Hemi Swapping a perfectly good 70 Duster

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With the exception of the catch can and some AC lines (which won't be visible), the engine compartment is pretty much done. I painted the HEMI badging on the coil covers with the same paint that's on the exterior of the car. I was having trouble deciding which color to go with, but a good friend who has a really good eye for design suggested gloss black. Considering he's a graphic designer and he hasn't steered me wrong on other things, I had to listen. He was right again. I'm super happy with the appearance. I've said it many times that I was trying hard to knock the ugly off this thing and I think I accomplished that. Dare I say it looks better than the LA engine???


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I LOVE it!!!! Well done!! :thumbsup:
 
With the exception of the catch can and some AC lines (which won't be visible), the engine compartment is pretty much done. I painted the HEMI badging on the coil covers with the same paint that's on the exterior of the car. I was having trouble deciding which color to go with, but a good friend who has a really good eye for design suggested gloss black. Considering he's a graphic designer and he hasn't steered me wrong on other things, I had to listen. He was right again. I'm super happy with the appearance. I've said it many times that I was trying hard to knock the ugly off this thing and I think I accomplished that. Dare I say it looks better than the LA engine???


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Looks very nice!!!!
 
Got the exhaust installed and messed with the cranking and idle fueling. It seems pretty decent, but will definitely need more tweaking. It’s so hot this time of year the water temperature never gets below 75 degrees even after sitting a day.
I decided to try the auto tune function in tuner studio. I never used it before but figured it was worth a try. So I set off for my first drive. I hadn’t even gotten off my street and I could see the auto tune doing its thing. It was starting to get super lean and within a second it brought it to the value on my AFR table. I was pretty impressed. I did some easy driving at varying RPM to let the ECU do its thing, gradually giving it more throttle. I put about 10-15 miles one it and made it back home with no issue. I haven’t floored it yet, mostly because once I put the carpet back in (added some insulation) I’m not getting 100% throttle.
Here’s some initial thoughts:
Exhaust note is much different. I feel like it’s a higher pitch and less “grunty”. Still sounds awesome.
The engine runs much smoother. The 408 sounded and felt like it was wanting to be shifted at 3500 when just normal driving. This thing is just as smooth and happy at 4500 as it is at idle.
Throttle spring is much stiffer on that 90mm. Going to have to train my foot on the input required.
Seems like noticeably less torque off idle. I may not be able to start autocross in 2nd like I did with the 408. This may also be related to my foot being a slow learner and using muscle memory.
It pulls pretty damn good, but not quite up to the 408 yet. Note I haven’t done any timing tuning (very conservative) and it was almost 100 degrees when I was out. Also-not 100% throttle. The 408 did seem to be down on power when it’s this hot out.
I did about 6 long pulls in a row a temp got to 200. It dropped to 190 when I stopped hammering on it.
Overall I’m super pleased and it’s definitely a great start to what I think will be an excellent platform for this car. Planning on putting some miles on it this week to keep dialing in the fuel. Also need to fix that throttle!!!
 
Got the exhaust installed and messed with the cranking and idle fueling. It seems pretty decent, but will definitely need more tweaking. It’s so hot this time of year the water temperature never gets below 75 degrees even after sitting a day.
I decided to try the auto tune function in tuner studio. I never used it before but figured it was worth a try. So I set off for my first drive. I hadn’t even gotten off my street and I could see the auto tune doing its thing. It was starting to get super lean and within a second it brought it to the value on my AFR table. I was pretty impressed. I did some easy driving at varying RPM to let the ECU do its thing, gradually giving it more throttle. I put about 10-15 miles one it and made it back home with no issue. I haven’t floored it yet, mostly because once I put the carpet back in (added some insulation) I’m not getting 100% throttle.
Here’s some initial thoughts:
Exhaust note is much different. I feel like it’s a higher pitch and less “grunty”. Still sounds awesome.
The engine runs much smoother. The 408 sounded and felt like it was wanting to be shifted at 3500 when just normal driving. This thing is just as smooth and happy at 4500 as it is at idle.
Throttle spring is much stiffer on that 90mm. Going to have to train my foot on the input required.
Seems like noticeably less torque off idle. I may not be able to start autocross in 2nd like I did with the 408. This may also be related to my foot being a slow learner and using muscle memory.
It pulls pretty damn good, but not quite up to the 408 yet. Note I haven’t done any timing tuning (very conservative) and it was almost 100 degrees when I was out. Also-not 100% throttle. The 408 did seem to be down on power when it’s this hot out.
I did about 6 long pulls in a row a temp got to 200. It dropped to 190 when I stopped hammering on it.
Overall I’m super pleased and it’s definitely a great start to what I think will be an excellent platform for this car. Planning on putting some miles on it this week to keep dialing in the fuel. Also need to fix that throttle!!!
I bet you had a big smile on your face after driving it and have little to no issues. I know I would. :thumbsup:
 
That's awesome.. Running and driving with plenty of time left to enjoy it, before it's cold again. The Hemi is definitely happy at just about any RPM. I've found that the Dart feels pretty normal, just as a daily, but when you put a foot deep in it's ***.. It's a completely different machine. I think once you get everything dialed in and wot, you should be very pleased. BIG GRIN! I can't remember what cam you went with but that may be why it feels a little less torqish off idle.. but I'm sure it makes that power elsewhere.
 
That's awesome.. Running and driving with plenty of time left to enjoy it, before it's cold again. The Hemi is definitely happy at just about any RPM. I've found that the Dart feels pretty normal, just as a daily, but when you put a foot deep in it's ***.. It's a completely different machine. I think once you get everything dialed in and wot, you should be very pleased. BIG GRIN! I can't remember what cam you went with but that may be why it feels a little less torqish off idle.. but I'm sure it makes that power elsewhere.
I had to force myself to come home with it after I realized I was out for a while and should likely go home and check stuff over. No oil or coolant drips! I may be more happy about no oil drips than the new exhaust note! Hahaha.

The good news is, the winter rarely shuts me down from driving, unless its a wet winter.

I've got the Cam Motion Titan 2 cam, which is 225/235 @ .050 and .594/.577 lift. They don't have a published PRM range, but they do recommend a 28-3500 converter (I don't that crap) and state "improved power in the midrange and upper RPM with emphasis on midrange power and torque." This is the reason I chose this cam. I felt like it would be good on the autocross. I can definitely feel it "turn on" the torque. I have a feeling I'll be bumping the rev limiter until I can train my ears again. It's so smooth I feel like I'm at a lower RPM and look down and I'm at 5500.


Side note I forgot to mention, my homemade one wire alternator modification works beautifully! $50 1 wire alternator, yes please!

Also a follow up to me being concerned about the oil pressure, Once the oil is warm, pressure is around 50 at idle. When cruising its around 70. I'm good with that!
 
I had to force myself to come home with it after I realized I was out for a while and should likely go home and check stuff over. No oil or coolant drips! I may be more happy about no oil drips than the new exhaust note! Hahaha.

The good news is, the winter rarely shuts me down from driving, unless its a wet winter.

I've got the Cam Motion Titan 2 cam, which is 225/235 @ .050 and .594/.577 lift. They don't have a published PRM range, but they do recommend a 28-3500 converter (I don't that crap) and state "improved power in the midrange and upper RPM with emphasis on midrange power and torque." This is the reason I chose this cam. I felt like it would be good on the autocross. I can definitely feel it "turn on" the torque. I have a feeling I'll be bumping the rev limiter until I can train my ears again. It's so smooth I feel like I'm at a lower RPM and look down and I'm at 5500.


Side note I forgot to mention, my homemade one wire alternator modification works beautifully! $50 1 wire alternator, yes please!

Also a follow up to me being concerned about the oil pressure, Once the oil is warm, pressure is around 50 at idle. When cruising its around 70. I'm good with that!
Agree on the RPM feel and sound.. I'm at 3k doing 70 and it doesn't bother me. Drove me batty with the LA. I'll probably do some trans upgrades this winter and honestly, I'm not even sure I'll go with an OD. I just don't care for this lockup 904 (that doesn't lock), so a 727 and a stahl would be a great improvement. Might go through the engine too.. pop some caps, check things over, cam and a tune. Need to add front disc as well. Already have next years Power Tour on the brain. Hindsight stuff and anything to avoid a paint project... Have I mentioned how much I hate paint and body. It's the Devil!!
 
Agree on the RPM feel and sound.. I'm at 3k doing 70 and it doesn't bother me. Drove me batty with the LA. I'll probably do some trans upgrades this winter and honestly, I'm not even sure I'll go with an OD. I just don't care for this lockup 904 (that doesn't lock), so a 727 and a stahl would be a great improvement. Might go through the engine too.. pop some caps, check things over, cam and a tune. Need to add front disc as well. Already have next years Power Tour on the brain. Hindsight stuff and anything to avoid a paint project... Have I mentioned how much I hate paint and body. It's the Devil!!
Could always throw a gear vendors on the 727 later if you change your mind about OD. Those things are kinda spendy though.
 
Ok throttle cable is fixed and I get 100% throttle. It also moves easier. Maybe it was in a slight bind before.
More driving and tuning and all I have to say is this MFer scoots!!!!
I found the rev limiter as expected. The cam really turns on around 3500 and doesn’t stop before my limiter.
As some have said, I finally have a big smile and it’s no where near done tuning.

When I first got my efi going on the 408, I said I’d never buy a carb again. I think I’ve lost my love for the 408 and I’ll never use one again.
 
Ok throttle cable is fixed and I get 100% throttle. It also moves easier. Maybe it was in a slight bind before.
More driving and tuning and all I have to say is this MFer scoots!!!!
I found the rev limiter as expected. The cam really turns on around 3500 and doesn’t stop before my limiter.
As some have said, I finally have a big smile and it’s no where near done tuning.

When I first got my efi going on the 408, I said I’d never buy a carb again. I think I’ve lost my love for the 408 and I’ll never use one again.
YES!!! It's a hard thing explain, but once you experience it.. Nothing else will ever feel the same. Glad you finally got that Hemi Grin
 
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Now to get the AC back up and running. It's HOT! I think I have my hose routing figured out, so I just need to order some fittings and hose to get it done.

I'm planning on going to autocross on 6/23, so that gives me a week and half to get that done and also make my catch can bracket so I can get that installed. I can't think of a better way to shake the car down than driving 70 miles to beat on it, then drive 70 miles back home...
 
One more piece of the puzzle knocked out. Whipped up a catch can bracket last night. I wanted to hide this somewhere badly, but it also needs to be serviceable so here it is. The bracket is made from a piece of 2" flat bar whittled into something that doesn't look like flat bar.


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Last week was a mad thrash to button up a couple small items and get the AC charged so I could get to autocross over the weekend. I was able to get everything done, then my O2 sensor failed. Fortunately, I was able to find one at a local auto parts, but of course the connector was wrong. Since the wires were the same color, I decided to just try to cut the wrong connector off and splice the correct one on. Luckily, it worked. My local SCCA is currently trying new venues and the one they are trying this month is 90 miles from my house. I figured 20-30 miles of test driving would be good break in for a 180 mile trip with some autocross in between, right? The car ran flawlessly on the way to the track. Coolant temp held steady at 190 degrees the whole way with the AC on. I was super excited to try out this course since it was a combination of normal parking lot autocross and the second half was on a section of road course with some long sweeping turns. My first run started great, until I hit the slalom. The combination of pressure and flow regulators I put in the pump did not work. I pretty much lost all steering assist with fast sawing of the wheel. I was very disappointed and frustrated. All the hustling to make it to that day and I couldn't even run. I packed my **** and drove home defeated. The good news (or not good news) is the heat index was 110 when I was driving home and coolant temp never got over 190 with the AC on. I took a different route home which was all interstate and cruised at 72-75MPH with no problem.
So here's what I put in the pump and maybe some gurus can offer some advice. I used the 800-850psi pressure reducer in the pump, the one Sublime sells. and I also used the Turn one 2.5gpm flow regulator. I realize this is the combo of parts he recommends for a steering box, but I used the same pump from the steering box on the rack and it worked fine. I figured matching that would be good. Obviously I was wrong. Once I got home and the car cooled off, I took the pressure regulator out and it had 2 shims totaling .060'. I took those out and tried it. sitting still sawing the wheel feels better. This was with the engine idling. Perhaps I just didn't have enough pressure? I'll find an empty parking lot and pretend I'm doing a slalom to see if it fixed it. I sure hope it will be this easy. I've found some mixed information online regarding what pressure a T-bird/M2 rack needs. I've seen 800 and I've seen 1200. Sublime's video on the pressure regulator mentions a Corrolla pump is around 1000. Maybe I need to get one of those to try it.
Oh well, I'm sure I'll figure it out eventually. Since everyone likes pictures, here' you go.

One more thing. The regulars at auto cross that know my car stopped in there tracks when they saw the hood open and were like, "That's new!"
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Last week was a mad thrash to button up a couple small items and get the AC charged so I could get to autocross over the weekend. I was able to get everything done, then my O2 sensor failed. Fortunately, I was able to find one at a local auto parts, but of course the connector was wrong. Since the wires were the same color, I decided to just try to cut the wrong connector off and splice the correct one on. Luckily, it worked. My local SCCA is currently trying new venues and the one they are trying this month is 90 miles from my house. I figured 20-30 miles of test driving would be good break in for a 180 mile trip with some autocross in between, right? The car ran flawlessly on the way to the track. Coolant temp held steady at 190 degrees the whole way with the AC on. I was super excited to try out this course since it was a combination of normal parking lot autocross and the second half was on a section of road course with some long sweeping turns. My first run started great, until I hit the slalom. The combination of pressure and flow regulators I put in the pump did not work. I pretty much lost all steering assist with fast sawing of the wheel. I was very disappointed and frustrated. All the hustling to make it to that day and I couldn't even run. I packed my **** and drove home defeated. The good news (or not good news) is the heat index was 110 when I was driving home and coolant temp never got over 190 with the AC on. I took a different route home which was all interstate and cruised at 72-75MPH with no problem.
So here's what I put in the pump and maybe some gurus can offer some advice. I used the 800-850psi pressure reducer in the pump, the one Sublime sells. and I also used the Turn one 2.5gpm flow regulator. I realize this is the combo of parts he recommends for a steering box, but I used the same pump from the steering box on the rack and it worked fine. I figured matching that would be good. Obviously I was wrong. Once I got home and the car cooled off, I took the pressure regulator out and it had 2 shims totaling .060'. I took those out and tried it. sitting still sawing the wheel feels better. This was with the engine idling. Perhaps I just didn't have enough pressure? I'll find an empty parking lot and pretend I'm doing a slalom to see if it fixed it. I sure hope it will be this easy. I've found some mixed information online regarding what pressure a T-bird/M2 rack needs. I've seen 800 and I've seen 1200. Sublime's video on the pressure regulator mentions a Corrolla pump is around 1000. Maybe I need to get one of those to try it.
Oh well, I'm sure I'll figure it out eventually. Since everyone likes pictures, here' you go.

One more thing. The regulars at auto cross that know my car stopped in there tracks when they saw the hood open and were like, "That's new!"
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I hate to hear that it wasn't the greatest time you ever had.. glad to hear it was good highway, hot day driving tho.

On my pump, I experimented alot to get to around 1000 psi and also use the same 2.5 flow regulator.. But I have a Borgeson box and I don't really do curvy track stuff either. I got pretty much closest to 1000 psi mark (Borg Recommended) with all of the shims except the thinnest one, removed from the Sublime valve. I do have a power steering analyzer that you are more than welcome to borrow.. pretty nice unit. Tells flow and pressure. BTW, I did find that my 2.5 flow, was a little light with this setup. You might need more flow.

I run a stock 6.4 PS pump.. Stock psi 1700 is what I was reading

I'll shoot ya one of them FB messages later
 
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