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Discussion Starter #1
whats the max a 1.5qv will rev to?? just so ill be able to set up a rev limiter for just before it goes pop :lol:
 

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Thats great, hahaha
get someone else to red line there car, then when they write back on here that there engine popped, you will know not to go that high :cheese::cheese::cheese:

heee heeee i like it :)
 

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When I had my 33 1,5 TI on the rolling road he reved it to 7600 rpm. There is no reason to take it that high for normal use. It had max power at 6350 rpm but it had almost the same hp up until 7100-7200 rpm.
 

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Discussion Starter #11
i know the manin power will be between 5/7 but i was hoping to set a limiter about 8:wow:
or is that just gonna kill it :cry:
 

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That stacks up with the info I got with my race engine kit (unbuilt CK Alfa Challenge unit), which was that it would rev to 9000 rpm.

But it really depends where you peak power is - no point in holding it much past that as the engine is going off the boil.

The Alfa boxer is a very well balanced unit straight out of the box. Ultra-short 3-bearing crank doesn't suffer from crankshaft "whip", the main bearings are 4-bolt for extra bottom end strength and the big end caps are serrated. Plus oversquare pistons and double valve springs in the top end all add to the rev-happy nature. The only downside from the tuning point of view is the heron head (combustion chamber formed by the dished piston top), which is easy to manufacture but difficult to gas flow. Larger capacity boxers (1.7) went to flat-top pistons though.

I would agree 7-7.5k seems like a good limit for a mildly modified engine. I say "seems like" because I have never strayed beyond 6000 in normal road use :D

Lauren
 

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I was told by a well respected race engine builder a few years ago that a well balanced boxer engine could rev to 9000rpm, but every 1000rpm extra over 6000 would increase the wear rate by a factor of 10.
If 9000 revs were used frequently, the engine life may be less than 100 miles.
On my tuned 8v hillclimb engine I used to rev to approx 7250 but it was pretty worn after about 5000 miles.
No gain without pain!!
Mark
 

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Boxer engine is capable of reaching 9000 without any mechanical problem. But..... You have to have the engine tuned for that purpose which means correct timing , extra fuel feed to the engine and an overall good status. The only problem has to do with timing and fuel. Here in some Tech School have boxer engines that , for testing purposes, rev the engines up to 13000 / 140000 rpm in order to create problem to them in order to fix them.

John , for 10 years was constantly revving his 1.5 engine up to 8000 rpms and more and with over 200.000 klm but his engine was fine tuned and it lasted another 150.000 klm before replacing it with 1.7.
 

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My rev limiter is set to 8750rpm, it will go to 9500rpm, as Adie Hawkins set it so it would improve longevity and the insure that its used quite a lot. Think I have done around 20k miles on it now, but it require oil changes every 1000miles!!!!!!!!!!!!!!!!!!!!!!!!!!!!.
 

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Using a motor at such high revolutions requires constant checks on the engine and in very short time to service it, but..........it's worth it. :) Very few engines can tollerate such abuse, but boxer engines are superb, even with the setbacks that they have due to the fact that the pistons are parallel to the ground.
 
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