Hey guys, decided to put a hemi in my demon. It's going to be a summertime daily driver. I have a relative that works in a junkyard and can get me a stuff for a killer price. I'm planning on running fuel injection. My question is, what all should I have him pull for me? I'm assuming just engine, tranny, (545) computer, and harness. anything I might be missing? When using a stock wiring harness and computer is there any nuances I should know about beforehand? Money is not too big of a problem as I set a budget of 27,000 for doing the entire car, but money saved someplace is money I can spend on something else!! Also, has anybody incorporated late model gauges to go with the late model hemi???
parts to gather
- Thread starter D-rock
- Start date
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DadGum_Teen
Well-Known Member
Your definitely gonna need different motor mounts, the older pokes here could probably tell you if you can steal them from another car, but for a garunteed fit try schumacher.
And if the wiring harness is pulled off a sitting car, make absolutely sure the terminals don't have corrosion. A little bit can cause a good amount of problems
And if the wiring harness is pulled off a sitting car, make absolutely sure the terminals don't have corrosion. A little bit can cause a good amount of problems
the alterktion front suspension can be ordered with the correct mounts for the hemi engine. I'll also make sure he gets a good harness for me. Are the factory harnesses a b*&%$ to modify? I'm mecp certified, so I'm fairly competent with wiring, but there is still a ton thats over my head.
boden
Well-Known Member
Hotwire auto has a good list of things you may want to consider getting here.
http://www.hotwireauto.com/?page=support
You definately will want either an accelerator pedal or a pedal position sensor. I ended up modifying a truck pedal. Many people like the 03 truck pedal position box that uses a cable. Different vehicles have different sized pedals with a variety of mounting configurations.
Temperature sensors.
Emission components are something you may want to get. As far as I can tell you have to get a custom tune to disable the rear O2 sensors, which I plan to do. I am getting rid of the old charcoal canister and using the new NVLD pump and canister. I just have to figure out where to mount it.
If you are going to use a manual fan, you will want a fan clutch. I'm using one for a durango. The truck one is too long. Many people prefer electric fans though.
If you want to use late model gauges you have to make sure the computer and gagues come from the same vehicle so the VIN matches. If it doesn't the engine won't start. I have a gauge cluster that I wired up to plug into my diagnostic port, just to check things as I was doing some testing and it only works if I plug it in after the engine is already running. I am planning to wire in an overhead console. I'm not sure if the mileage part will work, but if nothing else I will like the temp and compass readings.
A factory service manual and lots of patience was the key to my success in getting mine wired up to run.
http://www.hotwireauto.com/?page=support
You definately will want either an accelerator pedal or a pedal position sensor. I ended up modifying a truck pedal. Many people like the 03 truck pedal position box that uses a cable. Different vehicles have different sized pedals with a variety of mounting configurations.
Temperature sensors.
Emission components are something you may want to get. As far as I can tell you have to get a custom tune to disable the rear O2 sensors, which I plan to do. I am getting rid of the old charcoal canister and using the new NVLD pump and canister. I just have to figure out where to mount it.
If you are going to use a manual fan, you will want a fan clutch. I'm using one for a durango. The truck one is too long. Many people prefer electric fans though.
If you want to use late model gauges you have to make sure the computer and gagues come from the same vehicle so the VIN matches. If it doesn't the engine won't start. I have a gauge cluster that I wired up to plug into my diagnostic port, just to check things as I was doing some testing and it only works if I plug it in after the engine is already running. I am planning to wire in an overhead console. I'm not sure if the mileage part will work, but if nothing else I will like the temp and compass readings.
A factory service manual and lots of patience was the key to my success in getting mine wired up to run.
Try and get an 05 or later motor & trans as they share the computer. I have seen a number of guy's struggle trying to get the factory harness to work, some have done it, most have not. Your best bet would be to buy one from Hotwire ($1050) and have them re-flash your pcm. You will need an electric fuel pump, preferably one in the tank (Rock Valley), the external pumps tend to burn up. (2) O2 sensors, DBW gas pedal. The AlterK is a nice unit, and will make life a lot easier. Good Luck...
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