Next stage for my 360 build?

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MopaR&D

MopaR&D

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Some of you guys may have seen my posts regarding the 360 buildup for my Duster. The current plan is Magnum heads (still debating buying the tools to do some porting/chamber work), reusing my Lunati Voodoo 256/262 cam (http://www.lunatipower.com/Product.aspx?id=1543&gid=287) with the 1.6:1 Magnum rockers, KB-107s, RPM Air-Gap Magnum intake, Doug's headers, and Carter AFB 625 cfm. First question is, about how much HP and torque should it make AND around what RPM in this form?

Currently my plan is also to rebuild my A-904 with a shift kit and 11" PTC converter and 999 low gear set, with 3.07:1 gears in an 8 1/4" rear. However I REALLY REALLY want a manual transmission and I'm keeping an eye out for the McLeod 5-speed that was supposed to come out six months ago... So with a future swap to an OD manual and subsequent re-gearing (3.73 or 3.91) I'd also like to bump up the 360 into a more serious engine. First thoughts are ported Eddy's and a solid cam, which brings me to my next question, how much HP and RPM can the stock crank and rods handle? And is there a solid cam out there that can still be practical on a 95% street-driven car? I just want to be able to rev this thing out to 7000 because, frankly, nothing on earth (man-made) sounds better than a screaming Mopar V8. I know some of you will say STROKER to get more power but this 1979 block is already 0.060" over and I don't want to risk cylinder wall flexing more than I already am.

And sorry for the huge post, for some reason it's difficult for me to condense my thoughts as well as the rest of you.
 
how much HP and RPM can the stock crank and rods handle? And is there a solid cam out there that can still be practical on a 95% street-driven car?
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Well, yea, a solid cam can be stretable no problem, it's more of the duration of any cam that becomes a issue of streetabilty. And about reving to 7,000, not a good idea unless you prep that set up to go there, which makes me wonder, what cam is going to slide in that would be making power at 7.000 rpm? And he considers this streetable?
Waaaaaaaat ever..........

The stock crank can safely go to 550 HP no issue. Going further can be done. I've seen and read 600 hp, but I'd rather have a forged unit if I'm going to build something that stout.
 
Well I just had some trouble finding "milder" solid cams, the only company I've seen yet is COMP. I'd like another Lunati but all their solids are pretty radical. You said "prep the rest of the setup to go there" what else exactly would I need? I'd probably match the cam and heads with a Torker or other single-plane intake, although my RPM Air-Gap is supposed to go to 6500 (not too far off). I know I'd need some good adjustable rockers too, maybe PRW's stainless steel set? And regarding "streetable" I would need the engine to be able to cruise at ~3000 RPM and not be so far 'under the cam' to be spewing unburned gas out the exhaust (bad gas mileage) and struggling to get up a small incline.
 
He means build the basement before you decorate the penthouse.
 
A MP .509 cam in a 340 will pull 7K with a 4 speed, one here in town running high 11's on street tires. Lots of cams will do it, just gotta pick one.
 
What does the bottom end need to live there? Better connecting rods? Would hyper-eutectic pistons be able to rev that high in a 360? I wouldn't expect it to make more than 450 HP or so...
 
Theres oiling mods that need to be done for 7,000 rpm.
That purple 292/.509 makes peak power at 6500 or less.
You'll be hard pressed to run 7000 grand and actually make power that is useable.

The best way to go about building a great lower end is to have an expert machinest work on it and use quality parts. While stock parts can do it, it takes extra effort in mahining them.

If I was building a 7000 rpm scream machine, it would be with a forged crank, serious con rods and have the machinest know i'm looking to build a high reving 550+ hp machine.
 
So basically there's no point revving it that high unless I want to make 500+ HP? (sigh) fine... lol. What about the solid cam though? Any of you guys tried running a 'moderate' solid cam on the street with 'moderate' gearing/converter? How often does the lash have to be set, and stuff like that?
 
I will be running a 11-1 aluminum headed 360 with a solid cam @ 248 @ .050, 4spd, 4.10, 27 inch tire in a 73 Cuda. Everything from the intail and test point so far feels very good and I would recomend this car to my Mom. (She's 64 by the way.)
I just put the RPM air-gap on it, so it should feel a little better down low. I had a single plane and a 750 Carter.

A bit radical on idle, but it does start rolling well and easy from a stand still without "To big cam blues issues" Alot of how the car is, is in how well you tune it.

You really shouldn't have to adjust the rockers beyond intail set up and final check for a long time. When you get used to the extra noise the mech. valve train has, you adjust it when she clatters.
You could perform spring and fall time checks with the feeler gauge. I bet it'll be a long time before you adjust them.
 
In order to make power at 7000 rpm, everything has to be working togther for it. Chances are, the cam you'll need to use won't start making anything in power to a min. of 3500 rpm. This is way beyond your spec for cruising.

To help bridge the gap or, I guess I should really say widen the rpm range, use a Hyd. Roller cam for more of a RPM spread. I would look a split duration cam of about 230 intake duration. This, in general has a starting RPM of 2000. And should settle into a cruise RPM of about 3 grand easy.
 
Hmm I don't think I'll be 'going roller' anytime soon. I'll probably still get a solid flat-tappet with a reasonable power range, like this. I just wanna have that bad-*** old school 'tick-tick-tick' sound and an engine that likes to rev. BTW you should post a video of your Cuda, that 360 sounds like it's pretty serious.
 
That would be an excellent cam to use. I started to type out two sets of duration when I replied, but sided on the K.I.S.S. side for a reply. That duration (236 for an intake duration @ 050 ) is what I started to type in for a max size I'd run with.

Videos of the car will happen next spring maybe. I have a bunch on the plate with school kids and collage etc...... LOL it never ends.
I still need to put back together the front end, get a windsheild and re-wire or replace the main wiring harness under the dash. It's a bit far from driveable and to be honest, I don't wanna do a video of a static engine, but would rather a few rippin burnouts shown in and outside the car along with a few high spedd runs past the cam.

I figure, if your gonna do it, do it right or not at all.
 
VERY cool. And you're definitely right, burnout and in-car videos are so much better than just 'idle and rev' stuff...
 
I wouldn't want to run a 360 with stock rods and crank to 7000RPM. The good news is that you don't have to buzz it that high to make power. My 340 could go to 7000, but it makes peak horsepower at 6000, so I shift at 6400. By the way, it's a hydraulic roller with .530 lift and 230 duration at .050.
 
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