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Thread: VET build Pics.

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Posts: 211-220 of 222
2011-08-24 08:48:21
Nice looks $$$$$ lol.
2011-08-24 09:07:49
yeah what does one of those cost. Im assuming you have to get longer upper oil pan bolts for that one or are they supplied with it? Looks very very stout.
2011-08-24 09:15:13
1100 $aud
2011-08-24 09:23:53
yeah, found it now. Looks really nice. Not really all that necessary but its definitely a nice piece. The factory girdle is pretty stout and does the job of tieing in all the main caps. Hell mazworx is using the factory girdle and crank on their s15 to well over 1300whp and no issues with bottom end breaking.
2011-08-25 10:57:17
these are also machined up here locally in Australia

one day ill build one of these with a P12 sr20v head and dry sump

2011-08-25 12:48:00
oh My Gawd
2011-08-25 13:47:36
Originally Posted by STR8E180
this is what u call a girdle
company here in Australia machines these out of billet

Really, a block girdle that integrates into the engine skirt really should have it's own name.
2011-08-28 13:41:34
? is the log type manifold that restricted on the vvl head or does it become restrictive on all det heads once u go above a certain hp level
2011-08-28 15:03:39
it affects a Ve head more especially because of the cams , it will also become a restriction on a det head with really big cams after a certain hp level where flow will start to hurt top end power.
2011-08-28 16:10:47
A friend of mine had a C5 Z06 corvette. He had a rear-mount twin turbo setup on it, with small turbos. But he used a huge NA cam because he loved the sound of the lopey idle. He figured a huge cam would make him more power.

After the build was done, we took it to the dyno where it made 460whp on 8psi. for a big engine, this power number was pathetic. Considering the cost of the build, and making less power than some of the NA guys, I had given him my input.

I told him to change cams, or get some bigger turbos and everything should work out. He kinda did both. He got huge exhaust housings on the same turbos, and put in a milder NA cam. He then made over 900whp and runs 9s consistently in the 1/4 mile.

The VE cams are huge, and not necessarily in just duration. But if you want to get a good idea of how large they are, put some 20w50 oil it it and flip the cams on at idle. The lopey idle is SO rough, the car won't even run. Keeping the idle at 1000rpm you should hear the lope, and it is far worse than S4 cams.

I remember having fun with some friends and kicking the vvl at low rpm and listen to how crazy the lope was. It sounds totally bad ass. But 48* overlap is huge overlap, 20* more than the S4 cams.

The log manifold can work with a VVL. But your results on a DE would likely be a lot better. A DE motor with the same setup and S4 cams will perform better.

To really take advantage of the flow of the VVL head, you must let it breathe. Since the motor is designed for NA, why not take the approach of treating like it is NA? This means taking a look at pressure differentials of intake and exhaust pressures on the NA VE, and getting as close to that ratio on a turbo VE.

If you measure backpressure on the VE engine when NA, you notice that the backpressure is just a little higher than intake pressure at high rpm past peak VE. Take a turbo VE and do the same thing, and you are likely having a lot more pressure on the exhaust than intake. If you are able to get the exhaust pressure down, while maintaining good positive pressure on the intake, you will see huge gains.

Case in point, Miko posted a dyno of his friends car making huge power on low boost on 20V cams. It is all about getting the exhaust side to take advantage of the flow. Too much backpressure and you are unable to scavenge the cylinders properly during that overlap period. Can you still make power? Sure, absolutely! But are you making the most of the engine?

The VE engine will always love big turbos. It does perform similarly to some honda engines. We can take some notes out of their camp and apply them to this engine. You would be amazed how many turbo builds are using NA cams, but they always utilize a free-flowing setup to make good power.

Getting boost pressure higher than backpressure is called crossover. Unity is a term used when volumetric efficiency is at or over 100%. When crossover happens, overunity is often experienced and large gains can be seen. Although, this typically can make the setup very sluggish in response. But sometimes, you can see improved response.

Having unity means having 100% volumetric efficiency, and if you ever plot out your VE on a turbo map, you can see that having a higher VE puts you in a different part of the map. Usually, you are able to utilize a more efficient part of the compressor on lower pressure ratio, with higher adiabatic efficiency, and increase the rate at which the turbo spools.

Imagine the same scenario, with a plugged up exhaust with higher backpressure. As VE drops, you experience a more sluggish turbo that spools later, and that lower VE also results in high pumping losses, and less power.

Solution? Free-flowing turbine, or treat the motor like a turbo motor and get turbo cams. Turbo cams are built to perform under circumstances of higher backpressure. They close the valves in a way to minimize overlap. In these circumstances, you see higher VE with a restrictive exhaust, because you are still able to promote a clean air-charge without reversion or an EGR effect.

If you really want to build a SR20VE, take advantage of its flow over the DE engine. Build, take measurements, log data, and keep the exhaust flowing with the stock cams. Then your power goals will come to fruition.

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