Okay so a few of you might know I've been building a 355 LT1 boost motor to pair up with one of RealQuick's turbo kits. I've been working my butt off putting this thing together and finally, it's drivable. Since I have not sent my fuel sending unit out to Lonnie yet for his dual in tank set up, I'm still on the stock pump...so I put a 3psi spring in it and I've really kept my foot out of the throttle because I'm scared of the stock pump. I haven't seen more than 55kPa from the MAP sensor on my datamaster logs. Basically I'm just trying to get some cruising in and make sure I have the bugs worked out before I start running it hard. I already found that my upper radiator hose is ballooning up so I ordered new hoses, and apparently I have an oil problem. I'm not sure if my T70 is leaking oil through the seals (possibly my oil return line is not far enough lower than the turbo), or I damaged my valve seals when I installed them. It smokes pretty bad on start up and if I rev it up at all when its sitting idle. I didn't notice the smoke at all when I drove it down the road though. What do you guys think it is?

 

Mike, glad to hear its up and running. Are you running an oil restrictor on the feed line? Alot of guys run them because the turbo sees alot of oil and if doesnt drain fast enough it will seep past the seals and smoke.

 

Whats your heads/cam setup and what kind of #'s are you looking for?

 

If you just built the motor, are your rings seated yet?

I was just thinking, if your keeping your foot out of it, maybe those rings haven't seated...

 

Yes, the -3AN flange I installed on the feed side of the turbo has a built in restrictor of 1.6mm in diameter so I don't think thats the problem but I suppose it could be.

Stock head castings, gasket matched by myself and I opened up the chambers to about 56-57cc. 3 angle valve job and 2.02/1.60 stainless valves. If these heads don't seem like they're working out, I'll go with some trickflow's or even just a set of LT4's down the road.
The cam is Jim's old turbo cam (INTMD8)
The cam specs are-

Intake 3014 lobe 218 @.050 .571 lift with 1.6 rocker

Exhaust 3034 lobe 218 @.050 .556 lift with 1.6 rocker

113 LSA 111 ICL

IVO 2 atdc
IVC 40 abdc
EVO 44 bbdc
EVC 6 btdc
For Jim, the cam stopped making power around 6000rpm so that will hopefully makes things easy on my rods and bearings.

I'm looking to reach 600rwhp if the turbo will get me there...seems easily doable if it were an 6-speed car but through the stalled auto I don't know. If it makes that power at 12psi, I'll go for more. If it makes that power at 18psi, NO WAY am I going more and I'm probably lucky I did not blow up a piston!

Well, that was the other thing I considered but the way my luck as been putting this car together, I'm guessing it couldn't be as easy as that.
So to seat the rings are you suggesting I need to be a little harder on it? How hard?

If so, (and this is for anybody to answer) do you think the stock fuel pump on 60# injectors can handle 3-4psi? Once I get my fuel pressure, boost, EGT and wideband hooked up, I'll feel more comfortable getting into the throttle.

 

You have an .063 restrictor in there now, so I think that is fine.

I wouldnt lean on anything without the WB hooked.

 

unhook your charge pipes and beat on it na a bit if you are worried about the rings seating.

 

How many miles do you have on this new shortblock?

Break-in techniques/theories seem to be similar to the "water/meth mix vs pure water vs pure meth" or "supercharger vs turbo" or "my dad can beat up your dad" arguments on this board. Everyone and their grandma has a different idea on what you should/should not do. If you didn't assemble the bottom-end yourself, I would recommend consulting your engine builder on what they think you should do.

I've always paid attention to what the more knowledgeable guys on this board have to say. So far, it's worked out for me.

I broke in my newest shortblock a month or two ago. Prior to the rings seating anytime you blipped the throttle (free-revving or under load) light blue smoke would exit the tailpipe; under heavier throttle lots of somke. I took the aggressive route to ring-seating, and got everything seated on a back road. No blue smoke ever since, and clean clean oil.

Just my $.02. Take it with a grain of salt, I am not familiar with your setup...nor am I in any way an "expert" in this area.

Good luck!

 

Only about 30 miles on it thus far. I built it myself and since posting I took it out and ran it a little harder. Never went above 66% throttle. Actually, my runs where I hit boost were at about 45% throttle and it seemed to run pretty good except I discovered a vibrating problem above 4500 RPM. I'm thinking I damaged the crank hub and I have a thread addressing this at LT1 Engine Tech forum on this site. In addition, I uncovered some pretty bad oil leaks which I fixed today. I pulled the driver's side plugs and the #1 and #7 each are saturated with oil....I'm guessing thats where my leaky valve seals are at??? The 3 and 5 plugs didn't look too terrible. AFR was down around 12.0:1 when I hit boost above 4500RPM...I only revved to 5600. However, it was closer to 14.0:1 at the ligher throttle boost conditions. Granted I still have just a 3psi spring in the gate and was letting off within about a second of seeing the MAP read 103 KPa on Datamaster since my boost gauge is not working yet--so when I say boost, I bet it was about 1psi, if that. I changed the oil for the first time today. I didn't like it because I could see the metallic glistening of a freshly built motor...I'm assuming that's normal but I hope to see that disappear after the next oil change!