7.4L Cam shaft options

[cool_as_crap]

I didn't know FSC kicked the bucket, must be recent. That cam above is damn near identical to mine, 212/218 .518"/.527" 114+2. Drives like stock with no VE or MAF changes. Mine has a little valvetrain noise, how about yours crap? I did install the Comp adjustable valvetrain sleeves and studs. Really should get around to measuring and swapping in the correct length pushrods.

I haven't noticed any noise changes, my hearing is pretty damn awful though

 

[Supercharged111]

Supercharged111, how did that cam do compared to a stock cam, any economy improvements, noticeable power increase?

I really didn't drive it with the stock cam that much so can't say. All I had really done were a few rips around the block before I swapped the cam out. I will say the powerband feels stock and, other than a little valvetrain chatter which may only be uncorrected geometry, it is a very smooth driving and friendly cam. I get 10.5 mpg empty and the only time I checked loaded was 5.5 with the 5k slide in and 8-9k trailer behind. Held OD at lower elevations surprisingly well.

 

[cool_as_crap]

I finally got an accurate mpg, since my tires are larger than stock my trip was always off.
Using google maps from 1 gas station to the next, all freeway, a/c on, tonneau cover, and driving 80, i got 12mpg. I was pretty shocked since its still factory tuned.
The only mod is that cam.

 

[Christian Steffen]

I finally got an accurate mpg, since my tires are larger than stock my trip was always off.
Using google maps from 1 gas station to the next, all freeway, a/c on, tonneau cover, and driving 80, i got 12mpg. I was pretty shocked since its still factory tuned.
The only mod is that cam.

That's pretty good for a dually at 80, especially on the stock tune, granted I don't have a dually to compare this with.

 

[rpoL98]

It's a bummer FSC is gone, there was a lot of info on our stock cam and upgrades on that forum, plus a massive 7.4 vortec generic thread.

http://www.fullsizechevy.com/forum/...al-maintenance/177272-96-99-454-vortec-owners

I think they're still around??? as of today (Nov 5th, 2018).

 

[William Wiggins]

Just did a cam swap in my '97. The cam you posted is close on duration. It's a little lower on lift and the lobe separation needs to be lower if you actually want it for towing. 108 is as low as comp can go with their cores.
Finding info on these trucks is deff harder than the newer LS stuff I play with daily.

 

[Schurkey]

I have been kicking around the possibility of doing a cam swap in m 97 7.4L.

1. That'll have a roller cam/lifters with a thrust plate. Wonderful set-up. I converted my boat Mark IV 454 to the Gen 6 thrust plate system. Requires a different timing set than the non-roller-cam engines. Of course, you've already got that stuff.
2. The Vortec heads will have valve rotators under the valve springs. You probably don't want to install stiff valve springs on the rotators. You'll need 16 valve rotator eliminator shims. There are two styles I'm aware of--one part number for regular valve springs, one part number for beehive springs. The shims came in 8-packs when I bought mine, so I needed two sets.
3. The INTAKE valve guide bosses have a small radius where the valve spring pockets are cut. This radius can interfere with the rotator eliminator shims. Be sure the shims fit flush on the valve pocket, and grind clearance in the radius if needed. I had to touch-up two intake guide bosses on each head. The other two cleared without rework.
4. I converted the valve train to an adjustable style. Not absolutely required, but kinda nice. Various vendors sell the "special" rocker studs for a screw-in system, no machining needed.
5. Buddy of mine has a Vortec K2500. One of the best upgrades he says he's ever done was to scrap the original muffler. VERY restrictive. He's since added headers and custom-bent exhaust, but the muffler change made a big difference by itself.

 

[cheerdude63]

5. Buddy of mine has a Vortec K2500. One of the best upgrades he says he's ever done was to scrap the original muffler. VERY restrictive. He's since added headers and custom-bent exhaust, but the muffler change made a big difference by itself.[/QUOTE]

I have actually just purchased a Magnaflow performance muffler and having a guy bend me a 3 inch dual out pipes. Should be awesome! I have a series of hills to pull something up. I am thinking I will document the performance and economy after every upgrade. Starting with the Exhaust, then intake tube set up, then ECM swap, then cam. Should be cool to see what everything does.

 

[BNielsen]

5. Buddy of mine has a Vortec K2500. One of the best upgrades he says he's ever done was to scrap the original muffler. VERY restrictive. He's since added headers and custom-bent exhaust, but the muffler change made a big difference by itself.

I have actually just purchased a Magnaflow performance muffler and having a guy bend me a 3 inch dual out pipes. Should be awesome! I have a series of hills to pull something up. I am thinking I will document the performance and economy after every upgrade. Starting with the Exhaust, then intake tube set up, then ECM swap, then cam. Should be cool to see what everything does.[/QUOTE]

How did you have the pipes ran? I'm looking at running 3" dual tailpipes and I haven't seen anyone run that size and retain the spare tire.

 

[Christian Steffen]

5. Buddy of mine has a Vortec K2500. One of the best upgrades he says he's ever done was to scrap the original muffler. VERY restrictive. He's since added headers and custom-bent exhaust, but the muffler change made a big difference by itself.

I have actually just purchased a Magnaflow performance muffler and having a guy bend me a 3 inch dual out pipes. Should be awesome! I have a series of hills to pull something up. I am thinking I will document the performance and economy after every upgrade. Starting with the Exhaust, then intake tube set up, then ECM swap, then cam. Should be cool to see what everything does.[/QUOTE]

Please do. All too often the differences aren't well documented. I know I'm guilty of not documenting before and afters.