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Discussion Starter #1
Hi all,

I am fininshing up my Wagon swap and Im noticing that I dont have much power availible. Its enough to run around town and get on the highway and things but you wont be peeling tread from the tires with it.

When I put the exhuast on It seems like I lost even more power and I cant hear the turbo spool up. Im sure it is but It feels like it is taking MUCH longer when compared to just a downpipe. That makes sense from a backpressure point of view. Could exhaust make that much difference on a stock engine? Will I ever hear my turbo again??

Next, If exhaust can be so important, what kind of changes can I make to increase hp without getting into the guts or impacting reliability, milage, and life? What gains Could I expect from an aftermarket Intercooler and maybe a gov spring? Will that impact life of the engine? Is 160-180hp achievable with minor mods?

Last, Most of the time when accelerating, the pedal is on the floor. But my coolant temp is always around cool around 180-190, Can this hurt the engine? Ive read threads on burning pistons etc and want to make sure Im not in danger of burning this thing up before I get to drive it much.

Thanks!
 

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I feel you must monitor the boost and EGT. Water temp can reach 205-210 with no problem but the fan better be working and you must have 50-50 antifreeze. EGT will tell you when you'r going to melt a piston. If you do not have these gauges, a rule of thumb is, if at WOT if the engine is not gaining RPM back off. FYi when i spank my 6BT(and thats all the time) i run 205temp in the coolant, 170-190 oil temp, 12lbs boost, and an EGT at about 1000Deg on a hard spank. Thats pulling 7500# up a 4%grade holding 65mph. AS for exhaust piping, i removed the muffler and run straight out the stock pipes to the back. The turbo reduces most noise. I pulled all the Air cleaner assembly and run a K-N on the turbo inlet. I have the first step up injectors(they say 30-40 hp increase with stock pressures) the fuel rod in the pump i believe is a bullydog and when ever i can i burn drain oil i cleaned up. And my 400,000 mile Dodge still has 30lbs oil at idle and 70 at 65mph. Now, as for more power. You gotta know where you are to see where you are going. Gauges being the most important. For mods. Low restriction exhaust is a must, same for intake. Bigger jectors make power but lower mileage and longetivity. Pump mods done correctely are 50% of the struggle. Turbo mods are expensive but again, done correctely make big power but and again cut into you're engines life.(I like to do one mod, monitor, take notes)If you are looking for infrequent power look at water-alky-nos injection. Oh and don't scrimp on the gauges, the cheap arse tiny ones stink. I know they cost a fortune but good big gauges are the only way to go. Theres my 2 cents, good luck and i hope i helped you.
 

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Isuzu reliability tester
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Ive seen plenty of slightly bigger injectors help mileage actually just depends on several factors.

Can you tell us about your exhaust? What turbo? What kind of muffler? (hope its not a heavily chambered muffler) 180-190 coolant is normal or fine.

Turbos can be very cheap like around $250 for a nice he341 or similar turbo.

If anything remove the muffler and see if that helps at all. crank the fuel screw (research more powe from the VE cummins) and start from there with your trouble shooting.
 

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Discussion Starter #4
Ok, Looking through my reciepts I found that I did buy the 101 muffler from hearthrob. The most restrictive one they have! Turbo and injectors are stock and the pump is untouched. Im really looking for cleaning up the flow both in and out first then Ill go from there. Is there any damage that can occur from too much backpressure?
 

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Isuzu reliability tester
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Yes damage can occur due to back pressure but you have to be running some big power for that, at your level I wouldnt worry about it. I would think about removeing the muffler to see how much that helps and if it does get a new muffler. I am going to run a dynomax ultraflow muffler 3" on my 01 jeep, it should help muffle things pretty good but still be flow through so no real restriction.

To make a nice cheap unrestricted setup good to 250+ hp at the wheels look for an he341, some 3" exhaust with a flow through type muffler and a very large quality air filter like a donaldson.
 

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Back pressure will drop the power level down more than you think,it will also raise the egt's.

Take off the muffler and see how different it is and then you can.

1. install a gov spring .
2. No muffler or get one made for a diesel , you can also cut down a diesel muffler to fit where you need it if it's to long.


Scott
 
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