Phyxius

This is a rod I drew up that will allow one to use VG30DETT pistons with a stock L28 crank. It is VERY beefy (heavy) and could probably handle over 1000hp at over 10000rpm. This would have to be machined out of a solid billet of steel. It has provisions for 3/8" or 10mm rod bolts. I plan on drawing a H-beam and a 'x beam' pauter-type rod. These will probably be a little more on the lighter side.

have you done any more with the heads?

I didnt even think about the surging. oops

Would it be possible to use multiple external wastegates, and a very small exhaust AR? In my mind, two or three wastegates would flow all of the exhaust that the turbo couldn't handle while the turbo would spool up much faster.

Would anyone be interested in having a set of forged rods that will bolt onto the L-series cranks and be long enough and have the right small ends for VG and SR pistons? I'm just tossing around the idea, and haven't really contacted anyone. Just gauging interest. I'm sure they'd be on par as far as cost goes with other forged rods...maybe we could get them cheaper if I do all the CAD work, or some of you know someone who can mill and heat treat them.

i *THINK* the mounts line up, and the tranny and drive train should hold up. You'll have to get a fuel injection pump for sure.

anyone know the approximate length of the intake ports in our heads?

Will the skyline manifolds fit in the car with the KA heads? I've never seen an RB in person, so i have no idea of the size of the manifolds and such. can you send me your cad files that you are working on? I'd like to take a look at them. Or at least the shape and spacing of the gaskets so i can work on some stuff myself. I'm not tryin to steal anything...we're all in this for the same reason...faster

You said you'd buy it for a 'full track' car. Not a street/strip car. From what I understand, more affects the air flow through a pipe than the final bend. A runner that goes straight from the plenum or throttle body to the port will be most efficient. If you wanted to use bends to equalize the airflow, you'd have to know the airflow through all the tubes, and then design it so that the ones with higher airflow have more or sharper bends to slow the flow down to the level of those with the lowest airflow. I have some engineering background, but that doesn't mean my word is the gospel. Take it as a grain of salt. Another idea struck me just now as to why this could be a mute point. The manifold isn't really our limiting factor. It's the heads. Maybe we should concentrate on them a little more. Of course if we made new heads whether they were 1.5 KA24 heads, an RB head, or a custom job, they would most likely need custom intake and exhaust manifolds....

That's for a track car though. We are talking about every day drivers here.

WOW! he wants $3300 for that kit. That's NUTS. You could custom build one for less than $500 probably. with ITBs and turbo, you'd certainly have to have some type of reverse header or airbox.

about the only way to ensure equal flow into all cylinders is to have individual throttle bodies and runners for each cylinder. Some manifold style intakes can come really close. The Z intake isn't that bad, and turbos work to even out the flow some (by providing even, positive pressure in the whole manifold). However, not perfectly by any means. Individual throttle bodies come with their own set of problems. Linkage to open and close them all exactly at the same time would probably be the hardest hurdle. It wouldnt be horrible......maybe....we should be trying to design something like this... should be ultra responsive. you'd still have to have all the air come through a air sensor of some sort...therefore you'd still have to have a plenum of some sort. Maybe something like a reverse header style intake would be better or...you could just have a mass air pressure type sensor hooked into all the runners.....interesting.... i'm rambling now...lol...i'll stop

I didn't mean to say they were immune, just meant to say they have a higher tolerance. I have a several hundred dollar engine simulator, and when you tell it the motor is turbo or supercharged, it throws intake manifold calculations 'out the window'. Correct me if i'm wrong, but when you tune a manifold, be it exhaust or intake, you are tuning it to maximize momentum in the air flow so that it will 'push' or 'pull' more air into or out of the cylinders at a certain rpm range while not choking the engine at other rpms. This 'pushing' creates positive pressure in the manifold in certain cases, while the 'pulling' of the exhaust creates a vacuum to suck more air out of the cylinders. From what I understand, you don't want the flow velocities to exceed mach 1, or a shock wave will form killing your flow. Ideally, low velocities in large diameter, short runners provide the most efficient flow but very low momentum at low rpm. This would be good for a high revving motor that needed all the power up top. A small diameter, long runner will build velocity, momentum, and power very quickly at low rpm, but will choke the motor at high rpm. The trick is finding the happy medium. There are calculators and things available to find the length and diameter of ideal runners for an engine, but they assume straight pipes with no bends. Bends reduce the momentum of the flow. Of course, I AM still a student, and I may be way off base. I'm fairly certain most of this is accurate.

For a turbo car, wave propigation isn't such a big deal. Just jam it in. There are calculators for the length and width of runners for NA cars. or are we talking about 2 different things? The composite thing is a good idea. Would have to make sure your resin was petro-resistant.

I'm an aerospace engineering student, and I just happen to work at our Engineering Research Center where we do CFD all day long. The model looks fairly simple, and I should be able to do it within a week depending on how clean the model is. (This is trying to work it in with my current work-related project.) How big is the file, and can you convert it to *.iges or *.igs? The only problem I can see is with the tubes. Without having them cast, or mandrel bent, to spec, they could be very hard to reproduce. Not trying to rain on your parade, just making some observations You could have them be straight from the plenum to the ports, but they would enter at strange angles which would cause some turbulent flow. The only other option I see is to make your bells smaller and have them spaced so they are able to go straight in the ports. Again, this won't be as good as your current design as far as flow goes.

I'm new to the board, and wanted to say hi here before I posted anywhere else. I have a daily driven '79 zx with a l28et that's slightly modded. It has some rust problems, especially with one frame rail. It also needs to be stripped to the metal and repainted. For that reason, I have a '81 zxt t-top with a buggered up motor that I'm working on. It needs a paint job and a new interior, but has almost NO rust. The undercarriage is amazingly clean. As soon as the '81 is back in good condition, it will probably get the '79's rebuilt turbo motor. That is unless I can sell the 79 and get enough to buy an RB motor.