Catch can, ECU, EGR and Accusump.

[Mr_Sparkle]

First off, Hi from New Zealand.

Now for some background information.

Over the last 10 years, I built have a circuit racing S14 Silvia, which I campaign in local events. The SR20DET is a wee bit boring, so I have decided to do a VH45DE and Z32 5spd swap.

I purchased a 6/1993 - 11/1993 VH45DE (Engine number 880XX) This must have been one of the first 1994 spec VH45DEs because, it has the 16bit ECU, non-siamese inlet ports, studded head for rocker cover, new style injectors, and metal backed chain guides (although the left bank slack side tensioner guide has had the plastic separate from the metal and has come away).

Anyway. I am wondering the best way to run an oil catch can without getting positive crank case pressure.

Now before anyone suggests that I run the factory PCV, this is not possible for a couple of reasons. Firstly Class requirements require me to run some sort of catch tank. Secondly, the previous owner did not include any of the PCV equipment with the engine. Another factor although not relevant at the present time is that it will eventually be running ITBs with out a plenum.

In the immediate future, I intend to get an 8 bit ECU, and chip it / Nistune it. When I do the ITBs, cams etc, I will likely go for a Link G4 Extreme (Links are easy to get tuned here in New Zealand).

Are the pinouts the same on the 8 bit and 16 bit ECUs (I can only find pinouts for the 16 bit ones).

With regards to the EGR, the previous owner also did not include that. I was wondering if any of the guys who have played with Niztunes and other chipped factory ECUs would happen to know if it is easy to disable the ECU's requirement for the EGR.

With regards to the Accusump, I was wondering which size one would be adequate. My car pulls 1.8Gs on warm slicks on certain corners, so some sort of surge protection will probably be required. Are there any issues with the extra oil required for use with the Accusump? What is the best way of adding the Accusump? I was thinking the sandwich plate method would be nice and easy (because we don't do huge numbers of consecutive laps I haven't needed to run an oil cooler on the SR20 as yet). Are there sandwich plates available for VH45s or are there other ones which are compatible?

Any help would be appreciated.

Cheers,

Paul.

[Mr_Sparkle]

Any one able to help? Or point me in the right direction?

[nismo silvia]

Just run all of the vc breathers to a catch can and you can get one that feeds back into the oil pan if you want but it is not nessesary since its na and there shouldn't be a ton of blowby, the oil I doubt would be a problem but if you want to spend money you can get a drysump, the egr just plug the intake manifold and you should have headers so no problem there. you should check out mazworx.com that is the place to get the stuff for a vh.

Any one able to help? Or point me in the right direction?

[Mr_Sparkle]

Thanks for the reply.

With the catch can, what is the best way to keep positive crank case pressure to a minimum / have pressure below atmospheric?

For my budget, dry sumping it won't give a big enough gain per $ spent, hence the accusump, which will provide insurance against oil starvation as oil moves away from the pickup under high g-forces. Regarding that, I am wondering which size one would be best, and which method people whore are running them are using them for plumbing them in.

With regards to the EGR, blocking it off isnt an issue, however I understand the ECU will throw a code and light up the check engine light which I would like to have function normally, so I was wondering if I could disable the ECU's requirement of a functioning EGR.

And finally are the 8bit and 16 bit ECU pinouts the same or similar? or does anyone have a pinout for the 8bit EXU (there only appear to be 16bit pinouts on the NICO FSM pages).

Cheers,

Paul.

[Carl H]

8bit ecu is a direct retrofit to the 16bit harness, as far as egr...ecu does not care if it is connected or not, it will not set a code for it.

[nismo silvia]

I don't think you will have a problem with possitive possitive pressure and I have not had a problem with g's and oil as long as the oil is at the correct level lol

[hannibal]

Wouldnt an oil cooler be a good idea?

[Mr_Sparkle]

Cheers for the replies guys.

At the moment the car is only being used for time attack / dual car formats which is 3 hot laps. The tracks are only between 3 and 4 km long and lap times are in the 1min 20sec - 2min range, add to that a reasonably big radiator so the oil currently does not get too hot (although the same may not run true for the vh). After reading GS14Racer's thoughts that the -10 fitting size may have contributed to the death of his engine, I want to be careful with any modifications to the oiling system.

[nismo silvia]

I have not seen a link to that do you have it?

Cheers for the replies guys.

At the moment the car is only being used for time attack / dual car formats which is 3 hot laps. The tracks are only between 3 and 4 km long and lap times are in the 1min 20sec - 2min range, add to that a reasonably big radiator so the oil currently does not get too hot (although the same may not run true for the vh). After reading GS14Racer's thoughts that the -10 fitting size may have contributed to the death of his engine, I want to be careful with any modifications to the oiling system.

[Mr_Sparkle]

It was a thread about designing and machining sandwich plates for VH45 on here, Ill see if i can find it.



EDIT: Found it:

vh-oil-block-for-filter-relocation-t438 ... 0#p4923914

[Mr_Sparkle]

After much more reading and talking to an engineer, I have more or less figured out how I will do the catch can setup. I figured I'd share it for anyone else that has a similar requirement.

Out of the rocker covers, the lines will go to a catch tank with an internal oil separator (to separate as much oil vapour from the crank case gas as possible). From the catch tank, one line will come out the bottom and connect back to the sump (to drain any oil caught back into the sump). From the top of the catch can, two lines will run to the exhaust (one in each header). They will be connected to the header via a pipe nipple and check valve (welded at a 45 degree angle pointing towards the rear of the car). This will provide constant vacuum to relieve any positive crankcase pressure.

All of this will hopefully keep it running with the same effect as the factory system (although no oil vapour in the intake), and allow for class rules.