RootBreaker

Ok first is first.. this is for a non camaro/computerered vehicle...

I can lead you to a big thread to start you off and confuse you as bad as I am...
http://www.pavementsucks.com/forums/...hp?topic=79630

this one had alot more opinions.....
http://coloradok5.com/forums/showthread.php?t=150014

Ok so background...
1991 chevy caprice 350 (9C1 series)
hydraulic roller cam/lifters
cast heads
tbi
manifolds
single exhaust
computer controlled

now:
1991 chevy caprice 350 (9C1 series)
hydraulic roller cam/lifters
cast heads
1989 camaro z-28 intake (dual plane)
holley truck avenger 670cfm carb
full tube headers
dual exhaust
non computer controlled (in a 1978 chevy pickup)

anyhow what I need to know is how to pep this motor up...
I dont want a 4mpg runner 400+ hp... just want enough to get around and be happy...

so I was told vortec heads will flow alot better.. well then I also could drop a nice intake on there..

so vortec heads and performer intake...

well while down there maybe swap cam???
so I found a comp cams xtreme 4x4 cam...
people tell me to run that cam... .474 lift with vortec heads you need to run z-28 springs and lt4 retainers... then you can run up to .510 lift cam...
I am trying to do this CHEAP!!!
I did find a lunati 54760 cam... .471 lift and the tech there told me that the gm manual says you can run up to a .475 lift cam on vortecs....


ok so I dont know anything about this stuff.. if something is broken I can replace it... but what to do here..

looking for off the line torque and hold the torque long.... so idle - 5000 for power...

Thanks

90rocz

Vortech heads require a Vortech intake b/c of 1/4" taller intake ports, gasket won't match either.
GMPP ZZ4 cam is very streetable, Vortech heads might require machining to support over .480" lift(??)
I'd use a single plane Torker style intake and a 600cfm carb, the small car with and "open" intake gives you low end pull plus high end rpm. (Your cyls will see a full 600rpm, not just one side of the 670 or 335..)
Or Comp Cams XE 268...

Damon

I think you did a good job sifting through all the info that was thrown your way. The basic "bottlenecks" of a TBI motor like you've got are the heads and cam.

Vortec heads would be a good upgrade over the "swirl port" 350 TBI heads for flow and combustion efficiency.

Like was suggested above, the ZZ-4 cam (208/221* duration on 112* LSA) would be a good choice for what you're after with just a smidge of performance to it. But so would a stock LT-1 cam (204/208* duration on a 116* LSA or thereabouts, if memory serves). Another alternative would be a stock LT-4 cam (not the LT-4 Hot Cam). Any of them should be used with 1.5 rockers to keep from maxing out the stock Vortec's lift limits. ANY of these cams is a fire-breather compared to the stock TBI cam (which has about 10-15* less duration and quite a bit less lift across the board). This does NOT mean you'll tank your mileage or low-end torque. These cams will pick up everywhere compared to your TBI cam. Mileage would probably be almost unchanged. The aftermarket is always available to meet your needs, too.

I disagree about using a single plane intake, however. Dual plane intakes were designed for applications exactly like what you're considering.

RootBreaker

appreciate your replys guys...

so you think a stock cam that you list above plus the vortec heads will give me a world of difference....


I may be getting a 1998 350 with vortec heads saturday...... if so Ill most likely keep that entire engine.... then drop a cam that you list above and all my goodies on it...

Thanks

RootBreaker

think the hi lift heads "906" and intake by a member here would do good? they are on ebay right now... thinking of them... those heads/intake and a cam plus gaskets.. and id be good???
thanks
Jeff

RootBreaker

yeah I read that article... but they bought them already done up...

I can get a used set of vortec heads.. 50k miles... $200 and it is local....

so so many people say different sizes that you can run for lift of cam..... what is the big deal of using z28 springs? does that mean they are stronger and can be compressed more? direct swap?
lt4 retainers... what are retainers and what do they do....

I am told z springs and I can run up to .480 lift cam.. I want a .474 so that is close....

sorry bout the dumb q's...
and appreciate all the help

90rocz

Not sure of which springs the "Z28 springs" are?? But I am using the "Orange-Code" springs for the "ZZ" motors...


They allow you to run more lift by,
1)Made stronger for higher lift, helps prevent the valve from bouncing back off the seat.
2)Less coils, so the the compressed height or "solid" height, allows higher lift without maxing out the coils and binding and bending pushrods.
3) "Retainers" are at the top of the springs that hold the spring to the valve by the "Locks", 2 small angled keepers some 7* some 10* etc..

To find which springs will support your lift, subtract yoursolid height(1.16" above) from the installed height(1.70"above) plus an additional .010" per space in the coils,(.040" above)= about .500" safely, but can push to the .510" of the ZZ4 cam w/1.5 ratio rockers with reasonable safety.
It's always best to get tech support for the correct spring for your application tho, no sense reinventing the wheel.

confused327

http://chevyhiperformance.com/techarticles/76178/
check out that whole series i think that is kind of what you want

RootBreaker

i know this is old but wanted to update...

since this is a truck and not a car.... I want power down low...
I was looking at a comp cams xtreme 4x4 cam - .474" lift
http://www.compcams.com/Technical/Se...umber=12-411-8

after talking to the guy at summitracing we opted for the next size down... .458" lift
http://www.compcams.com/Technical/Se...umber=12-409-8

lost some hp and torque however the cam I chose was power at idle as the other was like 1200rpm's or 1500rpm's

all I can say is WOW!!!! with that cam I chose... vortec heads, weiand power plus+ intake and my truck avenger 670cfm carb.... this thing MOVES now...

1/4 throttle is better than what full throttle used to be.. I still have a hesitation in the carb.. just have to change out the accelerator pump cam.....

I used to take off and the truck would just go.. it isnt a race car but now I can actually launch and get thrown back into the seat throughout the gears.... L, 1, 2 then drop in 3rd and feels so much better.....
I have 6" front leafs that sag down to 5" (softrides) and 1" ord zero rate... I can actually feel the truck lift up (springs flexing) as I accelerate...


Thanks for all the help guys.... I was going to modify the heads to accept a bigger cam but then i will eventually get to too many rpm's to make the power meaning time to slip the clutch and all......

Also I was told unless you are at high rpm's 2.02 valves will hurt torque than help...... dunno how true but oh well....

machine shop wanted $300 to cut the valve guides, enlarge spring seats for z-28 springs and pull pressed instuds and tap for screw in studs.. then I would need to buy the studs and springs.... so $450 I didnt have extra to add.............


thanks again guys....

all this extra power = more room to play harder....




I managed to get behind this guy so he could use my bumper to step on to hookup the strap....
I am 5'10" and the crud was up to our wastes if we were treading it.... the extra power plus detroit lockers front and back, coupled with a snorkel makes for some nice fun.....

RootBreaker

so need some help.. getting my truck legal.... i need the serial number off the motor...have to add to title...

so
all i can find is behind the head... on passenger side..

can someone decode this for me?

I want to make sure i have the right numbers..

R063938

thanks
Jeff