: Northstar Cam specs



AJxtcman
11-11-07, 05:45 PM
Cadillac specs


1993 - 1998 Cadillac (LD8 (VIN Y )
• Valve Timing (With Ramp at 0.100 mm Lift)
• Intake Opens 9 degrees BTDC
• Intake Closes 55 degrees ABDC
• Exhaust Opens 51 degrees BBDC
• Exhaust Closes 13 degrees ATDC

• Valve Lift
• Intake 8.6 mm 0.339 in
• Exhaust 8.6 mm 0.339 in

• Duration (@ 0.100 mm Lift)
• Intake 244 degrees
• Exhaust 244 degrees

• Valve Overlap (@ 0.100 mm Lift) 22 degrees

.

1993 - 1999 Cadillac (L37 (VIN 9)
• Valve Timing (With Ramp at 0.100 mm Lift)
• Intake Opens 13 degrees BTDC
• Intake Closes 73 degrees ABDC
• Exhaust Opens 51 degrees BBDC
• Exhaust Closes 13 degrees ATDC

• Valve Lift
• Intake 9.4 mm 0.370 in
• Exhaust 8.6 mm 0.339 in

• Duration (@ 0.100 mm Lift)
• Intake 266 degrees
• Exhaust 244 degrees

• Valve Overlap (@ 0.100 mm Lift) 26 degrees

.

1999 Cadillac (LD8 (VIN Y )
• Valve Timing (With Ramp at 0.100 mm Lift)
• Intake Opens 8 degrees BTDC
• Intake Closes 55 degrees ABDC
• Exhaust Opens 51 degrees BBDC
• Exhaust Closes 13 degrees ATDC

• Valve Lift• Intake 8.6 mm 0.339 in
• Exhaust 8.6 mm 0.339 in

• Duration (@ 0.100 mm Lift)
• Intake 243 degrees
• Exhaust 244 degrees

• Valve Overlap (@ 0.100 mm Lift) 22 degrees

.

2000 - 2003 Cadillac (LD8) 1.68 Rockers
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Exhaust 236 degrees
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Intake 242 degrees
• Camshaft Lobe Lift - Exhaust 5.94 mm 0.2339 in
• Camshaft Lobe Lift - Intake 6.15 mm 0.2421 in

• Camshaft Lobe Overlap @ 0.150 mm (0.006 in) Lift 1.98 degrees

• Camshaft Timing @ 0.150 mm (0.006 in) Lift
• Intake Opens 5.6 degrees BTDC
• Intake Centerline 113.0 degrees ATDC
• Intake Closes 236.8 degrees ATDC
• Exhaust Opens 222.5 degrees BTDC
• Exhaust Centerline 107.0 degrees BTDC
• Exhaust Closes 13.8 degrees ATDC

.

2000 - 2003 Cadillac (L37) 1.68 Rockers
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Exhaust 246 degrees
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Intake 251 degrees
• Camshaft Lobe Lift - Exhaust 5.94 mm 0.2339 in
• Camshaft Lobe Lift - Intake 6.15 mm 0.2421 in

• Camshaft Lobe Overlap @ 0.150 mm (0.006 in) Lift 2.04 degrees

• Camshaft Timing @ 0.150 mm (0.006 in) Lift
• Intake Opens 0.0 degrees ATDC
• Intake Centerline 122.0 degrees ATDC
• Intake Closes 251.0 degrees ATDC
• Exhaust Opens 225.5 degrees BTDC
• Exhaust Centerline 106.0 degrees BTDC
• Exhaust Closes 20.5 degrees ATDC
.


2004 - 2008 Cadillac (LD8) 1.68 Rockers
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Exhaust 236 degrees
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Intake 242 degrees
• Camshaft Lobe Lift - Exhaust 5.94 mm 0.2339 in
• Camshaft Lobe Lift - Intake 6.15 mm 0.2421 in

• Camshaft Lobe Overlap @ 0.150 mm (0.006 in) Lift 1.98 degrees

• Camshaft Timing @ 0.150 mm (0.006 in) Lift
• Intake Opens 1.3 degrees BTDC
• Intake Centerline 117.0 degrees ATDC
• Intake Closes 237.9 degrees ATDC
• Exhaust Opens 226.1 degrees BTDC
• Exhaust Centerline 111.0 degrees BTDC
• Exhaust Closes 5.1 degrees ATDC

.

2004 - 2008 Cadillac (L37) 1.68 Rockers
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Exhaust 246 degrees
• Camshaft Lobe Duration @ 0.150 mm (0.006 in) Lift - Intake 251 degrees
• Camshaft Lobe Lift - Exhaust 5.94 mm 0.2339 in
• Camshaft Lobe Lift - Intake 6.15 mm 0.2421 in

• Camshaft Lobe Overlap @ 0.150 mm (0.006 in) Lift 2.04 degrees

• Camshaft Timing @ 0.150 mm (0.006 in) Lift
• Intake Opens 0.3 degrees ATDC
• Intake Centerline 122.0 degrees ATDC
• Intake Closes 246.0 degrees ATDC
• Exhaust Opens 229.3 degrees BTDC
• Exhaust Centerline 110.0 degrees BTDC
• Exhaust Closes 11.2 degrees ATDC

Submariner409
11-11-07, 06:02 PM
:thumbsup: AJ..........Thanks for the specs. Good reference for the bumpstick loonies.....

Given the intake opening and closing events, the above explains why the 2002 "Y" LD8 engine has sort of an RV midrange torque curve and the "9" L37 is more of a higher RPM tune. ..........and you don't need as much total lift to flow 4 valves instead of 2, and 1.68 is a fairly aggressive follower (rocker) ratio.

AJxtcman
11-11-07, 06:22 PM
I had the 03 cams spec listed different. I am looking for that info.

Cadillacboy
11-12-07, 11:46 AM
Great info ,thanks for that

AJxtcman
11-16-07, 10:05 AM
http://i224.photobucket.com/albums/dd25/AJxtcman/forum/1.jpg

codewize
11-16-07, 10:36 AM
Interesting. The duration is very different, explaining the torque diff of course.

Great info, Points :) Well I tried but it won't let me.

AJxtcman
11-24-07, 03:44 PM
This lead me to believe that 2003 has the best cams. I will dig around to find the other specs. GM has changed them in SI. It shows 00 to 03 all the same.

LD8 ------2000-01--------2002 -------2003 - 05
RH INT--------12572155---------- 12570333---------12565167

LH INT--------12572152---------- 12570332---------12565169

RH EXH ------ 12572154---------- 12570331---------12565165

LH EXH ------ 12572153-----------12570334---------12565166


L37
RH INT--------12572159-----------12570335 ---------12568828

LH INT--------12572156-----------12570336 ---------12565170

RH EXH-------12572158-----------12570337 ---------12568826

LH EXH-------12572157-----------12570338 ---------12568827

The 2002 Cams are the ones listed in the TSB for 2000 and 2001:histeric:

codewize
11-25-07, 11:03 PM
So you're telling me that since my 01 was produced after the cam issue with engine code KBB, that my cams are the same as an 02?

AJxtcman
01-03-08, 05:00 PM
I am at a loss for words.
I have been checking broadcast codes. :crying2:
I have no clue on what they did. I will post a list later. I am confused on my findings.

nigelb
01-03-08, 05:39 PM
so does your post about the rough idle mean that my '00 STS should have new cams?
it has the code JLA on the cam cover and is a 10th digit 'Y' car.
of course, who would foot the bill for all this?
the specs in my FSM are the same as listed above.

AJxtcman
01-03-08, 10:37 PM
Instruction sheet for engine replacement

When using LD8 Engine part #88984255 to replace Broadcast code KHA the dealer must get a VCI

When using LD8 Engine Part #88984254 to replace Broadcast code KMA or KPA the dealer must get a VCI

When using L39 engine part #88984253 to replace broadcast code KKA or KLA the dealer must get a VCI

AJxtcman
01-03-08, 10:48 PM
We know that they used KMA, KKA, KCA, and KBA in 01

I need to do a lot more searching, but this is odd

LD8 VIN (Y)
00 ---
01 KMB
02 JMA runs from 7/01 to 6/02
03 KMA starting in 6/02. They ran this in 01 hmmmm
03 KMB started in 5/03. They ran this in 01

L37
00 ---
01 ---
02 JLA 3/01
02 JKA 7/01 to 6/02
03 KKA 6/02 to ??
03 KKb 5/03 to ??

I have not finished my list, but WTF

I did not look at eldo's yet

AJxtcman
01-03-08, 10:53 PM
ranger I will figure this out, but I am not sure if they had old engines sitting around that they swapped cams in. Oh wait they don't do that they would just scrap them. Hmmmmmmmmmmmm:annoyed:

darien99
01-04-08, 10:40 AM
This lead me to believe that 2003 has the best cams.
Best as in smoothness?
From my little cam reading knowledge it looks like the '93-'95 has the best cams for power. :hmm:

AJxtcman
01-04-08, 02:24 PM
Best as in smoothness?
From my little cam reading knowledge it looks like the '93-'95 has the best cams for power. :hmm:

For 00+

AJxtcman
02-09-08, 06:57 PM
This is a nice tool to hold the cam sprockets in place on 00 to 03. Some time in 03 they switched the size of the Cam bolts and this tool does not work on them.
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar%20Cam%20Swap/J44213SecondaryDriveTimingChainSpro.gif

This to hold the cam from turning when you tighten the cams.
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar%20Cam%20Swap/J44212CamshaftHoldingtool.gif

AJxtcman
02-18-08, 02:09 PM
Has any one with a 00 or 01 ever had the cams changed?
This would be for the rough idle condition.
I need some information It will help with tuning:eek:

AJxtcman
03-06-08, 11:25 AM
Revised Information
1993 - 1998 Cadillac (LD8 (VIN Y )
Valve Timing (With Ramp at 0.100 mm Lift)
Intake Opens 9 BTDC
Intake Closes 55 ABDC
Intake Lobe Centerline 113 ATDC

Exhaust Opens 51 BBDC
Exhaust Closes 13 ATDC
Exhaust Lobe Centerline 109 BTDC

Valve Lift
Intake 8.6 mm 0.339 in
Exhaust 8.6 mm 0.339 in

Duration (@ 0.100 mm Lift)
Intake 244
Exhaust 244

Valve Overlap (@ 0.100 mm Lift) 22

.

1993 - 1999 Cadillac (L37 (VIN 9)
Valve Timing (With Ramp at 0.100 mm Lift)
Intake Opens 13 BTDC
Intake Closes 73 ABDC
Intake Lobe Centerline 120 ADTC

Exhaust Opens 51 BBDC
Exhaust Closes 13 ATDC
Exhaust Lobe Centerline 109 BTDC

Valve Lift
Intake 9.4 mm 0.370 in
Exhaust 8.6 mm 0.339 in

Duration (@ 0.100 mm Lift)
Intake 266
Exhaust 244

Valve Overlap (@ 0.100 mm Lift) 26

.

1999 Cadillac (LD8 (VIN Y )
Valve Timing (With Ramp at 0.100 mm Lift)
Intake Opens 8 BTDC
Intake Closes 55 ABDC
Intake Lobe Centerline 113.5 ATDC

Exhaust Opens 51 BBDC
Exhaust Closes 13 ATDC
Exhaust Lobe Centerline 109 BTDC

Valve Lift Intake 8.6 mm 0.339 in
Exhaust 8.6 mm 0.339 in

Duration (@ 0.100 mm Lift)
Intake 243
Exhaust 244

Valve Overlap (@ 0.100 mm Lift) 21.5

.

AJxtcman
03-06-08, 02:05 PM
If I install the Intake cams on the exhaust side I should get what is listed below.
I will need to cut the end off the left intake cam.
My question is what should I degree it to. The Lobe Centerline or the Opening position?
1993 - 1999 Cadillac (L37 (VIN 9)
Valve Timing (With Ramp at 0.100 mm Lift)
Intake Opens 13 BTDC
Intake Closes 73 ABDC
Intake Lobe Centerline 120 ADTC

Exhaust Opens 61 BBDC ????
Exhaust Closes 23 ATDC
Exhaust Lobe Centerline 109 BTDC ????

Valve Lift
Intake 9.4 mm 0.370 in
Exhaust 9.4 mm 0.370 in

Duration (@ 0.100 mm Lift)
Intake 266
Exhaust 266

Valve Overlap (@ 0.100 mm Lift) 36?????

AJxtcman
03-06-08, 05:03 PM
Revised Specs
2000 - 2003 Cadillac (LD8) 1.68 Rockers
Camshaft Lobe Duration @ 0.006 in Lift - Exhaust 236
Camshaft Lobe Duration @ 0.006 in Lift - Intake 242

Camshaft Lobe Lift - Exhaust 0.2339 in
Camshaft Lobe Lift - Intake 0.2421 in

Camshaft Lobe Overlap @ 0.006 in Lift 19.4 GM has it listed @1.98

Camshaft Timing @ 0.006 in Lift
Intake Opens 5.6 BTDC
Intake Centerline 113.0 ATDC
Intake Closes 236.8 ATDC

Exhaust Opens 222.5 BTDC
Exhaust Centerline 107.0 BTDC
Exhaust Closes 13.8 ATDC

.

2000 - 2003 Cadillac (L37) 1.68 Rockers
Camshaft Lobe Duration @ 0.006 Lift - Exhaust 246
Camshaft Lobe Duration @ 0.006 in Lift - Intake 251

Camshaft Lobe Lift - Exhaust 0.2339 in
Camshaft Lobe Lift - Intake 0.2421 in

Camshaft Lobe Overlap @ 0.006 in Lift 20.5 GM has it listed @ 2.04

Camshaft Timing @ 0.006 in Lift
Intake Opens 0.0 ATDC
Intake Centerline 122.0 ATDC
Intake Closes 251.0 ATDC

Exhaust Opens 225.5 BTDC
Exhaust Centerline 106.0 BTDC
Exhaust Closes 20.5 ATDC
.


2004 - 2008 Cadillac (LD8) 1.68 Rockers
Camshaft Lobe Duration @ 0.006 in Lift - Exhaust 236
Camshaft Lobe Duration @ 0.006 in Lift - Intake 242

Camshaft Lobe Lift - Exhaust 0.2339 in
Camshaft Lobe Lift - Intake 0.2421 in

Camshaft Lobe Overlap @ 0.006 in Lift 6.4 GM has it listed @ 1.98

Camshaft Timing @ 0.006 in Lift
Intake Opens 1.3 BTDC
Intake Centerline 117.0 ATDC
Intake Closes 237.9 ATDC

Exhaust Opens 226.1 BTDC
Exhaust Centerline 111.0 BTDC
Exhaust Closes 5.1 ATDC

.

2004 - 2008 Cadillac (L37) 1.68 Rockers
Camshaft Lobe Duration @ 0.006 in Lift - Exhaust 246
Camshaft Lobe Duration @ 0.006 in Lift - Intake 251

Camshaft Lobe Lift - Exhaust 0.2339 in
Camshaft Lobe Lift - Intake 0.2421 in

Camshaft Lobe Overlap @ 0.006 in Lift 10.9 GM has it listed @ 2.04

Camshaft Timing @ 0.006 in Lift
Intake Opens 0.3 ATDC
Intake Centerline 122.0 ATDC
Intake Closes 246.0 ATDC

Exhaust Opens 229.3 BTDC
Exhaust Centerline 110.0 BTDC
Exhaust Closes 11.2 ATDC

AJxtcman
03-07-08, 04:32 PM
Question for any one that feels up to it!

When building a performance engine do you have more lift and duration on the intake side or the exhaust?:suspense:

Take a look at the specs listed :eek:

fubar569
03-08-08, 01:24 AM
Question for any one that feels up to it!

When building a performance engine do you have more lift and duration on the intake side or the exhaust?:suspense:

Take a look at the specs listed :eek:

depends on application, compression, flow, forced induction, etc...

too many variables to answer your question effectively...

FWIW, i believe the Turbo DSM cars have more duration on the intake side than exhaust because of the particular application (turbocharger)...the difference was quite a bit if i recall. when i did the rebuild i went to something that had a higher intake lift but same duration both sides (crower 413 grind cams) - this made the car a totally different monster! a bit more below 3k but once the turbo spooled and the cams came into power it was like ZOMGWTFBBQ!!!!!

AJxtcman
03-14-08, 03:14 PM
edit out

AJxtcman
04-08-08, 04:18 PM
Cam timing ?

AJxtcman
04-08-08, 07:12 PM
I need some input on this
This is a slopping Northstar Crank and Crank gear! They are all this way!

Crank pin. It is a roll pin
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar%20Cam%20Swap/Crankpin.jpg

The gear all the way to the left. This is not clean and has some oil on it
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar%20Cam%20Swap/HPIM0206.jpg

This is in the middle range
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar%20Cam%20Swap/HPIM0207.jpg

This is all the way to the right. you can see the oil
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar%20Cam%20Swap/HPIM0208.jpg

UhiWjLyeZKI

dkozloski
04-08-08, 07:44 PM
I assume you are interested about the slop in the timing pin. What I see there is not remarkable. We used to play around with offset keys on Chevies. Advancing the cam timing improves the bottom end and retarding the cam timing improves the top end. A typical adjustment would be nearly 1/2 the width of the key. With the slop I see there I don't think you could measure the difference in performance.

Ordinarily, playing around with cams and valve timing is like wiping your ass with a hoop. There is no end to it.

AJxtcman
04-08-08, 07:46 PM
I assume you are interested about the slop in the timing pin. What I see there is not remarkable. We used to play around with offset keys on Chevies. Advancing the cam timing improves the bottom end and retarding the cam timing improves the top end. A typical adjustment would be nearly 1/2 the width of the key. With the slop I see there I don't think you could measure the difference in performance.

Ordinarily, playing around with cams and valve timing is like wiping your ass with a hoop. There is no end to it.

Great I like to hear that. I was wondering. I was not sure. Thanks for the input:thumbsup:

Submariner409
04-08-08, 09:38 PM
What dkoz said:

Loosely, advancing the cam 4 degrees in a single cam OHV engine will move the power/torque band somewhat lower in the rpm range. retarding the cam the same amount will move the power band higher in the rpm range. (Take a look at any popular aftermarket cam drive setup and you'll see 3 keyways milled into the crank gear. Advance, straight up, and retard. Now figure out where you want your new engine to run most of the time................)

Very simplistic, and doesn't take into account all the changes which can be accomplished with different cam ramp speeds, roller ramps, valve overlaps, lobe center juggling, and overall lift ratios. Not to mention the infinite variations in tuning afforded by a DOHC chain drive setup: you mess with one cam, it changes the other's characteristics without touching it. TANSTAAFL (there ain't no such thing as a free lunch)

AJxtcman
04-08-08, 10:58 PM
The oil pump is in between the balancer and the gear. when we tighten them the crank is in a clockwise motion. When I did Highline Cady's engine I turned the crank counterclockwise as I installed and tightened the balancer. This was the only thing I changed in my assembly procedure. The car does not sound the same. I said it was the converter, but I wasn't sure. I didn't think that the small change was that much. Maybe 1 or 2 . Like I said I wasn't sure about this.:D

AJxtcman
04-08-08, 10:58 PM
Thanks guy's :thumbsup:

dkozloski
04-09-08, 12:36 AM
Back in the day there were several gear drive setups available for small block Chevies that allowed you to adjust cam timing without disassembling the engine. There was even one that advanced the cam timing on the fly with hydraulics like a VVT 3.6L. I invented one myself where I drove the cam with helical gears so all I had to do to adjust cam timing was the slide the cam back and forth in the block. I drove the distributor with helical gears with the opposite pitch so as the cam slid back and forth ignition timing stayed the same. I never got the actuator to be repeatable so I gave up on it.

AJxtcman
08-26-08, 07:24 AM
Wheel to Wheel Inc Cam Specs
INTAKE
DURATION @ .006" 267
DURATION @ .050" 224
LOBE LIFT .4000"

EXHAUST
DURATION @ .006" 255
DURATION @ .050" 212
LOBE LIFT .3700"

More spec to come

AJxtcman
09-03-08, 02:06 PM
Wheel to Wheel Inc Cam Specs
INTAKE
DURATION @ .006" 267
DURATION @ .050" 224
LOBE LIFT .4000"

EXHAUST
DURATION @ .006" 255
DURATION @ .050" 212
LOBE LIFT .3700"

More spec to come


I just got my cam in today. They were ground for Wheel To Wheel.
They are for a 99 and prior engine.

AJxtcman
10-26-08, 11:10 AM
http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/83.jpg

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/82.jpg

Submariner409
10-26-08, 12:27 PM
The lobe timing specs for .050" lift on both cams (212 and 224 degrees) are right in the ballpark for a RV/mild street grind from any cam manufacturer. Get into the Comp Cams spec sheets and look at their street hydraulic series. The timing spec at .006" lift is the most often quoted in advertising because it looks like the old "270 degree" hype of years ago. More common nowadays is the .050" lift specs which really reflect the cam's operating properties. The lobe lifts give a valve lift of about 0.5" to 0.64", which is perfectly acceptable with a 1.5:1 or 1.6:1 cam follower (OHC version of a rocker arm.).

Advance those cams 4 degrees and the power band starts at around 2,600 rpm and goes to the mid 5,000's. Retard them 4 degrees and the power band moves up to 4,000 to 6,600 or so. No magic. Just standard cam timing and tuning. Been like that for 70 years of cam grinding. Exactly why Cloyes and others machine 3 timing keyways into their crank gears: advance, straight up, retard.

212/224 is nothing special........on the low side of mild street. 99% of Cadillac owners would have absolute fits if their engine idled at 900 rpm with a Krass & Bernie "rump, rump, rumpa......"

AJxtcman
10-26-08, 02:55 PM
The lobe timing specs for .050" lift on both cams (212 and 224 degrees) are right in the ballpark for a RV/mild street grind from any cam manufacturer. Get into the Comp Cams spec sheets and look at their street hydraulic series. The timing spec at .006" lift is the most often quoted in advertising because it looks like the old "270 degree" hype of years ago. More common nowadays is the .050" lift specs which really reflect the cam's operating properties. The lobe lifts give a valve lift of about 0.5" to 0.64", which is perfectly acceptable with a 1.5:1 or 1.6:1 cam follower (OHC version of a rocker arm.).

Advance those cams 4 degrees and the power band starts at around 2,600 rpm and goes to the mid 5,000's. Retard them 4 degrees and the power band moves up to 4,000 to 6,600 or so. No magic. Just standard cam timing and tuning. Been like that for 70 years of cam grinding. Exactly why Cloyes and others machine 3 timing keyways into their crank gears: advance, straight up, retard.

212/224 is nothing special........on the low side of mild street. 99% of Cadillac owners would have absolute fits if their engine idled at 900 rpm with a Krass & Bernie "rump, rump, rumpa......"

No rockers on this engine.
Take a close look at the spec. The cams have not the locating pin redrilled. They are in the stock location.

One sheet is for the intake cams the other is for the exhaust cams for the same engine.

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/83.jpg
1993 - 1999 Cadillac (L37 (VIN 9)
• Valve Timing (With Ramp at 0.100 mm Lift)
• Intake Opens 13 BTDC
• Intake Closes 73 ABDC
• Intake Lobe Centerline 120 ADTC

• Exhaust Opens 51 BBDC
• Exhaust Closes 13 ATDC
• Exhaust Lobe Centerline 109 BTDC

• Valve Lift
• Intake 9.4 mm 0.370 in
• Exhaust 8.6 mm 0.339 in

• Duration (@ 0.100 mm Lift)
• Intake 266
• Exhaust 244

• Valve Overlap (@ 0.100 mm Lift) 26

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/82.jpg

97EldoCoupe
10-26-08, 04:16 PM
So the Aurora 4.0 engines are running LD8 cams? I'll have to double check this for the 95-99 4.0 engines. They are already pushing over 1 hp/cubic inch, just as the L37 4.6's are, with LD8 cams? What would happen if you swap L37 cams into the L47 Aurora motor? They have more lift, so the pistons may need a bit of machining to accept the added lift...

L47 4.0 Auroras - 250 HP, 260 FT. LBS. >>>>>>Over 1 HP/c.i.,
BOTH ENGINES HAVE THE SAME CAMS, WHAT GIVES?
LD8 4.6 Cadillacs- 275 HP, 300 FT. LBS. >>>>>>Less than 1 HP/c.i.

Something must have been done right on the L47 Aurora motors to get 250 hp out of 244 cubes, with LD8 cams..... Sounds like a good little engine for tuning....

AJxtcman
10-26-08, 04:26 PM
So the Aurora 4.0 engines are running LD8 cams? I'll have to double check this for the 95-99 4.0 engines. They are already pushing over 1 hp/cubic inch, just as the L37 4.6's are, with LD8 cams? What would happen if you swap L37 cams into the L47 Aurora motor? They have more lift, so the pistons may need a bit of machining to accept the added lift...

L47 4.0 Auroras - 250 HP, 260 FT. LBS. >>>>>>Over 1 HP/c.i.,
BOTH ENGINES HAVE THE SAME CAMS, WHAT GIVES?
LD8 4.6 Cadillacs- 275 HP, 300 FT. LBS. >>>>>>Less than 1 HP/c.i.

Something must have been done right on the L47 Aurora motors to get 250 hp out of 244 cubes, with LD8 cams..... Sounds like a good little engine for tuning....
they did that

Submariner409
10-26-08, 04:31 PM
Post #36.

Repeats exactly what I said: "....1.5 or 1.6 cam follower (OHC version of a rocker arm)" and the pair of cams at 212/224 duration at .050" lift is exactly parallel to a single OHV cam RV/mild street grind.

If you want to get picayune, then the cam follower analogy could read ......."and an OHC cam follower with a lift ratio of 1.5 or 1.6 gives the same valve lift as an OHV rocker arm with a lift ratio of 1.5 or 1.6."

Regardless of the semantics, the pair of Northstar cams described are nothing more than a common V8 mid-rpm moderate torque grind which gives good driveability and a decent idle.

AJxtcman
10-26-08, 04:45 PM
Post #36.

Repeats exactly what I said: "....1.5 or 1.6 cam follower (OHC version of a rocker arm)" and the pair of cams at 212/224 duration at .050" lift is exactly parallel to a single OHV cam RV/mild street grind.

If you want to get picayune, then the cam follower analogy could read ......."and an OHC cam follower with a lift ratio of 1.5 or 1.6 gives the same valve lift as an OHV rocker arm with a lift ratio of 1.5 or 1.6."

Regardless of the semantics, the pair of Northstar cams described are nothing more than a common V8 mid-rpm moderate torque grind which gives good driveability and a decent idle.

My bad
This engine has the cam placed over the valve. The lifter sits in between them.

Look at the intake specs on the exhaust sheet and the Exhaust specs on the intake sheet. Also the Lobe Center-line is confusing

Submariner409
10-26-08, 04:47 PM
Wrong. The cam is offset and the follower has a 1.6 lift ratio. The hydraulic lash adjuster is static and gets its oil pressure from the D-shaped gallery on the inboard side of the adjuster. All the lash adjuster does is to preload the valve train: it serves no lift function.

SOME OHC engines use a direct-acting valve setup with hardened caps on each valve tip; the caps come in various thicknesses to allow valve lash mechanical adjustments, while newer engines, such as the Northstar, use a lash adjuster to keep the valve train quiet. (Wouldn't want "tickety-tick" in your Cadillac, would you ??

AJxtcman
10-26-08, 04:51 PM
Wrong. The cam is offset and the follower has a 1.6 lift ratio.

Not on 93 to 99 Engines
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar/Northstarlifter11.jpg

00+ Roller Engine
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar/HPIM3829.jpg

93 to 99
http://i224.photobucket.com/albums/dd25/AJxtcman/Northstar/HPIM3830.jpg

Submariner409
10-26-08, 05:09 PM
:eek: CAUGHT in the '99+ engine redesign !!! Sorry....

So in your cams, the lobe lift is also valve lift because there is no mechanical multiplication available from an offset cam follower.

That explains the moderate valve opening available: .370"/.400"

Theoretically, you should be able to twist a pre-2000 engine a bit faster because there's less stuff between the cam and valve tip.

AJxtcman
10-26-08, 05:13 PM
:eek: CAUGHT in the '99+ engine redesign !!! Sorry....

So in your cams, the lobe lift is also valve lift because there is no mechanical multiplication available from an offset cam follower.

That explains the moderate valve opening available: .370"/.400"

Theoretically, you should be able to twist a pre-2000 engine a bit faster because there's less stuff between the cam and valve tip.

I think the roller helps more than it loses. The older motors scrub the lifters as you can see in the pictures.

97EldoCoupe
10-26-08, 09:41 PM
:DJust for laughs, install the cams from a '93-'99 L37 into a 2000+ engine, so the rockers multiply the lift from the older, more agressive cams.... LOL J/K

AJxtcman
03-28-10, 02:39 PM
Comp Cams has Northstar Cams for the guys that didn't know that
I should pull out my sheets and get all 3 part numbers.

Left Intake -- Right Intake -- Exhaust Cams (both are the same)

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=99-999-3&Category_Code=

http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=99-999-1&Category_Code=

AJxtcman
03-28-10, 02:53 PM
The Comp cams are figured at .006" lift and the stock cams are figured at .0039" lift

Does anyone know at what lift CHRF spec are figured at. I have asked Alan in the past, but I didn't get an answer

From Alan
The 272 cams specs are:
INTAKE
lift = .396"
open = 33 BTDC
close = 35 ABDC

EXHAUST
lift = .396"
open = 43 BBDC
close = 1 BTDC


One sheet is for the intake cams the other is for the exhaust cams for the same engine.

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/83.jpg
1993 - 1999 Cadillac (L37 (VIN 9)
• Valve Timing (@ 0.100 mm or .0039" Lift)
• Intake Opens 13 BTDC
• Intake Closes 73 ABDC
• Intake Lobe Centerline 120 ADTC

• Exhaust Opens 51 BBDC
• Exhaust Closes 13 ATDC
• Exhaust Lobe Centerline 109 BTDC

• Valve Lift
• Intake 9.4 mm 0.370 in
• Exhaust 8.6 mm 0.339 in

• Duration (@ 0.100 mm or .0039" Lift)
• Intake 266
• Exhaust 244

• Valve Overlap (@ 0.100 mm or .0039" Lift) 26

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/82.jpg

AJxtcman
03-28-10, 03:04 PM
Sub do those numbers add up to you?

Cheatin' Chad
07-30-10, 02:43 AM
I just got my cam in today. They were ground for Wheel To Wheel.
They are for a 99 and prior engine.

What gains where made with the cam swap?

Submariner409
07-30-10, 12:17 PM
Understand that these cams were ground for a kit car, not a daily driver.......
and the pre-2000 management systems are different, so there are hoops to jump through..........

The intake cam from Alan looks like it's timed at .050" lift, which comes out to 248 degrees, just about right for a cam advertised as being a "270 degree cam" - if that quote was based on a measurement at .005" lift. It's advertising gamesmanship which is why most cam grinders now give the figures for .050". The other grinds bounce all over the place with a couple being 266 at .050" which is quite radical for a street cam, and you would need a stand-alone management system because a PCM or ECM could never self-adjust to that grind. Gotta be careful with valve springs, too - flat-tappet followers won't take a lot of spring pressure with the crummy oils we now get.

AJ, Sorry I'm 4 months late on this one.......

AJxtcman
07-30-10, 12:24 PM
What gains where made with the cam swap?

They are still sitting in the boxes.
I think lifters are $35 each X 16 = $560

Now the engine I have only had 3300 miles when I put it in my car. The Lifter were already going out on the engine. No Zinc anymore :eek:

Submariner409
07-30-10, 12:43 PM
Hi...........

Rotella or LongLife 10W30 or 10W-40 ???

AJxtcman
02-07-11, 09:22 PM
http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/83.jpg

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/82.jpg

I would like to sell these cams
http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/CompCams/CompCams2.jpg

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/CompCams/CompCamS1.jpg

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/CompCams/CompCams3.jpg

As you can see they are CompCams that were ground for a customer called Wheel To Wheel inc
They are the company that did Tool Time Tim Allens DTS

AJxtcman
02-08-11, 11:58 AM
...........a picture of the CompCams Northstar cams and the NIB CompCams box with ID.

I can't find the darn things anywhere, and CompCams and Google can't seem to come up with any help, either.

EDIT: Hah !! You already answered this over in the old "Northstar Cam Specs" thread. (We're back to last summer again................) Read the whole thread, troops - these cams are regrinds for something other than a PCM-controlled FWD Northstar daily driver VIN 9 or VIN Y pre-2000 engine.

EDIT # 2: The CompCams P/N 99-999-3 is a generic "Engine parts" number - looks like all sorts of stock and special work falls into this particular number. Look at the .050" lift specs for those two cams and you'll see that they're a fairly mild "street" regrind. Running durations of 212* and 224* are common. The high torque/low rpm cams I use in my Olds 455 engines for boats come in at durations (at .050") of 204 and 214 - just about 10 degrees less than these Comp units. It would be interesting to compare the posted total lobe lifts with the OEM Northstar lifts.

I talked to Sub a few months back about these cams. It looks like they are just a little bigger than stock OE, but the cam card specs are all messed up and they include the Exh spec on the Intake card and vice versa.

I have the CompCams boxes that they came in. Hmmmmm Maybe I will fire up the Fiero and pull it out of the way to get to the boxes. Maybe I will take a picture or 2

They maybe regrinds, but I have nothing that says they are. I feel that these cams will run just fine in a STS

AJxtcman
02-08-11, 12:46 PM
http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/CompCams/CamsBoxes.jpg

http://i224.photobucket.com/albums/dd25/AJxtcman/93%20to%2099%20Cams/CompCams/CamBoxLables.jpg