, this build is a real design nightmare.

[C.Plavan]

I was talking about the mid engine 901, 911, 915 transmissions (with ring flip kit from Kennedy). G50 has to be flipped, no mid engined g50's. Some old 935 race cars used the the 930 transmission with a flipped R&P. No such luck with a G50. I personally would of sold the g50, and recovered some cash while using a different transmission.
But then again, I would not have been doing what you are.

[Frank818]

Those might be different setups, I don't know. All I know is if you take a G50 from a 1988 911 rear engine, you gotta flip it on a mid engine. There may be other solutions with R&P or something else, but I have not explored those as I need the engine to sit low anyway (it is the lowest it can now and even that the damn starter goes 1/2" under the frame).

I did not find any other trans that was good enough (some yes, at 10k+). Gear ratios, cost to change ratios, ratio choices, engine height, trans length, strength, etc., all that was a problem on all the other ones I checked. Recovering cash by selling the G50 would be spent to fix other issues the other trans wouldn't handle. The G50 has no issues, a little high priced but I get a lot for what I pay for. Besides, the trans is not causing me important problems right now. It's the engine that is.

No, you wouldn't do what I am doing now. Stay with your oil temp issues (which you'll fix soon enough), it's much better and easier than a build like mine! I actually envy your oil issues.

[choobs]

This build is a PITA. Everything, I mean every f** thing gets in the way of everything else.
Again, this build is a real design nightmare.

If it was easy, it wouldn't be any fun! Minus the turbo kit this build would be easy peasy.

[Hindsight]

What cooler are you using and where are you locating it?

[Frank818]

It's not fun if it's too easy, yeah, but there's a limit. Taking too much time on one single simple thing is not that fun. Taking time to optimize something, that's fun. And optimizing is usually not easy.

I am using the cooler Schimmel Performance (spturbo.com) sold me 10 years ago (not on the website anymore). It's about the same size as type 10 and 16 at frozenboost, but a little smaller (0.25 to 0.5").
I don't know where I'm locating it, that's the whole debate taking me hours to figure out. I have to close this this w-e.
I guess I'll try again over or on the side of the trans, just rearwards of the shafts. Probably 1 foot longer piping there, but maybe not! I have to check. I'll sacrifice on lag 0.1-0.2sec in order to simplify the installation of that damn piping, cuz I'm almost fed up, I mean I'm not yet at the point I check on the piping, I'm still checking where to fit that cooler in the first place! And I have to check for my muffler too, I don't want the muffler or exhaust to get in the way of the intake piping I'd design. Plus I have to make sure the tower brace will fit, which is not now cuz I need to cut and flip the bars and weld, so I don't know where it'll sit. I have to guess all that at the same time, otherwise one of these things will not work and I'll have to start all over again. That's why I say it's not funny. I can't think of one thing at a time, I have to picture everything in place at the same time, but each thing impacts the others, I move one thing a little bit, it screws up the entire design of 10 parts. That's the thing.

An OEM VR6 would be a FREAKING JOKE TO FIT! Turbo is different and I don't think a SCed VR6 would fit, cuz the SC uses space on the pulley side and there is no space there in the 818.

[Hindsight]

I can't think of one thing at a time, I have to picture everything in place at the same time, but each thing impacts the others, I move one thing a little bit, it screws up the entire design of 10 parts. That's the thing.

If it makes you feel any better, it's the same for me. That's part of why my build has progressed so slowly. But I'm happy with the outcome and the (so far) lack of re-work. It's a puzzle and all the pieces have to fit together.