bigarmzz

i'm wanting to put in a GM hot cam in my 92 L98 Z28 Camaro (when weather breaks in spring here). I'm pretty sure i'd need to upgrade the springs and such, just wandering if there's a "cost effective" spring upgrade using the stock heads?

later on i'll be hopefully upgrading other items, runners, exhaust, etc....for now i'm just trying to plan ahead, thanks

bigarmzz

I think I may have answered my own question....anyone know for sure if these would work on stock heads on my 92? it says its for LT1's....

http://www.alexsparts.com/lt1-valve-...s-spring-base/

Orr89RocZ

iTrader: (20)

They should work. Also the vortec kit. May not need to put on new locators tho just use the springs and retainers

Double check the lift capacity

bigarmzz

thanks Orr89RocZ, seems like every time I do a search on cams, or heads your name always pops up

would alex's vortec kit work on my stock heads? or just go with the kit I posted a link to? the "GM hot cam kit" just seems way overpriced in my opinion

I found just the springs from GM
http://paceperformance.com/i-6255251...-diameter.html

Orr89RocZ

iTrader: (20)

Lt1 kit should work. You just may not need to use the spring bases it comes with, depending if it fits over the guide boss and in the pocket.
Else use stock bases and just drop the springs in. They should fit.

The seals should work but not exactly sure on the guide boss diameter on iron Lb9/L98 heads vs alum lt1's. call alexs parts and ask to be sure. I want to say the vortecs have a different guide boss diameter so it may not be the kit for you. Again not positive on that but the springs and special clearanced retainers they have in both kits are the same or close to same so they should drop in on stock pockets

2005Impalla

Those spring have 130 LBs at 1.785" install height so they will have a stiffer seat pressure than that installed. If you want to be cheep I would use LS6 springs with the comp cams 787 retainers. I have a set and have calculated the seat pressure at 127 LBs at a 1.7" installed height. The springs were $55 and the retainers were about the same.

bigarmzz

I read on the web someplace that you can do that on the vortec heads, but wasn't aware this would work on the stock L98 heads

2005Impalla

Ya the heads have the same install height and diameter spring. My Comp springs are the same diameter as my LS6 springs. The only difference is the LS6 springs are designed to be installed 1.8" and the comp cams are suppose to be 1.7"

2005Impalla

Also my springs are blue. The springs use to be sold yellow. I think people use to have problems with the yellow springs breaking.

TTOP350

iTrader: (8)

The stock L98 heads have a exhaust rotator that you can and should remove but u will need to shim the base on the exhaust spring

bigarmzz

Well crap. That complicates things. Wish GM wouldve just made these cars more "easily upgradable"

2005Impalla

Shims are cheep.

TTOP350

iTrader: (8)

Its not a big deal, most shops can tell you what u need and as stated, they are cheap or even free from some shops.

2005Impalla

I want a set of L98 heads. My neighbor has a set on the original motor with an LT1 cam and a factory high rise aluminum intake from the 60s on it. Its a cool mix match of parts. Would be a great motor for some one with TBI if it had an adapter plate on it. I am trying to track down a set of these just to set aside for a later build. Might use them on a spare motor I have. Or they might just sit in my shed with the rest of the other random parts I just had to have for cars I don't own

bigarmzz

for other guys looking to do this for future searches, on the "hotrodders" forum, member "hogg" has verified that this combination will indeed work on vortec heads....

http://www.hotrodders.com/forum/vort...-a-232271.html

there isn't any machine shops around where I live worth a grain of salt, so this may end up being one of those things that i'll just need to continue to research for the stock L98 heads

Orr89RocZ

iTrader: (20)

Shims arent a big deal. Need a spring micrometer to measure install heights and set up to spec.

Damon

The shim needed if you switch from exhaust rotator/retainers to standard retainers (like your intake valve use) is 1/16". Many shims are available in .060" thickness, which is plenty close for a budget effort. You will have to do this NO MATTER WHAT SPRING YOU CHOOSE.

First thing you need to make sure of is that the heads have the retainer-to guide (seal) clearance to handle .491" lift (1.5 rockers) or .425" lift (1.6 rockers) with that cam.

The use of beehive springs and retainers will instantly fix this for you, if you are averse to having any machining done. See Impalla2005's post, above, which is absolutely correct. LS6 springs (dirt cheap) plus the proper retainers (not cheap) will get you home.

If you don't want to go the beehive route and would rather stick with standard cylindrical springs/stock-type retainers, you have two choices- have the guides machined down a little at the machine shop, or do the "ghetto grind" to the underside of the retainers to pick up about .050" more retainer-to-guide clearance. The ghetto grind is actually a perfectly valid operation to accomplish this, it just freaks some people out grinding material off the bottoms of their retainers.

Once you have that sorted out you just need the proper springs. Crane 99845 springs work just peachy with a mild performance hydro roller like the LT4 HotCam (they were designed for LT1 engines, just like the LT4 hotcam was). There are others, of course, that will work as well.

Kevin91Z

iTrader: (1)

What other mods have you done? A cam swap is not the first thing to do, and the LT4 hot cam is way too big for a stock engine. You *WILL* need custom chip programming to run that cam. I started doing my own chips when I used that cam in my engine way back when.

Manley 22410-16 spring and 23652-16 retainers will allow you to run the hot cam with 1.5 rockers (.492" lift), but again I don't recommend it. Also, since you have to pull the intake manifold, you should seriously consider getting an Edlebrock TPI one to replace it.

The ZZ4 cam will run much nicer with the stock computer, as well as several other cams in the 210* range.

2005Impalla

Ya I agree the LT4 cam alone would be a bad mod but a cam is the first thing I would do to a motor. A smaller cam on its own can give more power alone than any other single part. At least this is true for a carbureted motor. I don't mess with fuel injection on V8s. Have modified quiet a bit of 4 bangers but all my fast V8 are carbureted. Other than heads a cam is my favorite part to change. A motor is not modified tell you replace the cam