Seems to gel with what my old man always told me (a Diesel mechanic for 25+ years and counting).

http://www.mototuneusa.com/break_in_secrets.htm

What do the gurus here think?

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"Life is not like a box of chocolates... it's more like a jar of jalapenos. Whatever you do today, may burn your arse tomorrow."

I get the dreaded red screen for attempting access a banned site from a Govt computer

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

that was interesting
hmmmmmm
makka

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Anonymous moderation means the agro that is built up towards the mods isn't aimed at an individual (fewer "Makk" attacks). Less stress for mods means less moderator "retirements".

very interesting.

Sound like that way I ran My Mini engine in and no problems.

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I've Got One
You've Got One
We've All Got One
What Is It



A Bloody Mini

1970 Mini K, 1380cc, 1.75 HIF SU, 30 70 Cam, 2" Zorts
1969 Mini K, Stock Standard and Orginal. (Slow as Hell)

my mate used to build engines for bathurst minis in the 60's, he always said he ran them in the way they were raced - flat out. He'd put a motor in a car, drive it at 120mph to melbourne and back (from ballarat, about 100k's) and that was it run in. He said once he had a weber on a brand new motor suck the socks off the trumpets into the carb, and it stopped the motor dead at 100mph. All the oil spewed out of any orifice it could find, he filled it up with oil again and it was all good LOL.

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did I tell you that I won a trophy?

I asked about this when i was running my new engine in.
here's a couple of responses:

from usenet (alt.autos.mini): http://tinyurl.com/3okcu

from minimania (incl a response from DRMINI): http://tinyurl.com/4naxk

GeoffP

i dunno...
its just too revolutionary for me
ive been told to ask an engineer of 30 years when i brought that topic up
and the engineer will definitely tell me that thats was radical

and then again, who's been told to say and do that,
who's been there and can provide evidence that may or may not be credible?

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forever chasing clearer skies...

The guy also has some other interesting ideas as well. He fills in the inlet ports of modern jap bikes to increse intake velocity. 6-8% more power. Reckons flowbenching + port & polishing heads can rob power.

If you can put up with the annoying yank writing style and terrible colour scheme:

http://www.mototuneusa.com/think_fast_intake_porting.htm

Index of ariticles (he has a few on his porting techniques):

http://www.mototuneusa.com/thanx.htm

_________________
"Life is not like a box of chocolates... it's more like a jar of jalapenos. Whatever you do today, may burn your arse tomorrow."

A mate of mine bought an 1100S brand new and he believed in this method. We took it straight from dealer out to The Heathcote Road and flogged it up and down a few times. It was a bloody quick 1100S after that.

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Chris

Everything I like is either
illegal, immoral or fattening.

i like to take neutral stances:

1. why is everyone porting and polishing? the logical answer is to increase air/fuel mixture flow and reduce resistance

2. has anyone (else) tried to fill in the inlet holes to actually show an increase in power? sure it will increase velocity, but that means decreasing the volume (fluid mechanics) and less air/fuel

so im not yet convinced about that, 1. is superior

_________________
Inconspicuously Conspicuous
Appreciation without Depreciation
forever chasing clearer skies...

Go read the articles, he takes care of both of your issues.

The thing I like about his porting ideas is that it is (relatively) easy to verify the results of the changes, unlike the break in ideas.

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"Life is not like a box of chocolates... it's more like a jar of jalapenos. Whatever you do today, may burn your arse tomorrow."

does his theory vary according to the technology that went into the manufacture of the engine? I mean, you have OHC, DOHC, alloy heads, alloy blocks, cast iron heads, cast iron blocks, 4 cyl, 6cyl, 8cyl........a motor from the 60's is very different to a motor from the 90's. Do these factors make his theory complete garbage?

Who knows??.... but it was an interesting read.

Remember the Ferguson TEA20 tractor? Had the same basic motor as a Standard Vanguard, or Triumph TR2 back then. One big difference- the Vanguard had round inlet ports and the Fergie had 1/2 round ports.
Power- Vanguard ~68HP, Ferguson tractor ~28 HP.
OK so the carby was smaller etc.. but it's the principle that matters.
To make power you need to flow more air & fuel...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

a friend of mine didn't run his new 1275 in, and it went way fast, there was no explanation for it..
do u think this is true? and does it apply to our engines?

I don't want to start defending the articles, especially against the likes of the doc, but what he says does make sense, and he has graphs (and race results) to show his success. He also shows how the jap bike manufacturers HAVE been making ports smaller over the years, increasing power.

He's saying the flowbench does not acurately represent what happens in a running engine. Sure, increased flow rates improves charge volume for the suction part of the cycle, but there is more to it than that. Charge momentum effects also come into play.

I'm not sure how it would apply to a half-century old engine design, but I think the main point to take away is to use the scientific method. Don't port & polish, and change the cam at the same time. Do one at a time and be sure that it makes a positive difference.

Having said that, there are enough experts around who have tried an tested methods. It's cheaper and easier to leverage their knowledge. But if your in the position to test ideas, don't be boxed in to doing only what other people are doing.

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"Life is not like a box of chocolates... it's more like a jar of jalapenos. Whatever you do today, may burn your arse tomorrow."