924Board.org

[Chrenan]

Weather permitting (which doesn't look good), I may have the car up and running this weekend with the fresh engine. Augidog sent me this a while ago:

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

In a nutshell, the procedure seems to be:

Load the engine by opening the throttle hard in 2nd, 3rd and 4th gear.

Alternate between short bursts of hard acceleration and deceleration. You don't have to go over 65 mph to properly load the rings.

The biggest problem with breaking your engine in on the street is if you get stuck in slow city traffic. For the first 200 miles or so, get out into the country where you can vary the speed more and run it through the gears !

Remember that both hard acceleration and hard engine braking (deceleration) are equally important during the break in process.

Any thoughts on engine break in? From guys I've talked to here, I've heard everything from rev the hell out of it, to don't go over 4500 rpm for the first 1000 miles, to break it in like you plan on driving it for the rest of its life. Any other tried and true methods I should know about, especially for that first run?
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1987 951 - M193 Version for Japan

[endwrench]

The advice you posted is very sound as far as I am concerned. I break in every engine I install the same way. It works. And as far as I am concerned it is pretty much broke in within the first hour. I don't recomend overloading a tightly built cast piston street engine after only an hour but anything built with any performance in mind is ready to go.

My 924 has cast pistons, cast rings and used bores. It has almost no blowby. Even now with the blower. I haven't even hooked up a catch can to the blowby tube yet! Nothing.

I did use the speed-pro ring gap though

Todd

[Paul]

I posted my procedure here:

http://www.924board.org/viewtopic.php?t=9821&highlight=engine+break
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

[Mike924]

Pretty much go along with Paul's advice plus remember to change the oil and filter after the 1000 mile run-in period.
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1985 Porsche 924 'Lux', Kalahari Beige (my ex)
1993 Porsche 968 Coupe, Midnight Blue, 6 spd

'There is no substitute for a little grease under your fingernails.' - Chrenan, 924board.org

[Chrenan]

Thanks for the tips guys.
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1987 951 - M193 Version for Japan

[doomer77]

ive heard that you should do anything but accelerate hard and fast! the key to breaking in an engine is taking it slow the first 1000 km and then let it rip, this will let the metal parts "get used" to eachother. hard accelerating in the beginning will cause unecessary stress on the engine and give it shorter life.

theres even a story to back this up,
my dad and my uncle, both being motorcycle freaks, bought very similar motorcycles at the same time. my uncle didnt care much for "breaking stuff in" and drove full throttle from the beginning, the result: he started having engine trouble very fast. my dad on the other hand took it easy in the beginning, resulting in a very soundly running bike.
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Why drink and drive when you can smoke and fly?
Carpe diem. and if that doesnt work; get drunk!

1980 924 n/a - engine swap begun
1989 Volvo 480ES

[chris24]

Yeah, yeah...you'll hear sad stories from both ways. I've tried both and had good results and bad results on both (on tractor engines...hardly porsches).

That doesn't help at all does it! Sorry.

Good luck!
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1983 - 924 (185K miles) - not mint
1985 - 924 (148K miles) - mint
1990 - 944S2 cab (52K miles)

[morghen]

i say:

fire it up in the morning...with oil and coolant and everything perfectly set.
keep it runing for 6-8 hours(at ~2000 RPM) without moving the car,monitor the temps and try to keep them at ~non-variable values. then do 1000 Kms under 3000 RPM...and you will have a perfectly healthy engine.

This is the way we do it around here.
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Supercharger and EFI kits
https://www.the924.com

[PORSCHEV]

All sounds good in theory...but! I have done alot of motors...and 50% of the time...even if you triple check all fitting hoses etc....you'll miss something and have to shut it down to do some minor repair. Sometimes the timing is off a bit....or a sensor isn't reading...could be anything. I plan for that stuff now
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1976 924
5 lug conversion, 17'C2 wheels,custom body work,327 vette engine.

1978-#53 "D" track racer.