Be sure you look very closely at the pushrod when the leading edge of the rocker is in the full down and up position. On both of the motors I did 1.6 ratio self aligning rockers on I had to drill out the rocker hole in the head so there was adequate clearance between the head and the push rod. Both times the push rods were rubbing the heads. This was also on the 96 up vortec style 350 like you have so it's very probable you will have to do the same thing.

 

+1 on the possibility of having to drill out the pushrod holes. I would also recommend changing out your stock anemic valve springs if changing rockers. You can use LS6 or PAC springs with the special COMP retainers to gain lift on stock vortec heads with no modification. I would not recommend the Comp springs due to many reported failures with the springs, but comp makes the special retainer necessary.

 

So where do you find a 3/4 ton exhaust system? Or a reasonably priced replacement one with teh big tubes?

When looking at higher ratio rockers you also need to be concerned with coil bind or retainer to oil seal clearance. Not a lot of extra room on the stock ones.

 

Junk yards. Any 350 powered 2500 or 3500 through the 2000 model year has the exhaust system you are after. If you want headers at the same time and are willing modify the exhaust a 454 system would work too. No the big block setup will not bolt up directly to your 350's manifolds before someone inevitably asks.....

 

You can get everything from Summit Racing.

pics
Catco rear section $293


Catco front section $347


Walker front section(BBC)


Walker Rear $388


Magnaflow front Cant find a non-Cali cat price for this, but a California approved cat in this style is $600


Magnaflow rear $404


Then there is the Mgnaflow direct fit for a 1/2 ton Vortec 350 which has mandrel bends and is WAY better than the stock overly crimped stock dual 1 7/8" headpipes


$365 for non_California cats
$630 for the California cats


The 454 and HD 350 headpipes are similar except for fitment. Kinda like the GMT800 6.0 and 8.1 exhausts.

A GOOD set of shorties and a nice 3/4 ton exhaust would work wonders for a truck that originally had the stock 1/2 ton headpipes.

PS I did a 355 Vortec with teh GM LT4 hotcam and LT4 roller rockers and had to clearance the pushrod holes.

peace
Hog

 

I've got a set of Skip White stainless steel 1.6 rockers (not self aligning) on the 2.2L in my 95 Corsica (they have heads similar to a baby SBC/BBC hybrid). I spent a lot of time researching them and it seems that most recommend you spend the good money if you buy aluminum rockers.

I'm sure the steel in mine are more brittle compared to aluminum, but they can be made physically smaller than the aluminum versions, with the same relative strength,and fit better under the valve covers. The versions I have are made to fit under centerbolt SBC valve covers and fit perfectly fine under the valve cover of the even more cramped 2.2L. I'm using ARP 3/8" rocker studs for Vortec engines as well (I bought the kit for the 4.3L because I didn't need a full set of rocker studs at the time, to cut costs).

I haven't driven the car yet, still lots of work left to do, but each rocker seemed to be of impeccable quality and came with polylocks, all for less than $140 shipped to my isolated door in Northern Canada.

 

Hey man I’m doing a little work on my 350 that I have Vortec heads on I hope you don’t mind me asking but what set of rockers did you end up going with and I guess some first hand knowledge would be nice and if you have the link or where you orderd them from would help