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martin-reyland said:it's been a long time coming but my new engine is finished and on tuesday a couple of mates and myself bolted it onto harvey's dyno .
because this engine is not the same as your average cosworth yb (read unique or first yb of this spec anywhere!) and has had some some previously untried radical mods i decided to treat it's first dyno session as a running in and fault finding excercise but things went that well (no engine probs) that mapping was started and it at half ten last night we called it a day and because it was getting late and a mod needs doing to my ecu and also because i have a couple of other small mods i would like to do to the engine also the dyno has a couple of urgent engines that need to be mapped. so the engine will return to the dyno in a week or so to finish the mapping i will then rev the engine a further 1000rpm (or so!) as the power was still climbing at 7500rpmD: .
it's hard to put it into words but this engine is something else, it sounds unbelievably crisp and smooth... with just a sniff more boost or ignition added here or there and it just makes big clumps of power its hard to know when to stop!
no dyno graphs yet but i will give you the max power reading at 7500rpm... in just a mo
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734hp and 500ftlb uncorrected
702hp and 490ish torque corrected
oh and it makes full boost by 4000rpm..
HAVE THAT!
martin-reyland said:ok... for those interested.
from the off i decided i wanted an engine that would rev but still be quite responsive so rather than destroke the engine to get the rod length to stroke ratio right i decided to increase the stroke. now, when you stroke a yb you normally end up with a less than ideal ratio. what you need is a MUCH taller block enabling a longer stroke but also more importantly longer rods...... much longer rods! the millington engine had a 8mm taller block but even that is not ideal for what i wanted so i had to make my block taller. in simple terms i have added a spacer on top of a 200 block and then linered through both parts...ping, tall block! now all that seems simple but believe me it's not, there's a lot to consider!
for the moment here's what i want to reveal about the new donkey....
* it's more than 2200cc
* the rods are just under an inch longer than standard
* the crank has a longer stroke
* the bores are larger than standard and are nicosil coated
* the head has big ports, big valves, solid lifters and spunky cams
* the inlet manifold is made up from an m.i.s. mag plenum, jenvey individual throttle bodies and a jenvey manifold which had to be chopped and welded to get it under the bonnet!
* turbo spec is secret for now as 2 were tried and one was chosen
* the engine misses the bonnet by 5mm
* it has loads more potential for extra power
* the dyno figures are 100% accurate, some might claim more but reyland horses have always been strong!
any questions? (not you phil
p.s. can be arsed to spell check this so sorry for any mistakes, pictures will be uploaded tonight too!
