1974 Roadrunner 360 Sunroof KB5 Blue

[Root2812]

This looks so good! It's coming out nicer than expected.

I got an interesting and exciting call last night. My dad had my car at his shop a few hours away because I needed help with broken bolts and I haven't been able to go get it. I know he has done alot of work to it and it still needs a carb rebuild. So he calls me last night kinda excited and said the car was fun but that something wasn't quite right so he played with the jets. Now he says the car is fast and will throw you back hard. I thought it was fun when I had it so I'm excited to get behind the wheel again.

That got me thinking.. I test drove a 73 RR last year with a 340 and it was a ton of fun and I assume the 360 should be close to that since the 360 is rated at 5hp more. So if the engines are so similar why does it seem like slot of the posts I see are people saying the 340 is better than the 360? Is it just preference or is there a real rationale. I just wondering here.

 

[Root2812]

View attachment 342469 got to love the super rare and hard to find sunroof cars

Yeah that was one of the things that sold me on this exact car. The sun roof makes it unique. I just hope I can get mine open someday.

 

[plymouthman72]

That is a good debate and you will get a million different opinions. They are very similar engines but the 360 is much much cheaper to build from what I have been told which is a good thing. If I didn't have a 340 already in my car, I would go with a 360 to save money. From what I have read in a nutshell, the 360 has more torque but the 340 winds up faster and can go to higher rpms. Mine came with it but I like the "cool" factor of having the 340 but both are great engines. Then you have those that say a b body is to big for a small block and that you should trade up to a 440

 

[Root2812]

I have never owned a big block in anything so I have no comparison but looking just at stock advertised numbers the 360 was only 5hp less than the 400 big block so I would think the weight trade off would negate the benefit there. I forget what the 440 was rated at in 1974.

 

[Bb70charger500]

I think the 440 was rated at only 230 ish in 74 .the 360 is a great eng I prefer small block cars over big block. I've driven a 440 4 speed 72 charger and a 340 4 speed 72 charger and the power was only off by about 60 h.p. but the way the 340 responded compared the the 440 I'll give up the 60 HP also the 440 makes for a very nose heavy car pain in the *** to corner at any bit of speed it makes the car tail happy the 340 or small block car is much more manageable and in my opinion street able . I like to Auto cross the old cars every now and then the 440 makes to much of a mess taking cones out the lighter set up make cornering much easier . I've had 318,340,360 and deff not to expensive to build but using a stock platform the 318 become useless but a great driver motor I've squeezed 290hp to the wheels for not alot of money. The 360 and 340 can make big power 360 cheap to a point . 340 is expensive only to get your hands on the basic parts Block crank heads ext. If I didn't have the 340 already I'd go 360 deff. Not to much difference if you know what your doing.

 

[Root2812]

I need some help from you guys. As you can see in my pictures my interior is trashed and all the plastic parts are chalk. I found a local guy who would sell me the kick panels, a-piller covers, and lower front and rear door panels from a 72 SSP he parted out. He also has some of those parts from a 73 charger. I can get all those plastic parts I need for $300 but I don't know if they all interchange since I see some variability in other things. I am only getting those plastic parts for now.

 

[plymouthman72]

Lower door panels, kick panels and a pillars should be a direct fit. Upper door panels I think should. The only difference I think is in the sail panels?

 

[Root2812]

Great, that is what I was thinking but wasn't sure. My sail panels are good and I am keeping my upper door panels. I will still need seat backs at some point but piece by piece is ok by me.

 

[Bruzilla]

Lower door panels, kick panels and a pillars should be a direct fit. Upper door panels I think should. The only difference I think is in the sail panels?

Sail panels from the SSP will fit. If they are from the Charger, it depends on if it was the model with the sloped rear window. Those won't fit. If it was one with the same rear window as the Satellites, it will but the center detail will be different. The detail area for the Satellite panels had square edges and the Charger's had rounded edges.

 

[Bruzilla]

I have never owned a big block in anything so I have no comparison but looking just at stock advertised numbers the 360 was only 5hp less than the 400 big block so I would think the weight trade off would negate the benefit there. I forget what the 440 was rated at in 1974.

The benefit comes from potential HP. Yes, you can mod the crap out of a SB to get the numbers up, but you can accomplish more for less with a BB. Of course, that only matters if you have a need for HP. I don't race my cars, but I don't like coming in second to a ricer when coming out of a stop light either.

I also like the panache factor quite a lot. The 440 was the top dog engine for these cars, and having a SB just seems like marrying a beauty queen and having her wear baggy clothes all the time.

 

[Root2812]

So I'm starting to look at wheels. I thought I would buy the back two first. I'm looking at wheel vintiques 15x8 mopar rally wheels with a 275/60/15. They offer a few back spaces to choose from. What should I choose for this set up? 4.5?

 

[Root2812]

No response in rear rim back space?

Anyway, I took the car for my first 30 miles around town this weekend. My dad has about 400 on my car but this is the first I have really gotten to drive it. It went well except that it clogs up inline fuel filters really fast. I think I'll have to pull the tank but with regular filter swaps I should be able to hold off for a while. My carb has a problem. Sometimes the choke sticks. One time I started it and it idled at 3500rpm so I shut it off, played with the linkage, and then restarted it and it was fine. Sunday I went for a drive and stopped to eat. Then the car wouldn't start at all. I waited a minute and then played with the linkage and then it ran good. I kno nothing about carbs beyond my lawn mower. Any ideas what to try? It's a Holley.

Also, where are you guys getting carpet from? The legendary website sucks and I couldn't find carpet. I found it on year one but they have two different black 2 piece carpets for a 74 automatic. What's the difference? Can infer 1 piece? Where is a good source?

My interior is gross so that is where I am going to focus next after I get it running well.

 

[Root2812]

Well my last two questions have gone unanswered but maybe the third time is a charm. I was out working In the car and saw a small gas leak from the carb that had been epixyed over. I pealed the epoxy off and it started to hemmorage gas. I put some silicone on it for now until I can figure it out. It's leaking right out of the top of the bowl. I then realized that I was missing the vent rod, see item 22 on page 5 of this if you don't know what I am talking about. http://documents.holley.com/199r8340-1rev.pdf

My leak is coming from the boss on top of the bowl by the vent valve. Can anyone explain to me what I should do and where I can get the missing piece?

And if anyone can help, how can I trouble shoot my tach? It's not accurate and seems to vary on how far off it is. At least it sounds off to me.

 

[drobertson]

I think the 440 was rated at only 230 ish in 74 .the 360 is a great eng I prefer small block cars over big block. I've driven a 440 4 speed 72 charger and a 340 4 speed 72 charger and the power was only off by about 60 h.p. but the way the 340 responded compared the the 440 I'll give up the 60 HP also the 440 makes for a very nose heavy car pain in the *** to corner at any bit of speed it makes the car tail happy the 340 or small block car is much more manageable and in my opinion street able . I like to Auto cross the old cars every now and then the 440 makes to much of a mess taking cones out the lighter set up make cornering much easier . I've had 318,340,360 and deff not to expensive to build but using a stock platform the 318 become useless but a great driver motor I've squeezed 290hp to the wheels for not alot of money. The 360 and 340 can make big power 360 cheap to a point . 340 is expensive only to get your hands on the basic parts Block crank heads ext. If I didn't have the 340 already I'd go 360 deff. Not to much difference if you know what your doing.

A big block can weigh nearly the same as a small block, if the big block is using aluminum heads, intake, water pump, etc. Maybe even less than an iron headed small block.

 

[Photon440]

I put some silicone on it for now until I can figure it out. It's leaking right out of the top of the bowl. I then realized that I was missing the vent rod, see item 22 on page 5 of this if you don't know what I am talking about. http://documents.holley.com/199r8340-1rev.pdf

Are you also missing parts 23, 24 and 25? The missing rod alone shouldn't cause a leak. And I hope you use a gasoline resistant silicone as most regular silicone sealant dissolves in gas. It would probably be easier to find another fuel bowl without the vent (both types shown in the link you supplied).

 

[drobertson]

From what I understand, the stock rear of these 71-74 b bodies can fit a 10" wide wheel with 4.5" backspacing and a 295 width tire. I wouldn't go any wider, as rubbing may result.

 

[Root2812]

Are you also missing parts 23, 24 and 25? The missing rod alone shouldn't cause a leak. And I hope you use a gasoline resistant silicone as most regular silicone sealant dissolves in gas. It would probably be easier to find another fuel bowl without the vent (both types shown in the link you supplied).

I have those parts. It's leaking from the raised part next to that with no part id in the picture. I did use a fuel safe silicone and it stopped the leak for now. What does that missing part do?

 

[Root2812]

From what I understand, the stock rear of these 71-74 b bodies can fit a 10" wide wheel with 4.5" backspacing and a 295 width tire. I wouldn't go any wider, as rubbing may result.

Thanks. I was only going to use a 8" wheel out back with a 275 tire. Would the back space still be 4.5"? I just don't want to order rims and have the wheels be too far in or too far out and look stupid.

 

[drobertson]

Thanks. I was only going to use a 8" wheel out back with a 275 tire. Would the back space still be 4.5"? I just don't want to order rims and have the wheels be too far in or too far out and look stupid.

I believe the backspacing would be the same, but I'm not 100% sure. Maybe somebody else can pitch in with more info.

 

[Root2812]

Can anyone else chime in on the wheel back space? I am sure a lot of people here have run an 8 inch wheel.