when you install a set of aftermarket forged pistons in an engine, do you have to let it get to normally opperating temp before driving? dont get me wrong, when i turn my car on in the morning, i let it idle for a bit to get some oil flowing before i drive anywhere. but iv heard when you get forged pistons, they will "chatter" if their cold before they expand when the engine reaches normall operating temperatures..
can anyone elaberate on this? i know theres plenty of people with forged pistons on the org.
also, what kind of break in process should i use when my engine is done? eagle rods andwhatever pistons i end up going with? do forged internals require a different break in process as a normal engine? or should i just take it easy for the 1st 1000 miles and not beat on it?
13 psi and climbing......
you should always let a engine with forged pistons warm up properly before drving. they expand more then normal pistons do because the forged material is denser. as for the break-in it should be the same more or less as any other engine. that is more of a function of the rings & cylinder walls then the pistons themselves. just make sure to do low load at low and high rpm when dooing break in not just low load / low rpm.
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hey bud,
i am running fully forged internals and i have not noticed any noticeable noise although the above statements are true, forged pistons take longer to expand. alot is determined with how much piston to wall clearence you go with. i have seen many people go with to much clearence and have a knock when the engine is cold. but as long as you let the engine warm to operating temp before you mash on it, you will be fine. as for the break in process, i went with about 1500 miles before i really mashed on it. however a big thing that is important that i am a firm believer in is the fallowing: when you start your fresh engine run it for about 100 miles or so and change the oil. when you assemble and engine you use assembly lubricants and alot of times you will get these lubes mixed in with the oil and also you will get some bearing material in the oil from the bearing breaking in themselves. it is a very good idea to change it shortly after you first start it. remeber whatever you do to break it in with a good oil, not synthetic. my brother is a mechanical engineer for GM and has built many high performance engines and he also recomends that you use a 30 weight oil for the first 100 mile break in or initial start up period. the reasoning behind this is because the first time an engine is started, oil is not everywhere that it needs to be right away... it will also help so that you get immediate oil pressure on start up since the oil is thicker and its a good idea because it gives that extra lubricant to bearing and other parts. good luck man, i cant wait till im turboed next spring, im tired of seeing my boost guage peek at 8 or 9 psi......15 psi is on the way...haha
Now I was told by a guy who builds race/street engines and built motors for hondas/ecotecs/VW's so on, and the such around here who will be building mine that what he does is once the motor is in and up to temp they run it on the dyno, through all the gears, to redline and then he said they are fine for abuse, he's been doing it this way for years and never a problem
opinions?
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Ask 100 engine builders for their break in procedure, and you'll get 100 different answers. The vast majority that i've seen posts by, or talked to in person, do seem to agree on keeping it under 3K and varying load, but they all have different quirks and additions to the procedures. I would play it safe and do it Bill's way, as i have heard several engine builder use similar guidelines to break in. I've never heard of breaking in an engine by running it right up to redline in every gear though... It may end up alright but i wouldn't want to prove/disprove it with my own personal engine.
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yeah 100 answers is about right
most small block chevy's ive done , after the cam break in , setting idle speed , adjusting the carb and timing , i change the oil , then drive it lightly for about a hour or 2 , change the oil again , then its redline city , if its gonna break its gonna do it then , then change the oil at 500 miles then 1000 miles , then every 3500 to 4000 after that , depending on street use and drag strip use
ive gotten alot of years outta motors doing them that way
but alot of it has to do with machine work as well as the quaility(brands) of parts you are using
best is to talk to the manufacture of the parts , and then the person doing your machine work , and go with their recomendations , as well as common sense , and you should be good to go
Bill Hahn Jr. wrote:Daniel Ksiazkiewicz wrote:however a big thing that is important that i am a firm believer in is the fallowing: when you start your fresh engine run it for about 100 miles or so and change the oil. when you assemble and engine you use assembly lubricants and alot of times you will get these lubes mixed in with the oil and also you will get some bearing material in the oil from the bearing breaking in themselves. it is a very good idea to change it shortly after you first start it.
I agree. This is a good idea because a significant amount of bearing material that shears off during break-in will come loose in the first couple of hours of operation. What's most critical,however, is that even if you wait until 1000 miles (frankly, if I am in a hurry, I'll shorten it to 500), you MUST get that metal-laden oil out of the engine before you put her under full load and high RPM.
On my motor we fired it up for the first time and held it at 3000rpm for about 15 minutes to break in the new valve train. Then i changed the oil before i even drove it around because lots assembly lube can clog up the oil filter. I also stick the wastegate eide open for the first 500 miles or so but still pushed the motor fairly hard to help the piston rings break in right.
- 93 mph in the 1/8 mile
Member of J-Body Of Michigan.
thanks for the answers. its obvious not to do anything when the engine is ice cold. i just wasnt sure if it needed to be at normal temp before you even drove it.. i dont want to due damage to the pistons or cylinder walls.
13 psi and climbing......
every engine builder in town has told me that if you're building an engine for boost, it's a good idea to break it in with boost.
anyone else have any feedback on that?
that way the rings are setting into the walls with the same amount of force its going to be seeing everyday
At the machine shop I worked, any new military engine were going on the dyno twice when brand new before being ship.
But like said above, if you want to build the engine once and keep it running for 100 000miles, be easy on it. If you don't care about rebuilding it after 20 000miles, get some soft rings and beat the crap out of it after 250 miles.
Gilles
2.3 Ho
stevefire wrote:every engine builder in town has told me that if you're building an engine for boost, it's a good idea to break it in with boost.
anyone else have any feedback on that?
that way the rings are setting into the walls with the same amount of force its going to be seeing everyday
thats what I say and the engine builder bulding mine, break it in how it's gonna be driven (boost no boost wise)
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