1975 Imperial build thread

[1975.Imperial]

I am having the same issue with my mini starter. What was your solution? I'm going to the original rebuilt because I know it fits.

I got another mini-starter and put it in, it looked exactly the same as the first mini-starter, but this one just seemed to fit (the first would've also likely fit if I did it properly). I did take a little more care in installing it though, it does take some time to get it to fit right. I found that there was clearance for the "shim" to fit, it was just a pain to align properly. I recall having to get rather inventive with my socket extensions to get to the bolt and nut too.

Additionally, remove the terminal adapter that comes on the new starters, it interferes with the block. You'll need to tighten down the wires before installing the starter, once the starter's installed there's very limited/no clearance to fit a wrench or socket in there.

 

[1975.Imperial]

It's the dead of winter up here in Ontario and I'm suffering from the symptoms of classic car withdrawal, as such, I've started planning out projects for the Imperial this year.

One of the first projects I've been considering is getting the auto-dimming headlights to work. As of right now the system seems completely inoperative, I've fiddled around with the "eye" on the dashboard and the 'auto' on the headlight switch, they seem to do nothing. Has anybody here taken a dive into the system, if so, are there any recommendations you'd mind sharing with me?

I'm also trying to reduce wind noise from around the windows. After my vent-window conversion, it was made obvious that I didn't have the required weather stripping/cat whiskers for the conversion, and the rest of the weather stripping is at the point where it needs to be replaced. Could anyone direct me to a source for these? I'm aware there's some for where the windows meet the roofline, but I haven't heard of any reproduction cat whiskers, or new rubber for the section in between the front and rear windows.

I'm planning on covering the entirety of the floor in Eastwood's X-Mat to help reduce the sound from my new exhaust system. While I'm at it, I'll likely take apart the dash once again for access to the firewall, where I'll also be able to clean up some of my previous sloppy work.

In terms of performance, I'm still on the edge about getting a new Edelbrock carb and intake. I plan on replacing the nylon timing gear with an Edelbrock double-roller setup, so I might tack a couple extra parts onto that Edelbrock order. I'm currently thinking of going with the Performer RPM intake, either a 650 or 800 AVS2 carb, and a lower profile air cleaner (maybe an open element).

 

[1975.Imperial]

I've just realized that I never posted a sound clip of my new exhaust to this thread. Here it is, it came out sounding a bit different than what I expected, but I'm happy with it. It added a bunch of drone in the cabin, but I'm hoping that gets remedied with the addition of sound deadening, if necessary I may add a resonator. Performance increased dramatically, the previous 2-1/8" single exit exhaust was severely choking the engine, there's no signs of exhaust restriction present with the new setup. There's no noticeable drop in low end torque, I'd say there's an increase in power at all RPMs.

The details of the setup are: Rear exit dual 3" Mandrel bent H-pipe with Flowmaster 50 Series Delta Flow mufflers.

 

[CBODY67]

As for the intake manifold, there is an episode on the YT channel "318 will run" that clearly shows how to convert the factory spreadbore intake into a "normal 4bbl" intake with just a hand-held chop saw and some other hand tools. Not sure what kind of power you are looking for (or why), but anything "RPM" seems a bit out of whack for such a heavy car, where low-end and off-idle torque is needed. In most tests, the factory intakes are not that far off of what the Edelbrock's cost, it seems. I can sure take a $400.00 savings for about 1/2 hour or work! I know, leaning across the fenders with that heavy intake is something else, too, but I'd lean more toward the normal Performer and leave the factory insulator bag on the shelf. Instant "Air Gap"! BTAIM

Carb size, unless you're feeding a 514cid stroker, I'd lean more toward the 650 AVS2, for the supposed-to-be better lower rpm response it should have. It takes torque to move the car initially, not horsepower that only happens above 5000rpm. If you had a ZF 8-spd with the 4.50+ low gear ratio, so the engine could get spooled-up quickly, then the 800 might be more useable, to me. But then you'd need to adapt some of the earlier model year Imperial factory traction bars!

I concur on the double-roller timing set, but I'd lean more toward a real Cloyes product, myself. That way you know where it came from, rather than a set which EB co-opted and got their name put on it. FWIW

Just some thoughts. Your car, your money, your dreams.
Watch for the upcoming sales!
CBODY67

 

[1975.Imperial]

As for the intake manifold, there is an episode on the YT channel "318 will run" that clearly shows how to convert the factory spreadbore intake into a "normal 4bbl" intake with just a hand-held chop saw and some other hand tools. Not sure what kind of power you are looking for (or why), but anything "RPM" seems a bit out of whack for such a heavy car, where low-end and off-idle torque is needed. In most tests, the factory intakes are not that far off of what the Edelbrock's cost, it seems. I can sure take a $400.00 savings for about 1/2 hour or work! I know, leaning across the fenders with that heavy intake is something else, too, but I'd lean more toward the normal Performer and leave the factory insulator bag on the shelf. Instant "Air Gap"! BTAIM

Carb size, unless you're feeding a 514cid stroker, I'd lean more toward the 650 AVS2, for the supposed-to-be better lower rpm response it should have. It takes torque to move the car initially, not horsepower that only happens above 5000rpm. If you had a ZF 8-spd with the 4.50+ low gear ratio, so the engine could get spooled-up quickly, then the 800 might be more useable, to me. But then you'd need to adapt some of the earlier model year Imperial factory traction bars!

I concur on the double-roller timing set, but I'd lean more toward a real Cloyes product, myself. That way you know where it came from, rather than a set which EB co-opted and got their name put on it. FWIW

Just some thoughts. Your car, your money, your dreams.
Watch for the upcoming sales!
CBODY67

Thank you for the input. I watched that video (and a few others on his channel), it's interesting stuff.
As far as the intake manifold selection goes, I've done some research and it seems like the regular Performer intake is basically just a stock replacement that performs WORSE than the stock one. From what I've heard, the PerformerRPM still retains low-end torque, while improving top-end power, to me that seems like a win-win. I'm not aiming for this car to be a race car, but there's no reason it needs to be so slow.

I've decided to go for the 650 AVS2. Maybe sometime in the future I'll put a big stroker kit in, but you're right, 650 seems right for the street. I found a good source for one, but I'll have to wait until I'm in that area to get it. As for the hypothetical of a transmission and rear end gear swap, I've been looking at ways to mate a 46RH to a big block (that overdrive gear and lockup convertor would be very nice to have). Unfortunately that would take another couple thousand out of me, so that idea's going to have to wait

I'll look into Cloyes. I didn't have any doubts about an Edelbrock one, surely it would be better than the factory nylon-tooth set, but a better product certainly doesn't hurt.

As you can probably tell, I've got big dreams for this car, but maybe not the money to keep up.

 

[CBODY67]

As to intake manifolds, I've always considered the Performer intake to be a modernized version of the old CH4B Edelbrock intake of the late 1960s. It was that intake, plus the similar 383 DP4B version, that Chrysler put a factory part number on so it could be used in the stock classes at NHRA races. I don't know that I've seen a dyno test comparison of the Performer on a normal 440, vs a Performer RPM. Where did you find yours? As always, I'd be more concerned with torque output at less than 3000rpm rather than top end power, considering the car's weight.

What happens above 3000rpm is important too, but you have to get their quickly FIRST before the above 3000rpm power can happen. FWIW

Dreams and funding can be at odds, many times, so priorities and adjustments to the dreams can be the result.

Another consideration is to not set "the bar" impossibly high that getting there is not possible. Be reasonable and realistic as to what can be done, which should be very good, too, so disappointment is not overwhelming when the result happens. Remembering, too, that "for one thing to happen well", it can generate a need for other things to happen, too, so it is as well as it can be.

Just some thoughts,
CBODY67

 

[1975.Imperial]

Well, I think it was about time to replace this… I was expecting bad, but not this bad. Notice how two of the nylon teeth are completely missing. I counted 16 that were chipped too. That, combined with the slack in the chain, I wouldn’t be surprised if it had 50 more kilometres left until failure.
I have a cloyes c-3044 that should be coming in tomorrow.
I got all the disassembly done today in only a few hours, it was actually a pretty smooth procedure. I’m hoping it’s just as smooth going back together

 

[3175375]

Well, I think it was about time to replace this… I was expecting bad, but not this bad. Notice how two of the nylon teeth are completely missing. I counted 16 that were chipped too. That, combined with the slack in the chain, I wouldn’t be surprised if it had 50 more kilometres left until failure.
I have a cloyes c-3044 that should be coming in tomorrow.
I got all the disassembly done today in only a few hours, it was actually a pretty smooth procedure. I’m hoping it’s just as smooth going back together

View attachment 713911

View attachment 713912

View attachment 713913

I’m glad that you discovered this now!

 

[1975.Imperial]

I’m glad that you discovered this now!

So am I, I’m very glad that I didn’t discover this on the side of the road.

Late last season I heard a chattering/clicking sound coming from the engine upon letting off the gas after hard acceleration, I’m guessing the chain was so loose that it was slapping against the cover. I consider it a minor miracle that the camshaft was still pretty in time too.

I’m also guessing that with the new timing set, both my camshaft and ignition timing will be steadier. I’m looking forward to that little boost in performance.

 

[1975.Imperial]

Some more updates to report:
Starting off with the most current one: does anyone know of a reason why my driver's side speakers don't work? There's pops and buzzes but no music. I'm guessing it's just a stripped wire that has to be found, which I'm not overly excited to do.

I've been focusing on some driver-oriented fixes. I installed some Eastwood X-Mat sound deadening on the cabin floor. It helped a great deal in reducing now noticeable the exhaust drone is, although I will eventually have to install some in the trunk to reduce the drone even further.

I got my air conditioning working again. Last time I charged the system, the Red Tek 12a adapter didn't like to seal and leaked out all my refrigerant. To my surprise, the AutoTemp works, as long as I turn it onto high-defrost before selecting another setting, if I don't do that it doesn't turn on. Looks like I'll be tearing the dashboard apart again to reinstall my A/C ducting.

I confirmed my speaker issue today as I was installing some new speakers, I was hoping that the old speakers just happened to be bad on the driver's side, but it turns out the issue's a rooted a bit deeper than that. On the subject of radios, my car's radio doesn't like to hold a station. It would be nice if it didn't do that, but I'm not sure I want to put the effort in to this radio to fix it. As this is my daily driver and I'm more of a fan of my Spotify playlists than the local radio stations, I'm heavily considering getting a touch-screen head unit.

I've also made the decision to reinstall my non-vented windows. It was nice to have them for a bit, but I ran into complications with the vents causing interior squeaks and rattles, wind noise from old seals, and the inability to adequately adjust the door glass alignment. I do like the unobstructed view from the ventless windows too.

One of my upcoming projects will likely be to get rid of this annoying wind noise. I'll be needing new catwhiskers, weather stripping, and front-to-rear window seals. If anyone has a source for those, I'd love to hear it. I also need new sunroof cables but I'm not sure where to get them either.

Underhood I've done a cooling system flush, although I'm not sure that was needed as I was having trouble getting the car up to operating temp. Even with a full grille block it wasn't getting there, the recent warm weather definitely helps it though, today I took the rest of the grille block out with no issues.

I'm happy for the warm weather for other reasons too, notably that I can postpone dealing with my choke issue. I've identified that the electric choke controller is inoperative. I'm on the fence on what to do, I could buy a used controller for $250ish and use it until it dies. I could make my own choke controller, although since I removed the heat riser from my exhaust manifold there's a concern if that will work at all. Or I could get myself the Edelbrock carburetor that I've been wanting for a while. My carburetor's throttle shaft bushing is also worn out to the point of being musical, so I don't really want to dump more money into this worn out carb. Thankfully I can live without a choke while the weather's warm.

I finally took the time to set my timing again since installing the new timing chain, now I need to run supreme...

My brakes were spongy so I re-bled the rear, now they're back and working great! I am a bit concerned though as the rear brakes went soft and then the reservoir ran out of fluid, this was about a week ago, I thought it was a leak, but I couldn't find any evidence to indicate a leak anywhere. Regardless I checked my connections although all seemed good. I just had this master and booster rebuilt last year for more than a pretty penny, so I'm hoping the fluid's not draining into the booster, although that's normally an issue with the front brake reservoir. I guess I'll have to monitor the fluid level and proceed as needed.

Tomorrow I plan on finishing up the speaker install, hopefully track down the issue with that, and give the car a nice bath.
As always, any opinions/advice are appreciated

 

[CBODY67]

Thanks for the updates!

"Station drift"? The good part is that the same basic mounting system for your radio was common for Chrysler Corp radios into the 1980s, so used radios should be available. Only thing is that the 1980s versions are wired for "1-wire" rear speakers, so an extra wire has to be run at the speaker to ground the speaker. As the existing ground wire might be grounded up front somewhere? Finding one of the "silver-faced" ETR radios from the middle 1980s that still works would be neat.

Choke controller? Used to be that Holley had a "Choke Thermister" that was basically a variable ground that was heat modulated. It was the ground for the integral electric chokes on their electric choke carburetors. I bought one, but seems I did not need it as it made no difference for me down here. Not sure if they still sell them, but something of that nature might be easier to build than not? The ground eyelet was big enough to go under an intake manifold bolt head.

Is the existing choke assist item a timer or thermister? If it is just a timer, might be able to re-purpose the EGR timer module?

How MUCH base timing are you running that an 8.2CR motor needs high-octane fuel?

Muffler drone? What mufflers are causin that? Just curious.

Enjoy!'
CBODY67

 

[1975.Imperial]

Thanks for the updates!

I was not aware that ETR radios would "station drift". The good part is that the same basic mounting system for your radio was common for Chrysler Corp radios into the 1980s, so used radios should be available. Only thing is that the 1980s versions are wired for "1-wire" rear speakers, so an extra wire has to be run at the speaker to ground the speaker. As the existing ground wire might be grounded up front somewhere?

Choke controller? Used to be that Holley had a "Choke Thermister" that was basically a variable ground that was heat modulated. It was the ground for the integral electric chokes on their electric choke carburetors. I bought one, but seems I did not need it as it made no difference for me down here. Not sure if they still sell them, but something of that nature might be easier to build than not? The ground eyelet was big enough to go under an intake manifold bolt head.

Is the existing choke assist item a timer or thermister?

How MUCH base timing are you running that an 8.2CR motor needs high-octane fuel?

Muffler drone? What mufflers are causin that? Just curious.

Enjoy!'
CBODY67

The station drift is very real, there's about a 5.0+- variation between what the displayed station is and the station that's being picked up. I was aware of the 1-wire speakers in the rear. I have the ground wires ran to pre-existing holes in the package tray metal. That's what the FSM wiring diagram seemed to direct, and it's worked for the passenger side, although I'm suspecting another issue on the driver's side. The front speakers have both a + and - cable. I also discovered, although most literature online suggests the front speakers are 3.5", in reality they are 5.25", magnet size may be a factor to account for, on the driver's side there's a wiring harness that interferes with the fit. I'll be trying to relocate that harness tomorrow.

Choke controller, the little 2-pronged box that controls when and how much current is passed to the choke's coil. I may very well go down the path of making my own or adapting something to fit. I believe the existing one relies on temperature, so not a timer, although the DIY replacement ones I've read about rely on a timer instead.

As for timing, I'll have to check with my timing light, I set it to the highest vacuum. I also have a FBO limiter plate, which allows for about 10 degrees on mechanical advance, I also changed out the springs to probably the equivalent of 2 factory light springs. I've disabled all emissions equipment, meaning the vacuum advance is now hooked to manifold vacuum, although it's not set very high (I'd have to check with my timing light for exact numbers).

I've had my whole exhaust redone from the manifolds back, dual 3" mandrel bent H pipe with Flowmaster 50 Series Delta Flow mufflers. See my above post for a sound clip and a writeup in the description of the video.

 

[CBODY67]

Thanks for the information.

Rear speakers -- When I did the upgrade to a factory stereo in my '80 Newport, I just ran a jumper wire from the unused speaker lug to the nearest mounting screw for the speaker. Simple and generally unnoticed. GM used internal-ground speakers for those situations.

Timing -- Even with far too much spark timing, clatter can occur even with a 8.2CR motor. Factory OEM was to run the vac advance from the PORTED vac port on the carb, not manifold. You really need to use a timing light rather than a vac gauge! Usually 12-15* BTDC at hot base idle. With the "too light" advance springs and such, that is why you are needing the fuel octane you do.


With manifold vac, you are getting the initial timing, plus the full vacuum advance at idle. Might feel great, but unless the carb is set-up for that, in where the hole for the idle discharge ports and transition ports are drilled into the throttle body, which relates to idle speed and the resultant relationship of the throttle plates and holes at idle, issues of off-idle flat spots and such can easily occur. I also experimented with one of my cars, which I bought new, which I later learned was configured to use manifold vac to run the vac advance, OEM. I left it that way as that is how it was supposed to be, OEM. So, my simple recommendation is to run the vac advance from the ported vac port, OEM. Then re-set the hot base idle to or near factory spec rpm and the base timing to 15* BTDC max. Might need to install ONE "medium" mechanical advance spring to slow the mech advance a bit, if clatter persists. A little bit of trace rattle at part throttle or going up-hill is not too bad, but better to keep everything quiet.

Take care,
CBODY67