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Alternate Cylinder Head for MGA

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Alternate Cylinder Head for MGA
#1
  This topic is about my 1958 MG MGA 1500
TC108 Avatar
TC108 Aroon S
Durban, South Africa   ZAF
Hi, I have recently purchased a 1958 MGA 1500 as a project car. The engine came separately.
I am trying to rebuild the engine. The cylinder head was discovered as cracked when tested.
I have been given what seems to be a Wolseley cylinder head by a friend. I noticed that the holes on the inlet (perhaps called the inlet port) where the manifold connects, is smaller than the MGA head.
Also the valves are smaller than the standard MGA valves. I measured these to be 35mm intake and 30.2mm exhaust. These point to the Wolseley 1500 Engine with the following details:

Type: Btype
Motor Construction Year: 1957 -1965
Number of cylinders: 4
Bore ΓΈ: 73,02 mm
Engine content: 1489 CC
Compression ratio: 8,3 : 1
HP: 56

I am concerned that this head will give me lower than normal performance on the MGA.
Will it be restored to normal 72HP if I fit the larger MGA valves and have the head ported to the same size as the MGA?
I see that the compression ratio is the same as MGA.
Need some expert advice.
Any help appreciated.
Thanks
Aroon

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ghnl Avatar
ghnl Eric Russell
Mebane, North Carolina, USA   USA
1961 MG MGA "Calvin"
You would probably be better off finding an early MGB head. It will already have the right size valves and better porting. The combustion chamber volumes did vary among the various models. If you find a good head with the larger volume, you could have the head skimmed to reduce the volume. But be sure to have any replacement head checked for cracks before investing time & money in it.

see: http://mgaguru.com/mgtech/engine/ch100.htm



Eric Russell ~ Mebane, NC
1961 MGA #61, 1981 Alfa Romeo GTV6, 1984 Alfa Romeo Spider, 1991 Honda ST1100

Redhawk1689 Avatar
Redhawk1689 Gold Member Steven Stockham
Salina, Kansas, USA   USA
1958 MG MGA 1500 "Belle"
I'm not certain that a 1500 block works with an 1800 (MGB) head.

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Judge Jeffs Avatar
Judge Jeffs Gold Member Bill Jeffries
Chichester, West Sussex, UK   GBR
1959 MG MGA
The wolseley 1500 head took a single carb and as you say smaller valves and would not be a workable fit.
The Riley 1.5 had the same head as the 1500 MGA and also a 1600 or 1622 MGA head would fit. They would be your best bet if you can find one in SA.
Bill.

ghnl Avatar
ghnl Eric Russell
Mebane, North Carolina, USA   USA
1961 MG MGA "Calvin"
In reply to # 3494952 by Redhawk1689 I'm not certain that a 1500 block works with an 1800 (MGB) head.

It can. Some combinations might need valve relief pockets milled into the block's deck.

see: http://www.mgaguru.com/mgtech/power/cm202a.htm



Eric Russell ~ Mebane, NC
1961 MGA #61, 1981 Alfa Romeo GTV6, 1984 Alfa Romeo Spider, 1991 Honda ST1100

ozieagle Avatar
ozieagle Gold Member Herb Adler
Geelong Victoria, Australia   AUS
1958 Wolseley 1500 "Wooly"
1966 MG MGB "Bl**dy B"
Coming from a slightly different perspective...

My 1958 Wolseley 1500 turned out to have a 12H 1326 MGB head, with appropriate rockers fitted. The 1500 rocker assembly came separately.

The big issue for me was compression ratio. Standard was 7.2:1, with 38 cc combustion chamber. The 12H 1326 head has a 43cc CC. Calculated CR was around 6.8:1. I had the head shaved by 80 thou, which was the limit, before the valves started hitting the block. Theoretical CR is now about 7.9:1.

The re-builder fitted a 1622 head gasket, which seemed to have problems sealing between cylinders. I fitted an MGB gasket. Engine now runs well (it did before too), but seems to have a bit more grunt and less noise.

Herb



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Blueosprey90 Avatar
Blueosprey90 Jeff Sienkiewicz
New Milford, CT, USA   USA
You might also try to look for a Datsun / Nissan head from that era.

No personal knowledge, but from my own searches for a 15 head, I understand that the heads that fit are from the "E" and "J" series engines. They bolt right on but you need to port them and put in bigger valves to get good performance.


http://mgaguru.com/mgtech/engine/ch100b.htm



"Will it be restored to normal 72HP if I fit the larger MGA valves and have the head ported to the same size as the MGA?"

You can try porting the intake and exhaust ports. It will take hours and hours based on my experience. And pray that you don't have a void in the metal.

Look for the porting details in the MGA Special Tuning pamphlet. It is on Barney's site somewhere.

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TC108 Avatar
TC108 Aroon S
Durban, South Africa   ZAF
Many thanks to all who contributes. It is appreciated. The advice will be explored further with the help of a good machine shop.
Thanks

ozieagle Avatar
ozieagle Gold Member Herb Adler
Geelong Victoria, Australia   AUS
1958 Wolseley 1500 "Wooly"
1966 MG MGB "Bl**dy B"
In reply to # 3496021 by Blueosprey90 You might also try to look for a Datsun / Nissan head from that era.

No personal knowledge, but from my own searches for a 15 head, I understand that the heads that fit are from the "E" and "J" series engines. They bolt right on but you need to port them and put in bigger valves to get good performance.


http://mgaguru.com/mgtech/engine/ch100b.htm



"Will it be restored to normal 72HP if I fit the larger MGA valves and have the head ported to the same size as the MGA?"

You can try porting the intake and exhaust ports. It will take hours and hours based on my experience. And pray that you don't have a void in the metal.

Look for the porting details in the MGA Special Tuning pamphlet. It is on Barney's site somewhere.

If you are considering the Datsun route, why not do those mods to the Wolseley head?

For your info, the Wolseley head P/N is 11G311.

Herb



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