Gsxr1127 engine with DOT head

[wraith]

Thinking about putting a DOT head on a 1127 good or bad?

[DAZ]

@fatblokeonbandit did it on a 1200 , believe he got a dyno'd 130+ bhp out of it 

Edit : have you got a bit of room above the carbs as the dot head raises the carbs slightly due to the angle of the intake ports ? I believe the shortstroke 750 slingshots used shorter rubbers to help alleviate this 

Edited May 30 by DAZ
Addition

[wraith]

33 minutes ago, DAZ said:

@fatblokeonbandit did it on a 1200 , believe he got a dyno'd 130+ bhp out of it 

Edit : have you got a bit of room above the carbs as the dot head raises the carbs slightly due to the angle of the intake ports ? I believe the shortstroke 750 slingshots used shorter rubbers to help alleviate this 

I've also done/got a b12 engine with a DOT head and gsxr cams with 38mm gsxr 750 carbs and is well worth doing on the bandit lump. My thinking on a gsxr1100 engine is, as the gsxr already has a higher comp because of the positions will the higher comp gsxr pistons course a problem with the DOT. Clearance etc?

[DAZ]

21 minutes ago, wraith said:

I've also done/got a b12 engine with a DOT head and gsxr cams with 38mm gsxr 750 carbs and is well worth doing on the bandit lump. My thinking on a gsxr1100 engine is, as the gsxr already has a higher comp because of the positions will the higher comp gsxr pistons course a problem with the DOT. Clearance etc?

Bumped a thread called what's a dot for you , says comp should end up around 11.5:1 similar to a 1216 kit , as for clearance only real way would be to dry build and clay it 

[clivegto]

I put a flowed dot head on a gsxr 1052cc motor and it was well worth the effort 

[wraith]

56 minutes ago, clivegto said:

I put a flowed dot head on a gsxr 1052cc motor and it was well worth the effort 

Did it go straight on like they do on the b12 or was extra work needed?

 

[Duckndive]

The dot head has a smaller chamber and same size valves + the inlet port is raised "can cause carb tank issues" 

You need to do the sums ...but Rule of thumb Stock Dot Head on Stock 1100 raise's CR by One Point ... 

[wraith]

41 minutes ago, Duckndive said:

The dot head has a smaller chamber and same size valves + the inlet port is raised "can cause carb tank issues" 

You need to do the sums ...but Rule of thumb Stock Dot Head on Stock 1100 raise's CR by One Point ... 

So the DOT head will fit straight on to the gsxr1127 ?

Will be running standard gsxr1100k cams.

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I've got a DOT ported head on my gsx1157et (b12 engine) and that want straight on but had to raise the take slightly but it's also running the gsxr 38mm carbs that are tailor than the 36mm carbs.

[Duckndive]

2 hours ago, wraith said:

So the DOT head will fit straight on to the gsxr1127 ?

A very misused statement IMO 

measuring the bits and doing the sums will give you the CR  and remember to use 1100 cam sprockets ... 

you should do a dry build with all the parts you are using and check valve to piston clearance   

[clivegto]

Yes the dot head bolted straight onto the 1052 motor even used a secondhand head gasket just sprayed it with primer like FB said to do. 

[baldrick]

Aren't the gsxr cam journals line bored? 

No experience of the swap but would wonder if that might cause a issue 

[clivegto]

21 minutes ago, baldrick said:

Aren't the gsxr cam journals line bored? 

No experience of the swap but would wonder if that might cause a issue 

Yes they are just use the cam caps that belong to the cylinder head but there is a way round this as well 

[Gixer1460]

25 minutes ago, baldrick said:

Aren't the gsxr cam journals line bored? 

No experience of the swap but would wonder if that might cause a issue 

Not an issue - its a cam swap not a cap swap. If it was no one could change cams to performance ones!