Thanks for the tip DI.

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Love cruising in a bare metal Val!

Your engine sounds exactly like mine was. I had to run 100 octane just to drive it around and then 110 to race. I had another head ported to match the shaved one I had on the engine ans swapped it out. Car purrs like a kitten on crap 87. Looking into a cam swap and then the high compression head may go back on.

OK guys here is all the info from the engine builder.

Cyl Bore Diameter 3.46 in.
Eng Stroke 4.125 in.
Number of Cyl 6.
Combustion Chamber Volume 52 cc.
Piston Crown to Block Deck Face 0.080 in.
Piston Valve Relef Volumes 0 cc.
Compressed Gasket Thickness 0.040 in.
Gasket Average Bore Diameter 3.525 in.
Piston Dome Volume 0 cc.
Piston Dish Volume 0 cc.
Outside Diameter of the Piston at Top Land 3.428 in.
Dimension Piston Crown to Top Ring Groove 0.326 in.

Engine Capacity 3813.462 cc. or 232.712 ci.
Compression Ratio 9.8716:1

They used a "Columbus" Compression Ratio/Capacity Calculator.

Hope this helps in the analysis/discussion regarding cam selection, pinging issues, etc.

Thanks for the input guys - much appreciated.

Bare Metal Maz

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Love cruising in a bare metal Val!

Depending on the cam centerline...if he put it in at the recommended 4 degrees advanced setting per comp....your DCR is about 8.38:1 which isn't bad...but does require at least super unleaded on a short cam like that. Your next step would logically be to recurve the distributor before giving up and replacing the cam, but there will be a lot of give and take doing it.

-D.Idiot

Hi all. Update on the engine situation.

Have spoken to Dean Tighe at Tighe Cams, Brisbane. He has recommended their 104 grind for my setup. He's been very helpful and patient with me. I've sent a cam his way to be reground. Should have it back in a week and hopefuly in the car a week after that.

Also, got in touch with Eric Bolander (ebolander@pbm-erson.com) at Erson Cams. He recomended his TQ20M grind on the intake and TQ30M grind on the exhaust. Cam price was good but shipping to Aus was a little too pricey.

Anyway, fingers crossed!

_________________
Love cruising in a bare metal Val!

The relationship between camshaft duration and compression ratio is the best kept speed secret there is. In this case you have a higher compression ratio then you need for the camshaft duration you have. The Erson cam would be a huge step in the right direction.
don

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8 cylinders are for folks who cant make HP

Frustration... I suppose you have to patient with these things.

Picked up the 104 cam last week from Tighe, only to find that Dean indicated I would need to get the comp down. Aaaah! The whole point of getting a regrind was to keep the current setup. He has offered to take the cam back and regrind another stock cam. So, not all is lost...

Anyway, I'm installing an electronic ignition and getting it recurved next week to see if I can get on top of the pinging issues. Colder plugs and retune and who knows...

Do you think the The 104 cam (specs below), would be any better for my current set-up than the CC 264s? It has more duration but less lift.

Any help (encouragement...) at this time would be well appreciated.

Regards,

Bare Metal Maz
LIFT DUR. OPEN CLOSE AREA
Lobe I1 ----- ------ ----------- ----------- ------
Centerline 108 ATDC 0.004 316.83 43.6 BTDC 93.23 ABDC 21.78
Runout 0.0006 0.006 299.09 38.42 BTDC 80.67 ABDC 21.74
Lift @ TDC 0.0506 0.01 271.21 29.54 BTDC 61.68 ABDC 21.63
Valve Lash 0.01 0.012 263.31 25.93 BTDC 57.38 ABDC 21.59
Rocker Ratio 1.5 0.014 257.09 22.9 BTDC 54.19 ABDC 21.55
Lobe Separtion 109 0.016 252.21 20.4 BTDC 51.81 ABDC 21.51
Minimum Flat 0.018 248.01 18.19 BTDC 49.82 ABDC 21.48
Follower Dia. 0.8233 0.02 244.47 16.38 BTDC 48.09 ABDC 21.44
0.04 221 4.35 BTDC 36.66 ABDC 21.1
0.05 212.83 0.23 BTDC 32.59 ABDC 20.92
0.1 181.53 15.37 ATDC 16.9 ABDC 19.76
0.2 118.55 46.46 ATDC 15 BBDC 14.96
0.27849 --- PEAK CAM LIFT ---
0.40774 --- PEAK VALVE LIFT ---

LIFT DUR. OPEN CLOSE AREA
Lobe E1 ----- ------ ----------- ----------- ------
Centerline 110 BTDC 0.004 312.72 78.8 BBDC 53.92 ATDC 21.58
Runout 0.006 293.53 73.58 BBDC 39.95 ATDC 21.53
Lift @ TDC 0.0417 0.01 268.19 64.48 BBDC 23.71 ATDC 21.43
Valve Lash 0.012 0.012 261.06 60.74 BBDC 20.32 ATDC 21.39
Rocker Ratio 1.5 0.014 255.27 57.72 BBDC 17.55 ATDC 21.36
Lobe Separtion 109 0.016 250.49 55.17 BBDC 15.31 ATDC 21.32
Minimum Flat 0.018 246.5 53.04 BBDC 13.46 ATDC 21.29
Follower Dia. 0.8121 0.02 242.97 51.19 BBDC 11.77 ATDC 21.25
0.04 219.96 39.25 BBDC 0.71 ATDC 20.92
0.05 211.83 35.17 BBDC 3.35 BTDC 20.74
0.1 180.54 19.41 BBDC 18.87 BTDC 19.58
0.2 117.54 11.6 ABDC 50.86 BTDC 14.78
0.27713 --- PEAK CAM LIFT ---
0.4037 --- PEAK VALVE LIFT ---

_________________
Love cruising in a bare metal Val!

S6F,

Well I finally got round to getting the new electronic distributor recurved and installed with GM module (BIN024) upgrade. Plus installed colder spark plugs, a general tune and minor transmission linkage adjustment. The result - fantastic! No pinging. Better idle. Noticeably more power. The car just wants to pull and keep pulling! The carby is now the limiting factor (will get onto that next round of upgrades). Next on the list before summer is brakes & air-conditioning.

A big thank you to Barry @ Future Auto, Stafford and Geoff @ Peach Performance, Stafford for their expertise.

A big thank you to all the contributors (DI & co.) that have offered advice and encouragement. I really do appreciate it!

Looking forward to the next family cruise down south in October!

Bare Metal Maz

_________________
Love cruising in a bare metal Val!