Engine Break-in

Marc87GN

New Member
I did a search, but I couldn't find anything related to this specifically. I have been driving it easy not seeing more than about 2-3 psi for the first 500 miles. Last night, with just over 500 miles, I pushed it to 10 psi for the first time at 1/2 throttle and the car pulled to 100 mph real well. There is no smoke coming out of the tailpipes and the O2s were in the low 800s. I have changed the oil about 5 times (7-8 qts at a time thanks to RJC :) ) and the Turbolink logs look good. When would be a good/safe time to start putting 18 psi+ through it?

The only issue I have noticed is the BLMs at idle are in the low 140s, but I would expect that since the chip was burned for a stock set up. Since then, I added P&P heads/intake, 62 mm throttle body, PT61, FMIC and the block came with a more aggressive cam. I would think there is much more air entering the engine at idle and the computer is trying to correct. Anyway, I'm itching to see 18 psi(HD WG 18-30 psi) at full throttle because even 10 feels good at part throttle. I have no problem waiting until 1K if most people believe that 500 miles isn't enough.

Thanks!
 
You'll get many different opinions on this one so here's mine...I do exactly as you did on new engines...take it easy for 500 miles changing oil often and cutting open filter to check for any metal...after that it's ready to go...I took mine to the track around 600 miles...took it easy though as I didn't have it dialed in...I would say go ahead and hit 18 PSI...
 
well im not an expert, but in 500 miles the rings have probably seated almost 100% and the cam is broken in. I would be willing to turn the boost up, but i would be worried about the chip not supplying enough fuel for your current setup. But again, i have about 800 miles on my dads 86 GN that im driving this week and it has seen quite a few 15-16 psi passes so far, and will probably see the track with in a week. I've always believed in a hard break-in ;)
 
Thanks for the opinions guys. Now that I think about it, I never cut open the filters, but I do have them so I will tonight. I just caught all of the oil out of a filter into a clear cup and looked at it. I have the Extender chip so the BLM problem is only at idle it seems. Once the rpms went above about 1200, BLMs immediately went to 128 so I don't think it's a problem.
 
It's always a good idea to cut the first few filters open...just make sure you use tin snips or some other cutting tool that won't put metal from the filter housing into the filter...
 
MSDGN said:
It's always a good idea to cut the first few filters open...just make sure you use tin snips or some other cutting tool that won't put metal from the filter housing into the filter...

Good point. I have them lined up, but can't remember which was first so I will cut them all open.
 
Sorry I do not have a cite, but I have read, from a famous engine builder that most gear heads would recognize, that rings that do not seat within minutes of starting will never seat.

Also said that the only break-in is for the flat tappet cam and lifters that is complete within 30 minutes.

While I have always taken it easy for the first, about 500 miles, changing the oil after the very first warm up/cam break in, then again about 500 miles later, the experts say there is not much of a break-in required. If there was a long break-in then why would the engine builders put fresh engines directly on a dyno?
 
Blown&Injected said:
Sorry I do not have a cite, but I have read, from a famous engine builder that most gear heads would recognize, that rings that do not seat within minutes of starting will never seat.

Also said that the only break-in is for the flat tappet cam and lifters that is complete within 30 minutes.

While I have always taken it easy for the first, about 500 miles, changing the oil after the very first warm up/cam break in, then again about 500 miles later, the experts say there is not much of a break-in required. If there was a long break-in then why would the engine builders put fresh engines directly on a dyno?

You make valid points. The only thing is, I would change the oil more frequent than that. The reason is fuel gets in the oil and will wash the walls/bearings down. On my second oil change with only 150 miles on the engine, I could smell gas in the oil. After that, I changed it every 90-100 and I didn't smell any the last time.

I took it up to 18 psi last night and had about 1.1 KR I believe on the shift, but the car felt violently fast busting the tires loose at 40 mph. I think I need to close the gap from .032 to .028 because I would swear I heard a miss at 5300 rpms, but showed zero KR. I definitely like the way it pulls in every gear with this setup and I hope it does well at the track.
 
Marc87GN said:
You make valid points. The only thing is, I would change the oil more frequent than that. The reason is fuel gets in the oil and will wash the walls/bearings down. On my second oil change with only 150 miles on the engine, I could smell gas in the oil. After that, I changed it every 90-100 and I didn't smell any the last time.
How does fuel contaminate the oil? Weak ignition module/coil? Miss-wired coil to module? Leaking injector?
 
TurboGN said:
How does fuel contaminate the oil? Weak ignition module/coil? Miss-wired coil to module? Leaking injector?

Rings not seated fully and running rich. I was trying to correct the high BLM at idle and it also raised the O2s at part throttle and I saw O2s in the 870s-890s at part throttle. I corrected it and now see low 800s, but I remember definitely smelling fuel in the oil on the 2nd change. Oh well, I will be back to tuning tonight.
 
Sorry to be off-topic, but if your fuel vapor canistor is laying on its side, would that cause the fuel smell? (i'm running rich as well, but not leaking fuel)
 
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