Track Elan

[Doc Fizzix]

I have never had much confidence in torque readings obained with "extras" and they are difficult to work with but at least it would be uniform.

Yes, the crow's foot will change the reading a very small amount but as the amount of torque increases the change caused by the "extra" becomes almost none existent. Also, longer torque wrenches are even less effected by the crow's foot. I do belive the key as you stated it the uniform presser.

[Dave M]

As for checking that the surfaces are "true" I am talking about any time you are re-using a part. Yes I agree that a new turbo should be flat and true but it is always good to check and make sure. Nine out of ten times I am sure the surfaces will be true BUT if the surfaces are not true you will have problems down the road that is why it is good practice to check parts carefully durring assembly.

I had an Esprit-driving friend suggest taking a sharpening/polishing stone to the surfaces. He says he does this to all his turbo connections where proper gaskets aren't available and doesn't use gaskets and hasn't had problems. Sounds very anal and time-consuming...therefore perfect for my project!

FWIW, the SS gasket Russ mentioned above that comes for the T3 inlet worked just fine. I'll be getting another for that side of the adapter and see if I can't make another work between the adapter and the manifold. Then I'll take a stone to the downpipe inlet while I wait for the turbo to be fixed.

[Dave M]

Those new links are pretty! Just think of the weight all around that can be saved now that you have started down this road

Oh, yes...I've thought of all sorts of things to create out of aluminum or high density plastic (which this guy also works with). Though to do what I want I'd have as much money in my car as an Elise...and it'd still weigh more!

[Dave M]

I'll continue with most updates at this thread including the new turbo, but for now as I work on the brakes, I'll post at the following in case someone needs to look up adjustable proportioning valves at some point.

http://lotuselancentral.com/forum/viewt ... 4777#84777

[Dave M]

Well, back again after a summer of mostly non-Elan related things (travelling to see family, kayaking, motorcycling, etc.). After the spring fiasco with the turbo, gaskets, and brakes, I went into hold mode waiting for the turbo to come back and never really got the fire in me to work on the car much, even after the turbo came back. My new position at work has been taking up what little free time I used to have to surf the forum, so it was mostly free time at home to log on - which was nil. Now that the kids are back in school and they're back on a schedule of earlier bedtimes, I've got a little more time in the evenings. DSL and setting up a wireless router in the house helps, too! That way I'm not stuck in my office in the basement late at night logging on to dial-up.

Things have moved slowly on the car but at least have moved. I finished the braking system last night and so far, so good. No leaks, which I'm thrilled about considering the 20 new or reconnected brake line fittings I made as part of this! My timesink has been the exhaust manifold. When I took the turbo out after the exhaust leak, I should have sent it into Jet-Hot for recoating right away. The manifold was so nasty with exhaust (the car was still running rich when the gasket let go), it never came totally clean - just a dingy shade of grey. Long story short: Jet-Hot should have the part back to me in a week. Despite the coating not being easy to clean, kudos to the shop as they are recoating the piece free - I didn't even ask them to. Once that is back, I should be able to have everything installed quickly. The fire *is* in me to get the $#^%$ car on the road before it gets ugly around here when the snow flies.

The only other thing I'd like to do soon is have a new adjustable FPR installed so the car can be properly tuned. I've bought another spring for the external wastegate, so it should allow for 18-20 psi, instead of the 10 I had before. That way I'll be closer to the final product, at least as far as the engine is concerned!

[F1 LOTUS]

Good to hear you're able to get back to your project
On the subject of brakes, any more thoughts on the fade that you felt last time out? You're running 10 3/4" x 1 1/4" AP's aren't you?

[Ashaman]

The only other thing I'd like to do soon is have a new adjustable FPR installed so the car can be properly tuned

What are you going to do with that? Aren't you still running 550cc injectors & the S-AFC?

Do you think the new wastegate will lead to a quicker spoolup time?

[Dave M]

Hi guys. Yes, Brian - I am running the AP rotors you mention. My thought are the fronts are getting so much grip at a decreased level of pedal pressure, I'm never pushing the pedal hard enough for the back brakes to *really* work. Therefore I'm stopping only with the fronts. Hence the fade and the dive I get under braking.

Josh, I do have the 550cc RC injectors, but I'm no longer running the Apex'i unit. After the engine break-in and the first dyno, the engine guy thought all I would need would be either different injectors (which I had a hard time finding) or the adjustable FPR. Since we only dynoed at 10 psi, I thought I'd leave the 550s in and go the FPR route since the plan is for ~25 psi. I'll see what headroom I have at that level. As for the external gate, while I don't think it will make much of a difference from a spool-up perspective, it should control higher boost MUCH better than the stock flapper valve. The dyno at 10 psi showed it to be rock solid.

This weekend I modified the metal gasket I had for the turbo to also fit the other side of the manifold spacer/turbo adapter. The manifold is back from Jet-Hot (who recoated it at no charge - that was very nice and unexpected!) and I mounted the turbo this weekend. Blue Loc-tite on all Grade 8 bolts so I expect no leaks and a near permanent mount. Things will go back in this week along with a new transmission output shaft oil seal to hopefully cure my leak and I could drive by the weekend. No snow in the forecast this week at least!

[Dave M]

I've also updated things on the braking write-up. I posted some pics of the finished product with the adjustable proportioning valves.

http://lotuselancentral.com/forum/viewt ... 8&start=20

[Dave M]

Personally, I would say do not bother with copper gaskets for the turbo.

I did this and have had to replace them, they melted. My exhaust temps might be lower now than they were then, but I still don't think they are necessary.

Going back a little bit to this issue...I've worked on the turbo "out" and downpipe "in" surfaces for a bit now and may have a problem getting them perfectly flat short of having them remachined. The Jet-Hot coating is incredibly tough, and while the turbo side is relatively clean, the downpipe is still a bit coated. Even after multiple grit sandings, it still may be an issue. FWIW, I have done stainless gaskets for the turbo and manifold spacer connections, so no worries (hopefully) there.

Therefore I'm looking at making a copper gasket as suggested by my engine builder. I *am* concerned by your experience Josh with them melting. However copper's melting point is 1084 C / 1984 F, so I'm guessing your material was a mix, perhaps? I'll see what I can do about getting a thin, pure copper sheet to work with.

[Doug]

I'm no metallurgist, but pure copper is pretty soft! Just in case you hadn't been thinking about that . . .

[Dave M]

I'm no metallurgist, but pure copper is pretty soft! Just in case you hadn't been thinking about that . . .

Yup...that's probably why it makes a good gasket! In case you were looking for other gasket materials, here's an interesting chart:

http://en.wikipedia.org/wiki/List_of_el ... ting_point

Gold isn't too far away from copper, so the "blingmobile" could've gone that route if Gerome had kept it!

[Ashaman]

Man, I don't know then. I know the EGTs were way up there (I was getting some pretty bright orange from the snail) but there is no way it was THAT high.

Honestly, I thought the melting temp was lower than that; so I am not sure what was going on. I think when I got the car they looked like they were melted. They had like a .25"=.5" path gone from the inlet area out to the edge so the exhaust gasses leaked by.

So, thinking copper would be the way to go, I bought some copper sheets and made new gaskets. They failed in the same way a short time later. So I don't know what the reason was then - but it couldn't have been "melting" given the temps. Well, unless maybe they weren't pure copper like I thought they were.

Whatever they case then - I was suffering failures due to pieces of the gasket suddenly going missing. (That's my technical assessment of the situation). After using that super-gasket they stopped going missing; so I am happy with it

Those steel/fiber mesh type gaskets are supposed to be good for sealing mismatched mating surfaces; you could try one of those. Unfortunately, I didn't have much luck with those either!

[Costas]

Dave my custom made gusgets have outer layers of Copper. No problems so far after almost 2 years of using them even at 1.8bar (400+hp), but I do replace them just in case every 6 months or 20.000km. If my memory serves me correctly (in my case) its almost double the thickness of the stock one.

[Costas]

Those steel/fiber mesh type gaskets are supposed to be good for sealing mismatched mating surfaces; you could try one of those. Unfortunately, I didn't have much luck with those either!

They do Leak like hell after some hard driving, so NO GOOD for track use.

[Dave M]

Whatever they case then - I was suffering failures due to pieces of the gasket suddenly going missing. (That's my technical assessment of the situation). After using that super-gasket they stopped going missing; so I am happy with it

Thanks, Josh. I assume the gasket you mention is the one from slowboy racing? If so, then I am actually using the same gasket in between the manifold and the spacer/adapter, and another between the spacer/adapter and the turbo. I believe this is the SS gasket that Russ (houdini) also mentioned. The one from ATP has a raised lip to it that helps seal as it is compresed. Previously I had only used one of these, and it had no leaks whatsoever. So I adapted another one this time.

The copper gasket will go between the turbine out and the downpipe. Do you remember what thickness you used?

Costas, thanks for your info, too. I believe my head gasket is similar. I know we upgraded from the stock material. I hope to someday have the car tuned to 2.0 bar, so I'll see how it holds.

[Costas]

I hope to someday have the car tuned to 2.0 bar, so I'll see how it holds.

Cant wait! Ive never been over 1.8 so far and I doubt I ll ever try to...

[Dave M]

I hope to someday have the car tuned to 2.0 bar, so I'll see how it holds.

Cant wait! Ive never been over 1.8 so far and I doubt I ll ever try to...

Well, I'm one more step closer now. The copper sheeting came in, so tonight I make the gasket and test fit things. I'm unfortunately gone this weekend, otherwise I might have her on the road. With luck, it'll be end of next week. Then off to the tuning shop to install the new FPR and really make it fast.

[Dave M]

Here's the scratch template I made first to get the rough gasket, then I took my time lining up/drilling all the holes and got all the final adjustments with a Dremel sanding bit. No, I didn't cut the copper with those scissors! It's too thick (24 ga.) and required a cutting wheel.

[Monty]

Nice pipe work Dave