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1400 heads on a 1600 faq

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so i recently bought a NOS 1400 short block and a nos 1600 short block.

i tryed the 1400 head gasket on the 1600 and its a no go. for the following reasons

 

head studs on 1400(dual port wet sleeve) are a layed out diffently then on the 1600 also the bore is alot smaller on the 1400 so you would have to use the 1600 gasket(duh) problem is the water jacket on the head would be very close to the cylinder bore on the engine.

 

 

problems and fixes

 

water jacket miss alingment

i believe the water jackets could be ported to work

although they would still be very close to the bore and might not last long before blowing head gaskets

 

head studs not the same. i belive the head stud holes in the heads could be elongated to work,

you would also need to swap the head studs from the fourteen hundered to the 1600 since they are differnt lengthes

 

 

 

things that havent been covered,

 

cam differnces

compresion ratio change

intake fitment

push rod length differnces (if someone can measure the 1600 ones i can do the 1400.

 

anyway will try to add pix when i get a chance

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I have succesfully fitted 1400 heads to a 1600, you need to weld up the outside of the head and remachine the water jacket. overlay the headgasket on the head and you will see where, as for the headstuds i had no problems they lined up ok. Dimension the manifold will fit ok, and use the 1400 cam.

Cheers Thierry

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Hi. I have also successfully put 1400 GSR heads on an EA71. The studs and pattern were fine, the only problem I came across was some of the water gallery outlets in the heads. I had the heads welded and the outlets angled further outwards from the cylinder liners and had no problems. I also had a bead of weld added around the edge of the heads to better fit the crankcase. A light skim to level everything, and that's it. Just remember to re-torque the heads after about 15 minutes running.

Another problem is the compression ratio. My compression tester showed approx 195psi per cylinder which is a bit on the high side. I am in the process of doing a full rebuild after about 12 years and have skimmed 1/16th off the pistons, which the engineers tell me should be fine :eek:, to lower the compression a little. I'll let you know how I go.

Edited by howpow

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huh wonder what is wrong with my setup. ill have to check again and get back to you. i assume your both running the early 1600 with the external water crossover. ? i tryed on the newer 1600. anyway ill check again.:confused:

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Im been thinking of doing this on my GSR for quite a while....

 

Out of interest how did it preform compaired to the Standard 1400 GSR engine?

What was fuel economy like?

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Hi tailgatewagon. Yes it is an early EA71 with the external water crossover,

 

Kiwi subbie. I have a 40mm DCN Weber carby which was running a bit rich so economy was not great, about 11 litres per 100 klm. Performance wise it was great, just felt like a bigger GSR motor.

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The fastest i seen on my gsr with that motor was 115mph, i ended up selling the car. the guy cleaned the carbs and saw 118mph, as for economy i was getting high 30's mpg average and that was with the gsr twin carbs with standard jetting

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