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Cam options for the 3.4 DOHC are few and far between. You could possibly have Crower or some other company make a solid billet cam set custom for your motor, but thats going to cost anywhere from $1000-2000. The alternative is to have the stock cams reground for a better profile. Lunati will NOT do them, same goes for Crane. A company in California will do them however for around $500. You can contact them on thier website, Cadillac Hotrod Fabricators.
UPDATE 6-8-05
I haven't verified this but a member on the forum has noted that Crower will do the regrinds for 400.
UPDATE: 6-29-07
Fieromadman has found another source for cam regrinds. Has done three sets of DOHC cams that worked excellent. Looking at around 100 a cam.
Steve Long Racing Cams INC. 951-273-0816
(Read a recent thread about cam regrinds)
Cam Timing
Because the cam gears are not keyed, the options for cam timing are nearly infinite. While this can cause a problem for the novice trying to set the cam timing, it also allows great flexibility for those with more experience. First, I must add that any painted timing marks are to be ignored. To learn more about how to set the cam timing, go here.
It has been over a year now that the 13 degree exhaust retard spread across the internet as an easy way to get power out of this motor. It seems that another person has experimented with the timing on a ported engine mated to the automatic trans. It retains the 13 degree aspect but advances the intake cam as well to lower the powerband from what we had already tried. I hope this is right, 7 degrees advanced on the intake, 6 degrees retarded on the exhaust. As of now I do not know where this lines up the timing mark for 91-93, so you are on your own for figuring it out. I do however have a better picture to show the timing mark for the 10 and 13 degree timing. Basically, 10 degrees is what I thought 13 was originally. I am now running 13 on my car but the idle is a hair rougher than with 10.
Stock Timing

10 Degree Retard

13 Degree Retard
Update: 6-8-05 I have now tried 6 advance intake / 6 retard exhaust on a 94 cutlass and my 91 grand prix. The cutlass is an automatic, and was timed to stock from the belt stretch timing of -8/-8 rear bank, -4/-2 front bank. This obviously made the car idle and run better than before. The 6/6 timing was then applied. Wow...simply amazing for an automatic. The powerband starts lower, idle is smoother than stock timing, and low end is increased a nice amount. Top end was helped out as well over stock though with the auto, stock shift points don't go as high as you can with the manual. The owner also noted an increase in gas milage though I also tuned the chip with this timing done. I am testing the gas milage in my car now.
6/6 timing on a manual car is a different animal, because instead of shifting at 6200, I usually went to 6600 or so (power dropped after 6600 with 13 degree retard on my motor). My car now only likes to make power to 6200 or so and then drops off noticably. The low end is a hell of a lot nicer and the exhaust note when I cruise around at 1500 is smoother. It no longer feels like its working hard below 2500 I am going to try some more settings out later after I tune my car how it sits and compare gas milage.
If you are wondering how I am able to accurately set the cam timing to 6/6, check out this product on our store. DOHC Timing Tool. I highly recommend this tool as it has made my life easier on all the cam settings I want to try out.
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Anyway - other cam timing considerations:
First off: The 95 and up motors had the infinite adjustability by just loosening the bolts on the cam sprocket & giving it a tap. In pre '95 motors you needed to swap out the sprockets & keepers for the later models to achieve this. As far as I know there were no pre 95 motors with the easily adjustable cam sprockets.
Next: On the pre - 95 motors it is possible to time the cams 180 degrees out (learned this the hard way). This is because the computer takes the cam sense signal from the "dummy" INTERNAL cam - which really serves no other purpose on this motor other than as a drive pulley for the cam belt. In the 95+ motors there was a cam sensor on the intake cam for the #4 bank that did this, so there was no possibility of timing 180 degrees out - it read the actual position of the overhead cams, not the internal "dummy". In the pre 95' motors the paint marks on the "internal cam pulley" must be UP when the motor is at TDC to time the #1 bank. If it's DOWN then start by timing the #4 bank first. The motor doesn't really time to the #4 bank (as has been stated on a couple of threads), unless the internal cam is in the "180 out" position. You have to remember that this internal cam only rotates once for every TWO rotations of the crank - and since it feeds the computer - yes, kids, there IS a "180 degrees out" setting (been there, done that).
Anyway - just thought I would pass that hard-earned knowledge along.....
Dana.
94-97 have the easy to adjust cams. 91-93 use a press fit setup which means a puller is needed. All are fully adjustable though (non keyed).
Your cam timing has to be mod specific, as retarding both cams on a stock intake/exhaust motor doesn't work too well at all. It does show that the motor is setup to easily adjust to other mods though.
As far as being 180 out, that is not true. The dummy cam has no sensor. 91-93 is batch fire so it doesn't need to know which bank is which. THe only 180 out timing is if you set both banks with the cam flats up, leaving you with a dual inline 3 cylinder basically. Both banks will be on the compression stroke at the same time. The original manual failed to express the need to time 1 bank, then turn the crank 360 degrees to time the other bank.
SO ...... how does the motor know when to fire #1 vs. #4. Several folks have said via the crank sensor ..... except the crank is going to be in the same position when #1 fires as when #4 fires (just one crank rotation later).
That's what's making me crazy. How does the car know when to fire #1 vs. #4. It can't be firing both at once, otherwise it would have run before I swapped the wires.....
Confusion reins, my head hurts.....
Dana.
1. When I timed the cams I DID get one intake a bit out - about 4 degrees retarded from where I wanted it (I actually timed the cams to some custom numbers, not "stock" settings).
2. Discovered that the majority of the problem was due to a BRAND NEW set of ACCEL 8 mm wires. The reason moving the wires made a difference was simply because I disconnected / reconnected the wires. I found rubber "flaps" inside some of the boots that were preventing good contact on the distributor ends. Tested the wires, resistance was all over the charts wire to wire.
3. Retimed the cams, corrected the 4 degree error I had made on the one cam, installed Taylor Made wires, car started, ran like a banshee.
Took 2nd in an EMRA TT at the new Lightning Raceway at New Jersey Motorsports Park (ST3). Car was easily capable of taking first (I wasn't that day, unfortunately - missed it by 0.1). In the closing laps of practice I snapped yet another BRAND NEW part - a Timken rear hub assembly. Happened to have a stock bearing / hub assembly backup, swapped out the assembly, but I was a bit hesitant after losing the left rear wheel just a few laps earlier (according to my hot lap timer I slowed by over 2 seconds a lap).
Anyway - thanks for all the help when I was trying to determine what the heck I did wrong. I felt much better when I discovered the real culprit was parts more than anything I did wrong. Well, both the bad parts AND lack of knowledge have been taken care of now......
Thanks, all. On to Pocono Raceway (East Course) on August 12 (EMRA again), Then CART (Connecticut Autocross and Rally Team) on August 29th (Pocono North), EMRA August 31 (Pocono North again!).
If anyone is interested in running any time trials in the Northeast let me know - I'll can give you the details for any given course / event. September 29th - CART is running at Pocono - ALL 3 COURSES AT ONCE ALL DAY, 75 car MAX (max of 25 cars per race course). Two time trials, unlimited track time (no "run groups") across 3 different circuits (this one is almost full - $240 for the day).
Dana.