hghpwr

you are just incredibly lucky at this point,stock springs are just not rated for the extra lift,and to boot the lt4 springs are really inexpensive.

GRIDERMAN87

was told they would hold by my mechanic and the man who made my cam had it in the car for about 7000 miles with no problems, so i figured if they were gonna go they would have gone by now.

pgerst

Found this at http://www.malcams.com/legacy/misc/LT4.htm

"Valve springs are stronger, with a higher installed seat pressure (100 lbs.in. for the LT4 vs. 85 lbs. for the LT1) and wide open pressure (260 lbs. on the LT4) to keep the valves following the camshaft's contours. Special valve springs, eliptical shaped instead of circular in cross-section (Larger horizontal cross section than vertical), allow a spring with a higher free height to be compressed more for higher operating pressures."

Bersaglieri

Good luck with that.

Insert: http://www.youtube.com/watch?v=p8mdq6fzzYM

-Dustin-

GRIDERMAN87

thanks for the well wishes.... car runs and runs well only problems ive had is burning 02 sensors no valve noises nothin so im gonna say it works cause ive done it, im not sayin it is the best situation but if you dont have deep pockets you gotta do wat you can afford, and it will work.

pgerst

1995 Factory Service Manual Spec for LT1 valve springs, (page 6A3A-36) is:

Closed: 81-89 lbs at 1.78"
Open: 252-272 lbs at 1.305"

So it will at least lift to .475. The valve lift is .45 for intake and .46 for exhaust, which would be .015 clearance on the exhaust, which seems to me to be way too tight of a design clearance. Of course, the same guy who designed the optispark may have been promoted to valve trains...

RamAir95TA

What this means in case this thread comes up in the future for someone doing a search is:

You cannot safely run stock valve springs with anything other than the stock camshaft, period.

GRIDERMAN87

im safley doing it right now

RamAir95TA

No, you're not. Simple math and physics tells you that you aren't. Do we have to explain it to you again? Don't post awful advice.

GRIDERMAN87

have you done it ? i have and still drive the car every day so untill you get the experience of actually trying it dont tell me it wont work

RamAir95TA

So many hard-headed new members lately. Ugh.

I chose a different path, and everything I have personally done is done RIGHT, backed by math, extensive research, patience, and good workmanship. The fact of the matter is, your springs are binding and your lifters are getting pounded. A safe limit for coil bind is .030", and you are in the negative. The extra lift is being absorbed by your lifters which are taking a pounding. This is fact - not debatable.

You installed a hotcam on stock springs and stock rockers. That tells me you're impatient and hasty and only cared about getting it installed, not thinking about the consequences. It fired up and hasn't blown up yet, so you have drawn conclusions that it is an acceptable practice to do what you've done. It's not, plain and simple.

I'm done here. I'll let everyone else chime in.

henryz28

I am running the hot cam with the hot cam springs and I think I should have stronger springs. Your car will run and hold up for a while with the stock springs but a few more thousand miles and a few times going wot at say 6200rpms and you will wish you installed stronger springs.

Bersaglieri

This people.

-Dustin-

Ultra_Dog

I went from 260RWHP to 349RWHP with LT4 Heads, cam, intake.

pgerst

I found these specs on the internet:

GM P/N / seat pressure / rate per inch / install height / solid height

LT1 10206040 / 85 / 373 / 1.780 / 1.260

LT4 12551483 / 101 / 332 / 1.780 / 1.220

http://www.gmpartsdirect.com/perform...CATID=734.html

I come up with the following:

LT1 max lift .520 at 279 pounds

LT4 max lift .560 at 287 pounds

My math or the specs from GM could be wrong? Does anyone have an LT1 spring they can measure?