thehelix112

So I tell this to a mate, and he says: ``I saw that over a year ago, some guy had 3d cad and cfd results.'' So needless to say I asked (very politely) mind you, for the link. http://forums.evolutionm.net/archive/index.php/t-196546.html Obviously that design is somewhat limited (large pressure drop across plenums), but definitely worth the read. Dave

Ok let me break it down M = weight of car A = how fast car is accelerating F = forward force acting on car, and a direct translation of torque produced by the engine and tyre traction. Let us first off assume tyre traction is perfect (slip ratio = 0), and let us also assume the same engine is being used, thus F is the same. If you change M, all you are changing is A. It sounds like you're talking about M `magically' affecting F without a change in A. Show me how that works? Dave

Sorry I didn't see that you posted specs on the areas. I would have to guess that you've got enough room in there to account for more boundary layer losses in area. I would say though, can't really tell that well from the pics, but I'd try to get the slot to extend so that it covers each runner inlet the same. Ie, it looks like it doesn't cover the start of #1 or the end of #6. Great idea btw, I was initially skeptical but it makes sense, I think. If I'm thinking about it correctly, the air will slow down in the pre-plenum, thus converting the majority of its dynamic pressure to static pressure. Because this air is going slower, any pressure `holes' will have time to be filled before the air slides through the gap and into the main plenum and onwards to the engine. If you build this, please install pressure gauges in both plenums, I would love to see that plot. Dave

Making the exhaust bigger at the back than at the front has very, very, very little benefit. The only benefit I can think of is reduced drag under load because of the larger area of positive pressure feeding into the large `vacuum' at the back of the car. Probably not worth the extra weight. Dave

2x2.5 represents a 22% loss in cross sectional area over a single 4", more if you add in the boundary layer factors. I say keep the 4" as long as you can, then transition to oval for ground clearance. Dave

Unless the 1000lb car accelerates 10 times as fast as the other car, which I think may have been X64v's point. There is a reason transmissions are rated in torque. Assuming that 100% of the torque is used (and not lost in say, tyre slip > 1), both cars will pop the transmission at the same time. Dave

Its early, but I think 1mm shave and 2mm gasket will be the same as running a 1mm gasket with no shave. The things you're concerned with are the height of the cam towers, as it affects timing, and not altering the shape of the chamber (too much). Its called 0.020" because the measurement is in thousanths of an inch. 0.020" = `20 thou'. 0.02" = `2 hundreths', which doesn't sound anywhere near as cool. Dave

I would be interested to see the CFD analysis. I would have to assume that its important to ensure that the cross sectional area of the slit it atleast as big as that of the inlet pipe. Maybe even a little bigger to allow for more boundary layer loss due to increased circumference. Do you have a mesh generated for it? If turbobluestreak (or anyone else) makes one to do CFD, I'd love a copy so I can have a play. Started mucking with this: http://caelinux.com Dave Dave

Did I miss a post where you went back to the dyno? Or are you going with the well-worn net-boy's guide to dyno figure inflation? I would have to question what sort of driveline you're running if you're going to claim 25% loss, or have you since had the engine on an engine dyno to support that claim. Forgive me for asking, just well, you know, seeing as you don't seem willing to believe anyone else has made hp without proof? Dave

Clinton (as per usual) is right on the money. You can run whatever turbo setup you want on a stock setup as long as you have the supporting mods to run it correctly. I have a GT35R on a stock block, have run 19psi, with no mechanical issues. If you can afford to control the spark and fuel correctly, but whatever turbo meets your wildest HP requirements. I would say a 500hp GT30 would go over nicely. Still internally gated so simpler to install too. Dave

Careless, The engine is the VR38DETT, not a VQ anything. Dave

Why not? Because you can't close the bonnet. Because your powerband is < 100rpm. Because its no longer a functional tool, its a piece of installation art. Happily installed anywhere a dyno and fanboys are present. Etc, Dave

Apples and oranges. VR != VQ (heres hoping they made it closed deck). Anything >3L, twin turbo, and not made out of wood is a potential power house. I also hope they didn't let the Renault gingerbeers anywhere near the damn thing. Mikelly, I don't see any previous mention of the L prior to your post? Dave

Nice work Bryan, that is an impressive figure any which way you slice it. Add to that the lack of time, tuning, and small turbos, I'd say it has a lot more potential left in it. Forgive the late question, did you sleeve the block at all? N42 block or F54? Dave

Waiting for the results still? Dave

Looking good Jon.

Dynojet's are inertial? Haha.. no wonder they suck so hard. Dave

To be honest, it doesn't make a lick of difference to me, I get bored with Nissan Sport magazine within 10 seconds. Thoughts go along these lines: ``rice, rice, rice, stock-with-exhaust, rice, why am i reading this again, bin.'' Maybe if you had some actual technical features, were doing something approaching your own research/work (instead of scrounging off internet forums *coughwindtunneltestresultscough*), you'd have a more compelling and interesting magazine. Dave

As a matter of interest Rob, what make of dyno are you using? Those are impressive numbers any which way really. Dave

I think its a pretty well accepted fact that 12.5:1 is ideal conditions for max power in petroleum powered internal combustion engines (all other things being equal). Dave

My apologies. I stand corrected. Dave

Tidy work there Yasin. I like that inlet manifold. Dave

Austin, What I would be more concerned with is that you have now made the engine a fully stressed member of the front suspension. When the outside front applies a force to turn the car, it pushes on the frame, which pushes on the mount, which pushes on the engine. And its an alu block I think? Dave

That looks damn good Jon. I like how the `point' of the door bar, which I would have to guess is the point that will absorb the most energy is directly where the driver is. Do you have any more detail/follow up on your door gutting thread? Dave