radiaki11

[QUOTE=WishIHadaSilvia;4558648]Regas on a 240:









for some reason that car is one the cleaniest 240's "iv'e seen" its just a real simple car and that how i like my car's built very nice car in my opinion .

Fabrik8

That thing sure could use the right size tires.

all4sr's

yeah....so we're definatly thinking its a wiring issue....cause the car is fine now and has been for the last 2 days.....wierd

Fabrik8

That's right in line with most of the swap wiring I've seen. It runs, but it's unreliable enough to ever have full confidence in. This is why wiring is one of the most important, and often most overlooked aspects of doing an engine swap, and why people that don't have any experience should stay away from it. You can have the best, most perfect fitting swap in the world, and if the wiring isn't top notch then all you have is an unreliable garage filler.

Spindrift

Don't just assume it's fine now as it will come back to bite you in the ass again if you don't fix it.

Like I said it's very simple wiring and shouldn't take you more than 15 minutes to find your issue if that's where it lies.

edit: If your wiring isn't soldered i'd start there, butt connectors/twisting wires together and taping them off with electrical tape will NOT suffice and will eventually give you shit connections.

all4sr's

i appreciate the info guys....we'll will be working on the car this sunday and hopefully getting everything straigh....well, i plan on it, seeing as this is more than likely gonna be my car in the very near future

Trey

One thing to keep in mind is that SR20 heads are one of the industries tightest tolerance heads made. The shims that ride on the valve tips come in thicknesses that vary in ".001. That means that the acceptable range is just ".0005. This is important once you realize that the cam pushes on the rocker arm and the arm pushes on 2 valves. If the valves are at different heights, then the rocker is at an angle, which wears on the cam/ruins it/causes extra friction. This might not even be the problem but it is a flaw in the design of the SR20. If this ends up being why the car is starting to break down then pm me and we will take it one step further and give you a shim height that is just ".0002 or less. It is much better for the motor.

Fabrik8

Why would the tolerance be half the shim height increment? It's impossible to get within the tolerance then, because unless there is another area for adjustment than it isn't able to be achieved. The closest you would be able to get is 0.001 or less, but without any other adjustment that's the best you can get. So all the valves would be somewhere between 0.000 and 0.001, with no ability to match them closer than that without sub-0.001 shims available.

Is the tolerance you're talking about measured at the cam, meaning that the rocker ratio must be exactly 2:1? I've never played with SR20 shims before, I'm confused..


*EDIT*
I found the answer. It's 0.14 to 0.17 mm clearance at the cam, which is 0.00056 to 0.00067 inches. So that makes sense now, because the rocker ratio is listed as 1.43:1, so a 0.001 shim can give a change of 0.00069, so you have to be better than that because you can get somewhere less than 0.001 (at the valve) with the shims.

So the 0.0005" clearance is a completely arbitrary number and has nothing to do with the shim height, because the rocker ratio isn't 2:1.
I understand now.