As i need more posts, here is my N/A build !
11-19-2008, 08:48 AM
#27
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it is basically a trackday car, for road racing circuits of course as there is not really that much drag and autocross stuff here in Europe.
It just has to keep the "gentleman driver" spirit, which means it has to go to the track and come back from it on the road, and not using a trailer, so has to keep this at least a bit streetable
It just has to keep the "gentleman driver" spirit, which means it has to go to the track and come back from it on the road, and not using a trailer, so has to keep this at least a bit streetable
11-19-2008, 08:55 AM
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it is basically a trackday car, for road racing circuits of course as there is not really that much drag and autocross stuff here in Europe.
It just has to keep the "gentleman driver" spirit, which means it has to go to the track and come back from it on the road, and not using a trailer, so has to keep this at least a bit streetable
It just has to keep the "gentleman driver" spirit, which means it has to go to the track and come back from it on the road, and not using a trailer, so has to keep this at least a bit streetable
11-19-2008, 12:20 PM
#30
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What is not pictured :
The head is skimmed 1.4 mm, the Sivalves add 0.25 CR by side (so 0.5 int + exh) due to them being less dished than OE items.
We are using a Cometic LSJ .027" head gasket too, so depending of the 'yet not 100% certain' stock head gasket thickness, we are something in between 12 and 12.4:1 CR.
The head is skimmed 1.4 mm, the Sivalves add 0.25 CR by side (so 0.5 int + exh) due to them being less dished than OE items.
We are using a Cometic LSJ .027" head gasket too, so depending of the 'yet not 100% certain' stock head gasket thickness, we are something in between 12 and 12.4:1 CR.
btw stock headgasket thickness I believe is .040" for the L61
awesome build btw
11-19-2008, 12:43 PM
#31
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The 10:1 were an easy solution as it normally is just a first development engine (but built to be reliable).
Reaching a high CR with a skimmed head is not optimal... in terms of reliability of course as it weakens a bit the head, but with flat pistons too : the swirl of the air/fuel mixture may be worse than with real high CR domed pistons with valve dishes.
Will normally be sorted for the second engine, but that's a story for another day
Reaching a high CR with a skimmed head is not optimal... in terms of reliability of course as it weakens a bit the head, but with flat pistons too : the swirl of the air/fuel mixture may be worse than with real high CR domed pistons with valve dishes.
Will normally be sorted for the second engine, but that's a story for another day
11-20-2008, 08:01 AM
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I am very impressed. Awesome car to build off of. And as for it being a track car then drive it home is also awesome.
I will be watching for more videos and numbers.
I will be watching for more videos and numbers.
11-25-2008, 03:55 PM
#36
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Warning big pic
http://farm4.static.flickr.com/3178/...34655b03_o.jpg
So this is the source cause of my external oil cooler failure
All these few particles blocked the pump valve reflief piston which led to a much too high oil pressure for the oil/water exchanger
Everyone that have a high rev limit should be warned, just as the build book try to say
http://farm4.static.flickr.com/3178/...34655b03_o.jpg
So this is the source cause of my external oil cooler failure
All these few particles blocked the pump valve reflief piston which led to a much too high oil pressure for the oil/water exchanger
Everyone that have a high rev limit should be warned, just as the build book try to say
11-25-2008, 04:08 PM
#37
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Warning big pic
http://farm4.static.flickr.com/3178/...34655b03_o.jpg
So this is the source cause of my external oil cooler failure
All these few particles blocked the pump valve reflief piston which led to a much too high oil pressure for the oil/water exchanger
Everyone that have a high rev limit should be warned, just as the build book try to say
http://farm4.static.flickr.com/3178/...34655b03_o.jpg
So this is the source cause of my external oil cooler failure
All these few particles blocked the pump valve reflief piston which led to a much too high oil pressure for the oil/water exchanger
Everyone that have a high rev limit should be warned, just as the build book try to say
)
12-05-2008, 10:11 PM
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Wicked build.... did you get the engine internals balanced? What about the balanceshaft delete kit, thought about that? It adds vibes, but they can be removed by balancing the engine internals.
12-08-2008, 12:00 PM
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Balance shafts have already being deleted, there's a pic of what's left of them + pushed rear bearings to block oil flow
Still not,
Working on the oil pressure and pump gears things.
Appeared to be untreated sintered metal, like commonly used on production parts like this one, but this is really really weak, especially with no treatment at all. We had the hardness analyzed on them and it was crap.
But well, leads to really cheap parts (here they are ~25€ so 30$, I guess they will be even much cheaper...) so worth trying adding some coating/hardening on these before having to buy GM racing ones
