I've got a head from a 1275 spi mini and I'm hoping to use it on a 1275 that will be running carbs. Anybody know if this will be a straight forward bolt on? I was also wondering if it is possible, will the SPI head give less power than an equivilent 1275 head designed for carbs and if so, why? I think the casting is 12G940... but I could be wrong.
Spi Head On Carb Car?
Started by
scars
, Apr 29 2009 06:43 AM
3 replies to this topic
#2
MRA
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Posted 29 April 2009 - 07:21 AM
castings are the same, valves are dependant on which model of SPI its off........... Cooper etc
Has it been modified ? I currently run larger inlet and exhaust ported and chambered to what some people would call a ST3 condition...... well that's on my 1330 SPI Cooper it didn't come off an SPI originally....
in other words, there are things to look out for, but most 12G940 castings are interchangeable, the exceptions to this are ones that have been modded for a very high or low compression ratio, too high and it may lead to detonation, too low, and you will lose a lot of potential BHP.
The simple question is did the SPI head come off a naturally aspirated (non turbo or supercharged) engine ? if it did, then you stand a very good chance that it will work with your engine
Has it been modified ? I currently run larger inlet and exhaust ported and chambered to what some people would call a ST3 condition...... well that's on my 1330 SPI Cooper it didn't come off an SPI originally....
in other words, there are things to look out for, but most 12G940 castings are interchangeable, the exceptions to this are ones that have been modded for a very high or low compression ratio, too high and it may lead to detonation, too low, and you will lose a lot of potential BHP.
The simple question is did the SPI head come off a naturally aspirated (non turbo or supercharged) engine ? if it did, then you stand a very good chance that it will work with your engine
#3
scars
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Mini Mad
Posted 29 April 2009 - 12:59 PM
castings are the same, valves are dependant on which model of SPI its off........... Cooper etc
Has it been modified ? I currently run larger inlet and exhaust ported and chambered to what some people would call a ST3 condition...... well that's on my 1330 SPI Cooper it didn't come off an SPI originally....
in other words, there are things to look out for, but most 12G940 castings are interchangeable, the exceptions to this are ones that have been modded for a very high or low compression ratio, too high and it may lead to detonation, too low, and you will lose a lot of potential BHP.
The simple question is did the SPI head come off a naturally aspirated (non turbo or supercharged) engine ? if it did, then you stand a very good chance that it will work with your engine
Thanks for the quick reply, it's a great help. It came from a standard 94 Cooper.
#4
mini_mad69
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Let future you worry about it
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Posted 29 April 2009 - 01:13 PM
You will probably have to drill and tap the temp sender hole, and maybe the heater take-off if your going to use it.
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