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Stupid questions about running without boost

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spyderdrifter

10+ Year Contributor
5,267
711
Jul 11, 2009
Somewhere in, Colorado
Here's the situation: I've rebuilt my car, OEM grade everything. I got my turbo out being rebuilt right now and I probably won't get it back until late next week or the early the following week. I have a POS 16g that developed shaft play when I fired the engine up the first time, but not going into that here.

I'm moving to another part of town this weekend. Would it be safe to throw on the 16g and rig the wastegate open so I build no boost so I can drive the car over the 10 mile trip? I'd be doing this late at night/early morning where there's next to no traffic in my way and would only be doing 40mph at most. If this is doable without hurting my engine, there would be no oil going to the turbo since it won't need it, or coolant. Those lines will be either blocked or looped to prevent leaks. I know the engine runs well, as I had driven it for a few minutes when I learned that turbo didn't work.

I don't want answers regarding how retarded this is. Trust me, I already think it's f@%king stupid, but I need to get my car moved and if I can do it myself without blowing the engine, then I'm ok with being a little stupid. :| :toobad:
 
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you will run rich as hell but its no different then driving with a boost hose popped off just my 2 pennies.
this might be out of the question but you could throw 1g nt manifold on it
 
just go really easy on the gas slow take off easy I also would not limit my self to 40 mph i would probably see where the car wants to run if it like 25 then do it but it might take higher better but I think you should be fine i have limped home with a blown boost hose before it sucked but it did it . .... anytime
 
I would also block off the turbo's oil feed and drain with a bunch of thick petroleum grease or product similar, not to save the turbo but to rather take precautionary measure on your induction system. You don't want your turbo journal bearing seizing up because of no lubrication and heat. It may stop your system from receiving any air. Personally I'd take the time to connect the oil but it depends on your risk.

I've ran another 2g without a turbo before that I had to move 6 miles, except I borrowed a pipe long enough to connect the maf directly to the tb elbow and to connect the maf to the harness. I blocked-off the oil feed and left the stock oil drain pipe on to prevent spills, connected the coolant in and out together. Needless to say it still ran like crap (because non of the o2 sensors read anything) but worked .
 
I would also block off the turbo's oil feed and drain with a bunch of thick petroleum grease or product similar, not to save the turbo but to rather take precautionary measure on your induction system. You don't want your turbo journal bearing seizing up because of no lubrication and heat. It may stop your system from receiving any air.

How would this prevent air from flowing into the system? The bearing seizing up is honestly not a concern because the turbo is trashed anyway (was a knock-off). I'm not against hooking the oil up to turbo to prevent this, but to me it seems a little pointless. Not by any means a bad idea though, I'm accepting all advice. Also, if I blocked the oil drain line with grease, wouldn't the oil become contaminated? Or is that why you said petroleum grease? :hmm:

As of now, I plan to cap the oil feed port on the OFH since I still have the threaded port cap. Was also going to place a block off plate between the turbo's center section and the drain pipe, and have that all bolted together.
 
Do not block off the oil, just leave it alone and unhook the WG arm. The turbo is still going to spin so the oil will keep the shaft lubricated so it wont seize. Just like any other off boost conditions.. The same thing goes for the fuel trims. You would not run rich either.

Dont overcomplicate things here.
 
How would this prevent air from flowing into the system? The bearing seizing up is honestly not a concern because the turbo is trashed anyway (was a knock-off). I'm not against hooking the oil up to turbo to prevent this, but to me it seems a little pointless. Not by any means a bad idea though, I'm accepting all advice. Also, if I blocked the oil drain line with grease, wouldn't the oil become contaminated? Or is that why you said petroleum grease? :hmm:

As of now, I plan to cap the oil feed port on the OFH since I still have the threaded port cap. Was also going to place a block off plate between the turbo's center section and the drain pipe, and have that all bolted together.

It was ment to say, that if you were going to block off the the oil feed from the OFH and oil drain from the pan, to also block them off from the turbo but jam the turbo with a bunch of grease or lubricant(Meaning no circulation through to the oil pan). That way the turbo doesn't get damaged to the point where little metal chunks get sucked into your intake manifold or so it wont prevent the compressor wheel from rotating. Of course its not about saving the turbo, but protecting the engine.
 
You have two options.
1) fully install the blown 16g, unhook the WGA and use wire to hold the flapper open
2) remove the turbo, loop the oil and coolant lines, install a 1G non-turbo exhaust manifold and intermediate pipe and find a way to connect the MAS directly to the intake manifold

you will run rich as hell but its no different then driving with a boost hose popped off just my 2 pennies.
this might be out of the question but you could throw 1g nt manifold on it
No he won't run rich at all.

just go really easy on the gas slow take off easy I also would not limit my self to 40 mph i would probably see where the car wants to run if it like 25 then do it but it might take higher better but I think you should be fine i have limped home with a blown boost hose before it sucked but it did it . .... anytime
A leak between the MAS and intake manifold like you had will cause the loss of metered airflow. That's why you ran rich. If he does it right, then that won't be an issue for him.

I would also block off the turbo's oil feed and drain with a bunch of thick petroleum grease or product similar, not to save the turbo but to rather take precautionary measure on your induction system. You don't want your turbo journal bearing seizing up because of no lubrication and heat. It may stop your system from receiving any air. Personally I'd take the time to connect the oil but it depends on your risk.
I don't understand this. If you just leave the lines connected to the turbo and have the wastegate open it's very unlikely to seize.

In what way would it prevent the engine from getting air?

I've ran another 2g without a turbo before that I had to move 6 miles, except I borrowed a pipe long enough to connect the maf directly to the tb elbow and to connect the maf to the harness. I blocked-off the oil feed and left the stock oil drain pipe on to prevent spills, connected the coolant in and out together. Needless to say it still ran like crap (because non of the o2 sensors read anything) but worked .
Why didn't the sensors read anything?
 
Thanks for the info guys. I think I'll run by the salvage yard and grab a 1g N/T exhaust and intake pipe to limit hassle like Delta mentioned. If I can't get those, I'll hook everything up like normal and wire open the WG and hook up the oil and reroute the coolant to bypass the turbo.


Is this a freshly built engine? If so this will hurt the break-in.

No, not really a fresh rebuild. I rebuilt the head basically because I had to replace the valve seals. The short block wasn't rebuilt except for replacing some seals and gaskets.
 
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