r33_racer

GTRNUR has experience with this from his open deck engine. When I last looked at doing it, the best way seems to be a standard headgasket with the copper O rings. You get the awesome sealing for water and oil from the standard gasket as it can take up the most irregularity in flatness and the O ring seals the cylinders near perfectly. Otherwise next best would be your MLS with the copper O rings. You could PM GTRNUR and ask for his advice.

If its using oil when on the throttle it generally wont be valve guides or seals, that generally only happens at idle and on decel. Oil burning under load is usually always rings. Could be wrong cross hatch angle, damaged rings, scratches in bore from improper assembly or dirty assembly, poor initial break in and the list goes on. Have you done the leak down test yet?

Basically as T04GTR stated. You can get whatever finish you want with it, it just costs more to get it as it equals more machine time. You can go from super rough to mirror finish if desired. Alot of people who see the finish on the ports think that it isnt any good and sometimes get the extra time spent to smooth it out and rough it up by hand or leave it smooth, but in fact its just right as is. The machined lines left are actually beneficial in helping increase air speed through the ports. As the air passes over the these lines, the ridges create mini vortices which help give the air direction and a small amount of turbulence which helps keep fuel atomised and in suspension. Now the increase in air speed comes about by the breaking up of the boundary layer that exists between the outer most layer of air and the actual port surface. Because air is viscous, when it makes contact with the port walls the friction generated actually slows it down. Essentially, air, as it enters the port is fastest through the centre and it slows down as the layers get closer and closer to the port walls. Does that make sense? I believe this trick was actually disovered accidentally but its now quite common on cnc'd heads. But everyone has different ideas on these things, some people think its good while others still believe in the more original port finishes. So the finish some people think to be poor and possibly because of the machines limitations really cant be further from the truth.

There are reasons why the cnc finish is how it is. Its not the machines limitations by any means.

Mahles are good. Though last I heard from ACL distributor Nasons they were moving to China for manufacturing, dunno if thats happened yet. Ross are good. Slightly heavier, though a tougher piston but you need more piston to bore clearance for them which results in abit of piston slap when cold but no big deal. The Ross's come with a better ring package then most; thicker rings. For the power level your chasing a set of Spool rods will handle it all and more just fine if you dont want to stick with the prepped stock rod route. Very cost effective when comparing to other brands too.

Been busy with the race car all week. We took it out for testing last Sunday and the gearbox broke. Reverse gear and dog ring busted. Put a crack in the housing. So been working on that. In some of my free time at work Ive machined up the V band ring for the dump pipe. Took me about 2.5 hrs of lathe time to get it done, what a PITA. Im hoping to get that last runner on the manifold done this weekend so I can start welding it all up! Hopefully Ill have more to show after the weekend.

Why thanks mate! Its getting there slowly. This manifold is probably the most time consuming part of the build. Well if nitrous was allowed on the street, or easily hidden then I may have considered it. But I do have the methanol injection system I will be hooking up to spray into the supercharger inlet and before the throttle body to help keep the charge temps down. I wasnt planning on doing any kind of vent mainly because I dont really want to cut up the bonnet. I still have alot to do really. I just want this to all be finished and working so I can enjoy my car damnit!

30 psi is about normal for warm idle. Oil pressure is always high when cold. The gauge shouldn't ever read nothing when tge car is running. Is the gauge electric or mechanical?

Manifold will get ceramic coated, then wrapped. Then as much acl heat shielding around it to keep the heat of everything. Its going to be difficult thats for sure.

I have been flat out working on the race car since last weekend. But inbetween I've managed to get a few more done. Heres where I am at so far. Just one more runner to go Just need a few more 45's and 90's and then it will be done!

Heres our RB30DET in the race car.

You normally need a pretty good surface finish to use a mls headgasket. Probably 40RA or finer. Usually with alloy heads/cast iron blocks and mls headgaskets, the finer the finish the better. If you arent getting your head faced, then probably best to not use your mls gasket. GTRNUR will probably confirm this. After all his development work on his open deck stroker build he would be an expert in this area!

If the paper said 80ft/lbs then thats cool. Unless you used the higher torque from the next grade of studs... Either way I cant see it being an issue. You probably should pull the head and then clean the gasket and apply hylomar to it and retorque it down. As GTRNUR said, hymolar is fantastic stuff. I've reused the same headgasket three times without any issues

Yeh it will look great. The lobster backs always look good.

Just out of curiosity, how come you torqued them to 80ft/lbs and not 72ft/lbs as per ARP spec?

Excellent work! Looks the shit. Are you going to Tig all the joints up? or Mig it?

Thats strange, normally you get oil in the coolant as oil pressure is always greater then cooling system pressure.

If my car is going and all good by then im in for sure and will hopefully cruise down with the SAU QLD blokes

I tried just cleaning them initially, but found the mill scale was causing issues. So ive just been blasting everything first which made it all alot nicer when welding. No gaps in the fittings when im aligning them. All butted up hard to eachother and just welding inside the two beveled edges. But I understand where you are coming from there. Thanks for the tips as I dont usually do that much pipe work.

R31Nismoid is right in that its more application/motor setup specific. That last post I was being quite negative about it and didnt quite explain everything properly. Ill try to do it now as best as i can. The usual rule is fine if your revs are kept to around standard. When you start going high with them, say 7000rpm and upwards you generally need higher pressures. This is due to the poor design of the nissan cranks oiling system. The crankshaft utilises cross drilled mains and big ends inorder to feed oil to the rods. With this design, as the revs climb so does the centrifugal force which acts against the oil. I think I read somewhere that this force starts to have an impact on the oil feed once you get over 5000-6000rpm. What happens is the oil starts to seperate and froth/foam up inside the crank as oil pressure is trying to send it to the big end, but the centrifugal force is trying to send it back to the main journal. Since pump manufacturers needs to cover bases for all setups in one hit they make the pump capable of the worst case scenario. I can only assume thats why Nitto have two springs, one for 70psi and the other for 120psi. Now if you are building a wild high reving engine, then you would need the higher spring pressure to make sure you have more oil pressure then centrifugal force acting against it so your big ends dont suffer oil starvation. The unfortunate part of a cross drilled crank is that the only way to overcome that force is by increased oil pressure. The ideal crank oil system is a straight shoot gallery. You can find this on pretty well any v8 crankshaft. Its just one hole that goes from your main journal to the big end journal and with this style you dont need big oil pressure as it doesnt have anywhere near as much centrifugal force acting against it. But everything plays a part in oiling system setup, main and big end clearances, conrod side clearance, oil viscosity choice and oil hole sizes in your block and crankshaft. There are probably more variables that make an impact on this setup too that I havent listed. Now the obvious drawbacks are what I spelled out last time in that post ages ago. However, in the perfect setup, everything would be worked out so you would only run just the right amount of oil pressure for your setup(revs, clearances blah blah) and nothing would be in excess so you have minimal negatives/losses. Hopefully that makes enough sense and anyone with a better understanding please feel free to clarify any of my errors

Thanks Michael. They sound tough! Check out youtube. Stocky McStock did it in his vl. Im pretty sure he has a video up.

Yeh im loving it too. Its all abit new to me and its been interesting working it all out. I appreciate the offer...maybe you should move to the flooding state so that could happen next time OKBANANA, mate it is my road car so it will defs be doing that. Im looking forward to it. Hows your build going?

Yeh you pull the gears out and leave the backing plate off. Just need to bung off the pressure outlet side of the pump so its not open to atmosphere through the block to where the oil filter screws on. Unless you use one of those external oil filter adaptor plate setups and just put a bung in the outlet section of it where it would usually go to the oil filter. Hopefully that makes sense lol.

External oil pick up direct from sump then either go into external oil filter/cooler setup and then direct into the block where filter screws onto.

Thanks. Funny you should mention that as thats what I was about to do today at work, weld two small strips of angle to the ends of a set of vice grips so I could clamp it properly. I was also thinking about machinging some bungs and putting nipples in the ends and purging the pipes but I couldnt be arsed. Ive just been sand blasting all the pieces inside and out then cleaning with acetone, hence why they all look dull grey have no mill scale on them anywhere. I am tig welding all of it, its alot neater. I am actually a fabricator by trade