Did a Bit of Tuning Tonight.....

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ramcharger

ramcharger

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OK, here's the build in my Ramcharger:

360 LA block bored .040 over
Block decked for zero P to D height
Stock crank turned .010 under
Eagle I beam rods
KB hyperutectic flat tops
Cop car heads milled to 68cc, 2.02 intakes, pocket ported by me.
10.2:1 measured comp ratio with a Cometic .040 gasket with 4.100 bore.
Lunati Voodoo Cam:
Advertised Duration (Int/Exh): 256/262
Duration @ .050 (Int/Exh): 213/220
Gross Valve Lift (Int/Exh): .454/.475
LSA/ICL: 112/108
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1000-5500
Part Number: 60401
Crane Gold 1.6 Rockers and shafts.
Crane springs, retainers and locks. I can't get the specs as they have been taken over by S&S Cycle (Not a bad thing in my view), but the springs were installed as recommended by crane with a IIRC 110 lbs seated and 300 lbs @ .500 lift.
Weiand Action+ Dual Plane Intake manifold, no spacer.
Holley early (no power valve on secondary metering block) model 4777 4150 style carb 650 double pumper.

Here's my tuning specs:
12 degrees intial with 34 total all in by 2500 rpm (MP distributor).
Ran it with the vacuum advance, but I disconnected it as pedal feel and cruise pedal position was not affected.

I am running a .032 primary squirter and .028 secondary squirter.
74 primary jets and 76 secondary jets.

OK, here's my driving impressions. Absolutely stellar off-idle and highway passing performance in a 5500 lb full time 4wd truck at 5900' altitude. If I floor it going up a hill @ 6000' + and slap into 2nd at 70 it just freakin' moves and lets out a howl that makes people freak, lol! But here's the deal, it starts to lay over @ 4800 and does the "snap, crackle, pop" at about 5000 rpm.

Lunati says this cam is good to 5500, but this is, of course, an LA cam that spreads the spectrum from to 273-360 ci. I think it's valve float.

Here's the question:

I had a Comp XE262 in a lower compression (stock) 360 with their recommended springs and installed as recommended and it did the same thing. Am I asking too much on the top end for such a small cam in the rare air here? Should I just quit my complaining and just keep smokin' every Chevy/Ford/Toyota pickup that comes my way? Should I swap to Lunati's true dual springs as valve float may be my true problem? Am I insane for blasting my full time 4WD Ramcharger to 100 MPH on the entrance ramp to figure this out? Muwhhahahaha!
 
I live at around 4000ft and some times my Dart acts up on me above 3000 rpm. I put a carb spacer on it and it has not done it sence. It has allways run good down the hill though. One time I was down the hill running at 5500 doing 120 mph. But up here in the hills it acts up some times. Sorry I have not found out why yet. But for some reason the 1/2 inch open Penolic carb spacer has been helping so far. I need to reajust the carb because I now have a stumble off of idle now. Back to tinkering. LOL
 
hmmm. I am by no means an expert but i would think your open spring pressure should be closer to 350 or 360 @.500? last chebby we did was .510 and I seem to remember them being somewhere around there. with the 1.6 rockers that puts you a little over .500 lift so maybe you do need the stiffer springs. I have the same cam in my 318 but with 1.5's and it will pull up to about 6,000 r's till its out of breath. are your springs number 69308-1?
 
Burntorange70 said:
I live at around 4000ft and some times my Dart acts up on me above 3000 rpm. I put a carb spacer on it and it has not done it sence. It has allways run good down the hill though. One time I was down the hill running at 5500 doing 120 mph. But up here in the hills it acts up some times. Sorry I have not found out why yet. But for some reason the 1/2 inch open Penolic carb spacer has been helping so far. I need to reajust the carb because I now have a stumble off of idle now. Back to tinkering. LOL
Click to expand...

I had a LD4B manifold on it previuosly with a 1" alum open spacer. Great manifold but the carb would boil over on "bumps". Same problem though....layover @ 4800 rpm and snap, crackle, pop over 5K.

BTW, a phenolic spacer is in the works to solve the splash/boil 4x4 problem I was having. :)

camd64 said:
hmmm. I am by no means an expert but i would think your open spring pressure should be closer to 350 or 360 @.500? last chebby we did was .510 and I seem to remember them being somewhere around there. with the 1.6 rockers that puts you a little over .500 lift so maybe you do need the stiffer springs. I have the same cam in my 318 but with 1.5's and it will pull up to about 6,000 r's till its out of breath. are your springs number 69308-1?
Click to expand...

I'm sure I could dig out the receipt, but it was a Crane single spring with a damper for a Crane 218/228 cam. The Lunati recomended true dual spring is much closer to 350 lb. :) And yes, you are correct, the lift of the lunati is .506 on the exhast side and .484 on the intake with a 1.6 rocker..... By no means a radical cam and I'm thrilled by it's performance and torque in a street driven full time 4x4. :)
 
I think you have the same springs i do, they spec out at 113 @ 1.60 and 280 @ 1.150. yeah i've heard your beast and does it sound burly! now the only question is when is the in truck video coming, maybe that entrance ramp.......
 
camd64 said:
I think you have the same springs i do, they spec out at 113 @ 1.60 and 280 @ 1.150. yeah i've heard your beast and does it sound burly! now the only question is when is the in truck video coming, maybe that entrance ramp.......
Click to expand...

Yep, sounds like the same springs...:)

I'll see if I can get Doktorx to hold the camera, lol!

The tank in the truck was full when I was employed, then I kept removing the the AN fitting, switching on the electric fuel pump and stealing fuel for the Jeep, lawnmower, weedwacker, etc. :) I fired it up today and realized that there was still good fuel in it, lol! Time have a bit of fun and not a cop in sight...... :snakeman::snakeman:
 
Here's a few pics of what i'm talking about...

P1010137.jpg


P1010639.jpg
 
Those spring pressures are right in line with where they should be. Were the springs tested or just installed per the specs?
 
ramcharger said:
I'll see if I can get Doktorx to hold the camera, lol!
Click to expand...
I think that could be arranged. I might bring a tripod to minimize acceleration-induced camera shake. This will serve the secondary purpose of flaunting my super-low-budget Jeep Cherokee and the monster dogs could probably do with some torment. I'll grab some beer in moustache-friendly containment vessels. 8)
 
crackedback said:
Those spring pressures are right in line with where they should be. Were the springs tested or just installed per the specs?
Click to expand...

Just installed per Crane's specs. :)

doktor_x said:
I think that could be arranged. I might bring a tripod to minimize acceleration-induced camera shake. This will serve the secondary purpose of flaunting my super-low-budget Jeep Cherokee and the monster dogs could probably do with some torment. I'll grab some beer in moustache-friendly containment vessels. 8)
Click to expand...

Sounds good Dok!

CHEATHAM said:
sounds like a carb jetting issue
Click to expand...

I'ts most certainly not a primary jetting issue as it runs stellar around town and on the higway with instant response. Since it's a dbl pmpr, I can feel when the secondaries open through the pedal. No hesitation whether I ease into it or slam 'em open. Plugs look good. I have tried going richer on the secondaries and just start getting a bog when the secondaries open. I may try going two sizes leaner and see what happens, that will bring my jetting "square" with 74's all around.
 
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