15 replies to this topic

[holmesy]

just checking over my Mg metro engine ive just bought, ive taken the head off but forgot to measure the valve lift to check what cam is in it. ive been told it has a kent cam but which one is not known.

ive put a pushrod back in and checked a few of the lifts and have come back with some odd results

an average intake lift of 6.71mm or 0.264"
an average exhaust of 6.20mm or 0.244"

the intake i think is either standard metro or kent 266 since i was told it had a kent cam but the exhaust doesnt make any sense!!

any comments?

[jaydee]

Sounds like poor rockers or worn cam lobes or both.
Either the standard metro and the 266 have higher exhaust lift from intake lift, so i'd exclude both.

[Cooperman]

Sounds like a standard cam to me. The MG Metro and the 266 have a lift at the valves of 0.318" with the MG Metro and 0.320" with the 266 (that's from memory).

[holmesy]

after taking the chain cover off and seeing the duplex gear which looks very recent as well as the water pump I would believe that he was telling the truth about there being a Kent cam but I think it's just my dti gauge as its magnet is rubbish and doesn't hold it still. I worked it out with the 25% for the rocker gear then it was 0.330 for intake and 0.320 with exhaust thats at the valves

[jaydee]

No kent camshaft has more lift at the inlets afaik.
Maybe something more exotic, are you sure .330 is the inlet and not the exhaust?
Have fun:
Name Maker Int Lift inch Ex lift inch Valve lift 1.25 Int 1.25 Ex lift Lift 1.3 Int Lift 1.3 Ex Lift 1.5 Int Lift 1.5 Ex 850 Mini + Std Minor BMC 0.2 0.2 0.25 0.25 0.26 0.26 0.3 0.3 850/998 Metro Leyland 0.25 0.235 0.3125 0.29375 0.325 0.3055 0.375 0.3525 Cooper 998/ S/1100 midget BMC 0.25 0.25 0.3125 0.3125 0.325 0.325 0.375 0.375 1275 Metro + Turbo Leyland 0.25 0.25 0.3125 0.3125 0.325 0.325 0.375 0.375 CA1 Minisport 0.254331 0.254 0.317913 0.3175 0.33063 0.3302 0.381496 0.381 256 H/T MED 0.285 0.284 0.35625 0.355 0.3705 0.3692 0.4275 0.426 244/264 (From minimania) Elgin 0.262 0.262 0.3275 0.3275 0.3406 0.3406 0.393 0.393 SW5 Swiftune 0.281 0.281 0.35125 0.35125 0.3653 0.3653 0.4215 0.4215 SW5-07 Swiftune 0 0 0 0 0 0 VP1 APT HR255 (Cut by piper) Calver ST 0.288976 0.288976 0.36122 0.36122 0.375669 0.375669 0.433465 0.433465 MD256 Kent 0.262 0.262 0.3275 0.3275 0.3406 0.3406 0.393 0.393 BP255 Piper 0.281 0.281 0.35125 0.35125 0.3653 0.3653 0.4215 0.4215 CA2 Minisport 0.254331 0.254331 0.317913 0.317913 0.33063 0.33063 0.381496 0.381496 MSPD Fast road Morspeed 0.305 0.298 0.38125 0.3725 0.3965 0.3874 0.4575 0.447 Cooper S (510) BMC 0.25 0.25 0.3125 0.3125 0.325 0.325 0.375 0.375 250/264 (From minimania) Elgin 0.262 0.25 0.3275 0.3125 0.3406 0.325 0.393 0.375 260 Minisport 0.255 0.264 0.31875 0.33 0.3315 0.3432 0.3825 0.396 265 Mild rd/Turbo Minisport 0 0 0 0 0 0 APT266-MN APT 0.27 0.27 0.3375 0.3375 0.351 0.351 0.405 0.405 MD266 Kent 0.263 0.27 0.32875 0.3375 0.3419 0.351 0.3945 0.405 MD246 Kent 0.284646 0.284646 0.355807 0.355807 0.370039 0.370039 0.426969 0.426969 997 Cooper (948) BMC 0.25 0.25 0.3125 0.3125 0.325 0.325 0.375 0.375 MG/Vanden Plas Metro Leyland 0.25 0.25 0.3125 0.3125 0.325 0.325 0.375 0.375 262/268 (From minimania) Elgin 0.318 0.318 0.3975 0.3975 0.4134 0.4134 0.477 0.477

[jaydee]

Damn forum..how can i attach a table on here?

[bmcecosse]

Measuring 'lift' is not a good way to try to identify a cam! If it's a Kent cam it will likely have an ID mark on the end face.

[holmesy]

I don't want to take timing gear off as I just want to clean it up and check everything is okay

[holmesy]

back again and did a retest with the head on and rockers.

better answers this time but can't find the list I used with all the Kent cams profiles on it.

lift at the valves this time was 0.369inch(7.51mm) exhaust
0.354inch(7.21mm) inlet

but didn't set the tappet gap yet but there was a miniscule gap there though.

these figures sound better and recognisable to anyone??

[jaydee]

Those figures dont recall me any cam..
Email me i have the sheets though

[ACDodd]

Accuracy is key when measuring cams, Post up the lift at split overlap measured at the lobes, 1 & 2, i'll be able to tell you what the cams characteristics are.

AC

[holmesy]

what i forgot to do was set the tappet clearance so that might be an issue, have set the exhaust to 17thou and inlet to 14thou, is that correct for a 1989 mg metro?

ACDodd, how do you want me to measure the lift? i will be taking the measurements from the valves

regards Connor

[ACDodd]

http://www.kelseysho...product_id=2049

Measure the lift at the pushrods not the valves. You need 2 dial gauges and turn the engine until the reading on the dial gauges are equal. Quote that figure. See the article above for more info.

AC

[holmesy]

so I've got to take the rockers off then?

[ACDodd]

Rockers off, Yes.

AC