Just did compression test pissssed!!!!!

[2GFWDbeast]

Had a shop do my engine build for me. They told me not to do any hard driving for at least 500 miles. So far i only have 199 miles on it, and its been about a month. I decided to do a compression test and it was 160 128 130 160 cause i noticed my vacuum at idle was little on the low side.

I have Je pistons 9.5:1. My vacuum is at 8 in/hg at idle. I do have hks 272 cams. Could it be that piston 2 and 3 haven't seated yet or do i need to goto the shop and bi*** at them, cause they messed something up.

 

[sidewaystsi]

Seriously!?Does no one own a frickin haynes manual anymore!? . Direct quote from the haynes ''Accelerate at full throttle from 30 to 50 mph, then allow vehicle to slow to 30 mph with the throttle closed. Repeat the procedure 10 to 12 times. This will load the piston rings and cause them to seat properly against the cylinder walls." Roddin the engine in the beginning to seat the rings is not some new magic procedure.

 

[99vipereater]

i don't see the reason to change the oil so many times. The motor was cleaned and what not. And if there was metal shavings in the oil i be able to see it on the dip stick. Iv seen it on previous cars. My oil is as clean and clear as water rite now at almost 230 miles. Rite now i have joe gibbs break-in oil which is high in zinc. After the 500 mile mark and then going to use valvoline vr1 race oil.

You can see that your oil is clean but what about your oil filter? I would pay the extra doe to change my oil three times in the first 1000 if I was breaking in my motor.

 

[2GFWDbeast]

if my motor ####s up in the first 500 miles im bring it back to the shop that built it for me and they can rebuild me a motor on there own cost. They told me to wait 500 miles to change out the oil, and then use the valvoline zr1 race oil

 

[Tyeler18]

if my motor ####s up in the first 500 miles im bring it back to the shop that built it for me and they can rebuild me a motor on there own cost. They told me to wait 500 miles to change out the oil, and then use the valvoline zr1 race oil

Good luck with that one. Hopefully you've got a trustworthy shop because the last "trustworthy" shop I ever took my car to ####ed me out of over $3000 and 8 months of time.

They'll find some excuse saying your broke it in wrong.

 

[2GFWDbeast]

ill just bring them to court and drain time and money out of there day, and if they wanna screw me over out of 5000 grand then i will give them the worst reputation ever. If they wanna play hardball with me im game all day long .

 

[Tyeler18]

ill just bring them to court and drain time and money out of there day, and if they wanna screw me over out of 5000 grand then i will give them the worst reputation ever. If they wanna play hardball with me im game all day long .

Until you run out of money to pay for your lawyer and court fees. Trust me, been there, done that.

 

[Indian]

Your asking questions, and you aren't listening. Most of these guys have been around the block more than once, I would listen to what they have to say vs your "shop."

 

[2GFWDbeast]

Your asking questions, and you aren't listening. Most of these guys have been around the block more than once, I would listen to what they have to say vs your "shop."

My shop no its a local machine shop thats been in the game for 60 years who builds n/a race motors and also has there own 6 sec drag car. Listen to what people have to say OK since there telling me i should change it at 20-100-200 and so on to many different answers and im already past all those miles so its a little to late now. Other people say use diesel oil, and other are saying wtf to it. Im sure everyone including shops have there own ways and opinions on methods and what not. I wanted a big variety of answers which im getting.

 

[gst96spyderman]

Diesel oil is used because of the high zinc levels and other detergants that filter out all the crap already formed. This is used to perserve the life of the internals. But if the internals are cleaned or new, what is the point? Just a waste of money.

 

[RadDsm]

I changed the oil at 50, 100, and 200 so far. I'll be doing another at 500 and 1000, then in regular 2500 mile increments.

Even if it's excessive, nothing beats being sure that you are flushing out any foreign material. I definitely don't want to risk a freshly built motor on anything.

 

[ramsack]

Has no one else noticed how his engine is 160, 128, 130, 160? Doesn't it seem odd that the middle two cylinders are low but basically the same compression? Sounds like a possible leaky head gasket to me.

 

[2GFWDbeast]

Has no one else noticed how his engine is 160, 128, 130, 160? Doesn't it seem odd that the middle two cylinders are low but basically the same compression? Sounds like a possible leaky head gasket to me.

You didnt read very well. Cause i posted new numbers. Its a 168 150 150 168 now.

 

[ramsack]

No I didn't. I did skim through every post in 3 pages. I just must have missed it by thinking it was the old numbers.

 

[dsm-onster]

No stop and think. He did read well. just not enough. But an initial difference that high is an instant alarm. and won't go away. The difference between the outer two and the inner two is still a significantly different magnitude as it was initially. . . The Factory Service Manual published by Mitsubishi Corporation states that if there is a difference of more than 14psi across the cylinders then it is beyond service limits and you have an issue. In fact, this is for an old 150K or more motor, not a fresh build. What is the difference between your center two and your outer two right now? How old is your build?

In my experience, if the motor isn't broke in properly, typically ALL the cylinders read low. What is going on here? . . . Further, a shop that says everything is fine as long as the compression is within 15-20% of each other across the board is NOT a quality shop. 15psi; NOT 15%. They can have as many 6 second 1500lb nitro/meth 7.5 litre funny cars as they want. They can be in business for 120 years. But in reality, the vast majority of those years of experience is pushing blocks with different nickle content/different ring mettalurgy/different load curves/different block and ring and piston structure. Taking it easy on a 6 second car is putting it into the 8s. But are the rings/bearings/cylinderwalls/journals run hard? And in continuation of reality, their answer is still wrong about break in procedure; and now their answer is DEFINATELY very wrong about compression number spread. So what is your real world experience with their advice? Your center two cylinders are out of factory spread service limits.

I hope you can catch the problem and bring the numbers more into line with each other, by just running the he!! out of it like you were supposed to in the beginning. But a difference like that means there could very well be another problem.

FYI, stock 7.8 compression is 165psi per the back of the Mitsubishi Corporation printed FSM in the quick reference chart and elsewhere in the manual (it's not a typo). . . With stock cams. Which alters compression results a little, in my emperical experience. The 168psi is OK for an 8.5 motor with healthy cams. So you have an issue with the center two cylinders. You really should remain "pissssed!!!!!" instead of defending your $5000 expenditure . . . Again I hope the numbers continue to come more in line, by not listening to the rebuilder. I am sorry you've had a bad experience. For a factory to crank out 100s of thousands of blocks by a robot that make the same compression and even across the board, it makes me just shake my head at the typical machine shop trend to sweep under the table their shoddy workmanship. Reasoning skills, the one advantage humas have over a machine, should be applied to quality instead of defusing there poor results.

 

[LiquidX]

Just to make sure, you are testing each cylinder the SAME way by cranking the same number of times on each?

I'm with Matt on this, you do have an issue somewhere as you shouldn't see a significant difference between cylinders as you are telling us.

 

[thomcasey]

baby first 500 miles,1/2 of max boost till 1000 miles,full boost till 1500 miles should have good compression. with regular oil changes. I recommend diesel oil for brake in

He is in Wisconsin, diesel oil would be a bad idea. Plain ol' dyno juice is just fine for the multiple break in changes. Plus, being a turbo, just like every one says. do NOT baby it. Drive it like it was meant to be driven.

 

[2GFWDbeast]

starting from right cylinder 4-3-2-1

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cylinder 4

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cylinder 3

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cylinder 2
http://i1218.photobucket.com/albums/dd412/Karl_Krienke/005.jpg?t=1297899338

 

[dsm-onster]

3 and 2 are shiny like they have been steam cleaned from a coolant leak into them. . . headgasket?

 

[2GFWDbeast]

how can i determine that it is the head gasket. Leakdown test??

 

[LiquidX]

That would be your best course of action right now as the leak down test will allow you to see/hear where the lower compression is leaking out to.

 

[2GFWDbeast]

do you know if you can rent the leak down application from like autozone or something. I know you need a air compressor.

 

[LiquidX]

I believe you can. IIRC I think some compression testers are also capable of being converted into a leak down tester as well. All you really need is just a gauge, fitting to screw into the spark plug threads and a compressor fitting.

 

[RadDsm]

Did you ever retorque your headstuds after the first 100 miles?

 

[2GFWDbeast]

Did you ever retorque your headstuds after the first 100 miles?

EHHHHHHH no. I thought that you torque them then drive it till it hits operating temp, let it cool down then re-torque them again.

 

[allrice4g63]

yes its a good idea after 100 and im assuming you are running arps?