Lookup Melling CCS-39. It is your factory cam. The 9C1 cop cars had the L98 TPI cam in them and had 25 HP more than you with the same longblock, manifolds and TBI (bigger injectors only).
Lookup Melling CCS-39. It is your factory cam. The 9C1 cop cars had the L98 TPI cam in them and had 25 HP more than you with the same longblock, manifolds and TBI (bigger injectors only).
Well, okay you have me convinced I have the infamous "peanut" cam. And since that appears to be the case, my prior idea of installing 1.6 rockers to make the cam act a little bigger is completely inadequate. That cam has to go! I found an LT1 on ebay, but it's the smaller one. This one: 1994-1996 B-bodies (including L99 4.3L): 191/196 0.418/0.430 lift 111 LSA. It has specs very similar to the 264 cam I have. I am really thinking the 264 might be a good one to use, especially with 1.6 rockers. Fast355, why do you dislike the 264 vortec cam? It's more or less only slightly smaller than all the LTX cams, and only a 1/2 step down from the renowned 395 cam. With 1.6 rockers it should be more like 194/199 .442/.457... That's not that much smaller than these other ones, plus it's free, probably a little easier to tune, and a vast improvement over the garbage that's in there now. If you really think the 264 is a waste of time I'll wait for a better LT1 cam to come on to ebay, but I don't really understand why you have this animosity towards it.
1990 Cadillac Brougham with all original VIN 7 GM TBI roller 350. 78,000 miles, 3.23 rear, rebuilt and upgraded 700R4 with 1500 stall. Engine upgrades include: Ultimate TBI mods, big air cleaner, SMOG pump/system delete, cat delete, high flow y pipe.
Not a fan of the Vortec cam because the torque curve drops from 2,600 rpm. With the L31 in my Express you could roll on the throttle at 80-85 MPH, catch a downshift to 3rd, engine would rev up to about 4,000rpm and the acceleration would drop off. I put a LT4 cam and 1.6s in it. Lost NOTHING down low and saw gains of close to 40 HP up top near the 5,200 rpm shifts. Same thing with the F-car LT1 cams I put in the L05 in my 83 G20 and the L31 that went into my brothers 99 Suburban with a F-car LT1 cam.Originally Posted by Danoby
Here is the nail in the B-car LT1/Vortec cams coffin for me. It idled rougher and got poorer fuel economy than the F/Y car cams.
Stock Cam/Tuned
http://www.youtube.com/watch?v=vc1lHlBLdkw
LT4 Cam/1.6s/Same Tune/Shorties
http://www.youtube.com/watch?v=7SgptElOCpY
Hmm. Do you think some of the added power came from the shorties and 1.6 rockers? I mean you went from 191/196 .418/.430 111 LSA to 196/206 .431/.451 109 LSA which is not that big of a difference, but also added 1.6 rockers for .460/.481 plus the headers. The biggest difference it looks like to me is the added lift, most of which is attributed to the 1.6 rockers, plus the shorty headers. I am not saying the 395 isn't a better performer than the 264 as it certainly is, but I think the difference is marginal compared to the difference the 1.6's and headers provide. You actually have vortec heads on that van, too. I am still working with the swirl ports...
In any case, I think I need to learn to tune this thing. It would probably benefit dramatically from a tune right now with the air cleaner, TBI mods, high flow y pipe and cat delete, etc... Maybe I should get acquainted with the process now before I swap in the cam and have more severe changes to deal with? I would hate to swap in a better cam - almost any cam is better than the one I have - and have performance and idle quality problems. That would suck.
1990 Cadillac Brougham with all original VIN 7 GM TBI roller 350. 78,000 miles, 3.23 rear, rebuilt and upgraded 700R4 with 1500 stall. Engine upgrades include: Ultimate TBI mods, big air cleaner, SMOG pump/system delete, cat delete, high flow y pipe.
I have played musical cams with the Express.
1.) 264 was the stock cam
2.) 142 LT4 cam w/1.6s 203/210 @ .050 on a 115
3.) Comp 4x4 206/210 @ .050 on a 110
4.) Comp Custom 215/220 @ .050 on a 114 (On Etec170s)
5.) 395 Marine cam w 1.6s (May go with 1.7s soon)
The Marine cam has more aggressive lobes, 5° more intake duration, 10° more exhaust with less .06" duration, 2° tighter LSA which makes it noticeably more powerful. It also has .017" more intake lift and .023" more exhaust lift. When you put 1.6s as opposed to the stock 1.42s on the Marine cam it is really close to a LT1 cam with 1.42 rockers except its cut on a tighter LSA. It specs about 200/210 @ .050, .451/.481" lift, 109 LSA. It has a slightly noticeable idle but it pulls hard from off-idle through 5,000 rpm.
My old G20 van had an 8.75:1 TBI 350 with 350 heads in it. Used the 142' LT4 cam in it back in the day. Very nice running and driving setup even with the stock 1,600 rpm converter in the 700r4 and 3.08 gears.
There is another guy that tested a Vortec cam vs 1995 F-car LT1 cam in his 1996 K1500. Back to Back testing even untuned showed a gain starting at 4,000 rpm and a peak gain of 13.5 HP at the tires at 5,100 rpm. Lost NOTHING from the start of the test to redline.
Last edited by Fast355; 11-15-2015 at 07:05 PM.
You are correct though. You do need to learn how to tune as well as check your engine over carefully and get it ready for more mods. Adjustable fuel pressure regulator, Stronger fuel pump, tuneup stuff good, compression checked, etc. I would also recomeend that you check to make sure you don't have the 048 ignition control module and have either a 369 or a DUI Dynafire module. The 048 module retards the timing over 3,500 and makes the engine gutless above that.
Okay, you have me convinced I need at least an LT1 cam or better yet the 395 cam. But, maybe I need to look into the tuning stuff first. I already have an adjustable regulator set to about 12 psi and a TPI fuel pump. Does the ignition module retard spark advance based on feedback from the knock sensor?? The tune up stuff is all done as well - new plugs, wires, cap rotor, distributor. It has a new knock sensor, new EGR valve. Basically, this thing is ready to go except for the valve stem seals, which will get replaced with the cam and 1.6 rockers install, and perhaps the ignition module you mentioned. How can I identify the module that I have? How do I get started with tuning?
1990 Cadillac Brougham with all original VIN 7 GM TBI roller 350. 78,000 miles, 3.23 rear, rebuilt and upgraded 700R4 with 1500 stall. Engine upgrades include: Ultimate TBI mods, big air cleaner, SMOG pump/system delete, cat delete, high flow y pipe.
This was a stock vortec with only a cam change and a slight bit of exhaust rework prior to the dynos.
I played with a TBIs years ago.
This engine was rated at 190 HP/300TQ at the flywheel and only had headers, exhaust, edelbrock 3704, TBI mods, and Tuning.
Open center TBI spacer, open element, hypertech powerbowl, and 1.6 rockers.
Then I dropped a 454 TB on it with high pressure injectors, LT4 cam, left the 1.6s, and ran it.
For a modest low cost, for modest performance gains
dave w
All due respect Dave, those cams don't even work as well as the stock 201/208 LT1 cams in the 350s. I ran a LT1 cam on a STOCK 299' AWLD calibration for months with nothing more than 14 psi of fuel pressure, 6° BTDC on the timing, and a slight tweak of the minimum air rate screw on the throttle body. It was smooth, made good torque, had a great idle, and gave great fuel economy. Idle was a bit rich with the BLMs in the 110 range but otherwise worked very well. Minimal tuning would have fixed the VE tables and the advance curve could have been quicker with more initial timing to give even more low-end power.For a modest low cost
dave w
Last edited by Fast355; 11-15-2015 at 07:37 PM.
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