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Old 08-26-2007, 11:22 PM   #1
Green Machine
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Join Date: Jul 2004
Location: Estherville, Iowa
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GM 14097395 HT383/Ramjet HR Cam - Detailed specs here !!!

Short version - it is ground on a 109 LC and ground 3 degress advanced. Read below for more excruciating detail

Engine in the Green Machine is down at this time for a rebuild, but it is going back together, got the heads back on today, long story for another day. We are putting in a different HR cam to replace the very mild HR cam that was stock in that 305. I searched everything I could find on the 'net and called a few dealers, but could get almost all info on it except the intake and exhaust centerlines.

Most sites, but not all agreed it was ground with 109 lobe seperation, but no one (or place) could tell me if it was ground advanced or not. We went ahead and purchased a new GM HR 14097395 cam pulled from a Ramjet 350 from Ebay. Now most I'm sure would just bolt it in and go, but I had to borrrow a degree wheel and dial indicator so I could find out for sure.
Now why would any one buy such a small roller cam ? Because the stocker is even smaller !!! Stock for the 89 Camaro TBI roller is 179/195 @.050 with only .351 intake and .386 exhaust lift, should gain about 35 hp at 4500 rpm (peak) and 50 hp at 5000 !! With no torque loss anywhere !!! Cam was only $70 plus shipping on EBAY.
This should be a great cam to replace the stocker in any Vortec equipped truck also, I would think it is small enough not to affect the computer.

Here are the specs I found - note that lobes appear to be asymetrical on opening and closing sides. I did not take duration at lash point as that is pretty meaningless but GM says it is 288/308 - lift measured right on spec with .287/.300 lobe lift for about .430 and .450 at the valve.

Open and Close heights .004 .006 .050 .200

Intake Open 20-btdc 17-btdc 7.5-atdc 50-atdc
Intake Close 60-abdc 53-abdc 24-abdc 20-bbdc

Exhaust Open 63-bbdc 60-bbdc 35-bbdc 8-abdc
Exhaust Close 28-atdc 23-atdc 10-btdc 54-btdc



Here are some numbers distilled from the above that you can plug into you cam calculator to get close to the above actual opening and closing points.

.004 = 260/272 109Lc 1 deg ret

.006 = 250/264 108Lc 0 deg straight up

.050 = 196/204 109Lc 3 deg adv

.200 = 110/118 109Lc 4 deg adv

Hope that helps someone, I would have paid $20 extra to get the numbers on a real cam card.

Green Machine
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1968 C10 307 3spd Long Fleet ------ http://67-72chevytrucks.com/vboard/s...d.php?t=201103
1970 C10 305 Super T10 Long Fleet --- http://67-72chevytrucks.com/vboard/s...d.php?t=202285
1971 C20 383 TH350 Dana Posi ----- http://67-72chevytrucks.com/vboard/s...d.php?t=206894
2001 GMC Sierra 1500 C3 6.0

Last edited by Green Machine; 08-26-2007 at 11:32 PM.
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