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In VSB14 any modification that increases power more than 20% must be approved by a VASS signatory, this is where it gets expensive, I'll be registering my car as a 6.0L which was optional in 1989.
The car has to meet emission standards for the year it was complianced here so 1990 for me. But we do not have annual Road worthy inspections in the state I live and emission testing is not part of a RW even if needed.
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Damn what kind of government treats people like that??
every time i think we got it bad, i just look around the rest of the world.
i have NEVER met anyone who died from NOX,?,WTF!!
back old days ,YES some were found dead from Carbon Monoxide, in closed garages.
Don't pity us too much in Australia. Whilst not perfect govt legislation has helped retain beautiful beaches and landscapes, excellent recreational fishing, near smog free cities, a very low gun related murder rate and a very high standard of living.
The USA introduced emission regulations to the world and its a good thing in my mind. In Australia most modified cars can pass emission testing with a sensible tune and cats. There are many modified 600hp plus cars here that are emission compliant.
Where I spend most of my time, in venezuela there are no enforced vehicle regulations and 4wds drive around on tractor wheels, some cars have fart pipes exhausts the could wake the dead, not so nice. The barrel of a dilapidated cement mixer truck fell off and killed a family of 5 stopped at the lights next to the truck. Some regulations are needed. Of course I wish the ones that apply to me were looser��
Originally Posted by ronbros
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Damn what kind of government treats people like that??
every time i think we got it bad, i just look around the rest of the world.
i have NEVER met anyone who died from NOX,?,WTF!!
back old days ,YES some were found dead from Carbon Monoxide, in closed garages.
Picked the heads up yesterday. Intake seats have 5 angle and exhaust 3 with backcut on the intake valve. The exhaust guides were also cut back to improve flow.
I had some time on the weekend, so I started on ccing the chambers. I had issues with repeatability in my readings, I was getting 0.5cc difference between readings. I found the spark plugs held 0.2cc and the vasaline I was using to seal everything was dissolving. Once I switched to grease and blew the chamber with air between measurements me repeatability was better than 0.1cc.
Hi Warren, the heads look great. I guess you have more than a few hours in those. Has the engine coming along? You must be getting excited now�� Cheers John.
It's a slow process ATM, I went back to work full time so time is now limited. The cams are away to be re-ground, there were a few marks in the lobes, problem is it's a 6hr round trip for me go and pick them up.
I've probably got at least 50hrs in the heads and another 10hrs at least to get the chambers all the same size. I have done the first one and it took me nearly 2hrs of grinding then checking the cc.
Warren are you getting the cams reground to stock specs or something else? Whatever you do you are making more progress than me. I’m still in Venezuela but was in Houston last week and got to see my 6L crank and go to a Jag car show. A couple of weeks ago I was taken to a car workshop in Venezuela where they restore and modify cars for wealthy Venezuelans. Often basketball and baseball players playing in the US. Beautiful work and labour at $1 per hour (75% of workers here earn $10 -was). A shame I won’t be here long enough to get a car done.
Cams will be ground stock, I'm not after peak power. I did toy with the idea of a little more lift and duration but after discussing with Norm settled on a stock cam, although the grind will be 5.3L not 6.0L, The difference is the 6.0L has a slower ramp.
after some doing some research on the Jag V12 factory cams, it seems that the 5.3L Pre-HE flat head cam has the best potential for performance and hi-RPM power.
the later HE was deffinately redesigned for better MPG.
and the Ford 6.0L cam for smooth/quiet operation,along with reduced fuel consumption.
Ford already knew that V12 engines were not going to be the norm for everyday driving, one of there reasons for dropping manufacture was cost and to many moving parts/internal friction!
I discussed this in length with Norman Lutz before I decided what way to go, and his answer was all Jaguar cams V12 and I6 use the same timing and all V12 cams use the same lift. The ROM does actually say that the 6.0L cams had a slower ramp.
The difference in V12 cams was in the ramp profile only. This does slow the opening of the valves.
BUT, Crow cams who are re-grinding my cams did all of Norms cams meaning their profile is for the pre-HE with the fastest ramp so I might be in luck.
Jaguar Specified a lighter oil grade stating in 1993, this may be why they reduced the hydraulic intensity of the cams so they could run a lighter oil safely with out loosing a lobe.
Increased cam timing is not as important and most people make it out to be. The head and the fluid dynamics of the port and valve is far more important. Usually if you run a "Bigger" cam you can gain some power, maybe... but frequently engine are over cam'd So drivability and torque suffer greatly. If you can improve the head flow, especially at low lift, power gains will be tremendous.
In the early 90's computer modeling programs started being widely used to design the intake ports. This fluid modeling software allowed engineers to discover ways to increase flow significantly yet cam timing was reduced for improved emissions. One example if this was when GM switched the L98 for the LT1 in the 1993 Corvette. Even tough the camshaft had 5 degrees less cam duration it made 60 more HP and about the same amount of torque despite a far inferior intake manifold. The switch to a simpler 1 piece intake was far easier to manufacture.
Another example... When comparing a Modern LS port to a 60's era Hemi port visually you would see the LS port "Looks" restrictive and the Hemi port with it's huge 2.25 inch valve "Looks" like it flows much better. In reality the LS port flows more over a much wider range of operating conditions and therefore is better in every way despite being smaller.
It does say in the ROM that the cam ramp was changed to reduce valve train noise.
The 6.0L also had tighter tolerance bearings which is why the Jaguar specified lighter grade oil.
I'm 100% with you on the big cams. I spent a LOT of hours de-shrouding the intake valve to improve low lift flow. In the HE head ( and that includes the 6.0L) the intake valve is recessed into the head about 4mm, this shrouds the intake valve significantly until about 1/2 lift.
The HE chamber is not ideal especially having the spark plug offset from the middle of the chamber, not much I can do about this, although I will be looking for longer spark plugs to see if I can get the plug further towards the centre.
I was reading a very good article about cams by David Vizzard and he was adamant that LSA (Lobe Separation Angle) was THE most important spec for a camshaft and duration should be set by LSA. The LSA for the V12 cam is 111° which is not ideal for the 5.3L this is why the 5.3L is a little lacking in lowend power.
I have also kept my intake ports small. Interestingly the pic I posted of the machined chamber a few posts ago has HUGE valves (intake are actually LS1) and small ports 37mm IIRC and made 620hp @7500rpm that's over 100hp/L
07-05-2017, 08:05 PM
