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Post by bedbug on Aug 30, 2014 8:53:13 GMT
The old 101 lump is practically dead. Compressions examples at 105 90 68 and 35! It has the highest Hi-ratio transfer set yet still runs around easily at 65MPH all day. I think the removal of the exhaust back pressure has permitted that. So it's time to build a new one  The block from my rangie 4.6 went to Turners and was top hatted. It has o rings at the bottom of the liners too. Even if the block well and truly starts to leak it's now, it's a wet liner install. It should be the end of the problem. The 4.6 had a very high running temp up nearer the 100's. Given the different expansion rates and the lack of remaining Ally after the CC increase liner slip and block porosity was always a risk. I visited a turners and Richard showed me inside a block via a core plug hole with an LED the issues it faces . It was a real insight. There's so little meat round the head studs I'm surprised they don't pull out. I think if you get one that doesn't leak now, and run it down near the 80's you probably won't ever see the liner and porosity problem occur. The expansion is less, the coolant pressure is less. It's Just my opinion, you could well be right, if you chose to differ. So the 1st thing on my list is to find the CC of my heads and then decide what to do. I think they have been skimmed a fair bit and I have my doubts about what's left, to be open a out it. The block at the moment is sitting with 4.0 Pistons in. Once I've got the head data today, I can crunch that with the static compression calculator. |
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Post by bedbug on Aug 30, 2014 22:05:35 GMT
After faffing around with the Burette and the breather hole in the Perspex plate I got some decent repeatable numbers. Chamber volumes that range from 26cc - 28cc. I had no idea they would be that far out. I expect variations in the installed heights of the valves caused by wear is affecting the chamber volumes. I need to sort out the valves and seats before the final head numbers can be attained.
Max lift on standard rocker gear is .461, the Torque max is 0.50 under that.
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Post by garrycol on Sept 24, 2014 15:38:16 GMT
While I do have 4.6 low comp pistons for my 4.6 build I also have 4.0 low comp pistons. My rough calcs show that by using the 4.0 pistons in the 4.6 the comp ratio should be around 9.3:1 - a good compromise between low and high comp and might still be able to use low RON fuel.
The 4.0 and 4.6 pistons use different gudgeons - same length and diameter but the 4.6 have a thicker wall for extra strength. I moved the 4.6 gudgeons across to the 4.0 pistons.
Garry
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Post by bedbug on Sept 25, 2014 20:19:59 GMT
That piston sounds good. |
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Post by bedbug on Jan 11, 2015 9:37:10 GMT
To date
Heads:-
Skimmed back to the limit.
Using the datum blocks at each end to determine the head thickness to start with. What I did was to tell the machinist what thickness these had to end up at. Doing it this way any previous skims are included in your sums too and the heads are more likely to end up level on the machine bed in relation to the chambers . Both of my heads chambers volumes got smaller from end to the other, indicating they may not have been placed flat on the machine bed in relation to the chambers previously.
Bigger Valves and Seats
Larger valves accommodated by simply opening up the existing seats.
3 angle seat job at the same time, if they can't do is you've got the wrong machinist - walk out.
Installed valve height asked for after recutting seats was the original Rover 4.6 Spec. 47.63mm. Handed over valves to machinist.
Guides
Bullet nosed guides installed which are all cut back at the top to facilitate a larger cam lift later, may be.
Springs
The valve springs installed at present are just cut down rocker shaft springs. as I still need to bolt the heads down and rotate the whole engine to check the clearance between the heads / valves and Pistons. The weak little springs make it easier to rotate the engine by hand and allow you to move the valves down manually at anytime in the rotation with your hand. However if the lifter plunger spring can't overcome the lighter valve spring then your true clearance is no longer going to be true.
Standard springs caps and retainers will be used in the final build.
Porting !
I was told if I went to open up the ports down by the valves I may just find trouble and I did. I opened up the ports a small amount where the seat inserts are held in and narrow the port apertures down. In doing so I found casting imperfections at the casting seams which you can see in this area before you start. So the heads had to be welded up here and the porting done again. For the extra power released in comparison to running the heads back and forth for welding. I wouldn't bother with this " feature " again.
Chamber CC'ing
Final numbers not known yet but I will be adjusting them to be within 0.5CC. The importance of is for my build is to ensure 1 pot doesn't detonate ahead of the rest. Forcing me to retard my ignition at the expense of the other 7 pots .
Camshaft
This is a piper torque max. I started to install this and found that I need the Cam retainer plate from a serp 3.9 engine if I want to be sure the cam stays in its place. Three reasons for doing this a) stops any noise of the cam slapping again the block face if it moves back and forth but more importantly b) I'm using a distributor, any camshaft end float would be. reflected in a change of spark timing . I'm seeing this as a possible cause of detonation or pinking and I'm keen to keen to run as much advance as I can for economy on light load. c) I don't want the csm chain and sprockets I bought to have any wear caused by side load.
Elusive Cam retainer plate part no ERR5926
Timing Chain and gears
Piper true roller and adjustable camshaft gear.
Woodruff key Standard
Dizzy gear Standard
Front cover and oil pump - retained from the 101.
The block
Turner Top Hat with O' rings at the bottom. Rules out any future liner shift causing an issue.
Drilled two Oil drain holes from the valley area into the Timing chain area- you can google this for more detail its a common thing.
Looking at fitting
a) a splash plate over the lifter to help stop hot oil causing heat migration up into the base of the inlet manifold.
b) a custom windage tray to help stop oil aeration and windage drag.
Crank Standard
Rods Standard
Bolts
Bar the JED head stud kit. Eales apparently has never had a gasket go whilst using his studs. So I'm not overly bothered about the additional hustle they may cause getting a head off in the 101.
Inlet manifold changed these out to suit the manifold.
Alternator mounting bolt has to be larger due to one 10 bolt head hole being made larger thread.
Exhaust manifold bolts - ARP ( Real Steal ). Smaller head size works well will modified P38 Manifolds.
I'm not balancing the rotating assembly as Its only got new standard Pistons and the RPM is not enough to upset the crank.
I'm not lightening because off road this will just make recovering from wheel spin in mud or on ice more difficult. .
Sump, The ally Thor sump is being replaced with one from a serp 3.9
Distributor Mallory But with a magnetic pickup as this version has 36 degrees advance whilst all the optical Ones are only 24 degrees max advance.
Carb is an Edelbrock 500CFM on an Edelbrock Manifold with a plenum we will custom produce.
Fuel pump, 101 pump designed to feed 2psi to Strombergs !
Replacing with an external Land Rover pump and ditching the return pipe.
Gear linkage will be remade totally from the Gearbox up to the knob.
Steve
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The block from my rangie 4.6 went to Turners and was top hatted. It has o rings at the bottom of the liners too. Even if the block well and truly starts to leak it's now, it's a wet liner install. It should be the end of the problem. The 4.6 had a very high running temp up nearer the 100's. Given the different expansion rates and the lack of remaining Ally after the CC increase liner slip and block porosity was always a risk. I visited a turners and Richard showed me inside a block via a core plug hole with an LED the issues it faces . It was a real insight. There's so little meat round the head studs I'm surprised they don't pull out. I think if you get one that doesn't leak now, and run it down near the 80's you probably won't ever see the liner and porosity problem occur. The expansion is less, the coolant pressure is less. It's Just my opinion, you could well be right, if you chose to differ. 