maybe2fast

iTrader: (4)

1995 TA M6

I just had the heads done:

3 angled
ported and polished
lt4 springs
7 thousands decked
new valve guides
teflon valve seals
media blasted (they look so nice)
Hotcam
madz28 tune
1.6 RRs
LS1 DS
Edelbrock headers, with no cat
magnaflow CB
magnacore wires
MSD cap and rotor
AIR delete and EGR delete
K&N system, airfoil, TB bypass
new Timing chain

T56 went through
viper syncros
steel fork
short stick


what do you think I will put down? and run in the 1320?

streetwarrior96

330 to 350 rwhp

96capricemgr

iTrader: (1)

So you figure out what you are doing for springs in a few months when those are no longer sufficient? I know they are "supposed" to be right but reality and what everyone says are often two different things.
Heads are a tough thing to guess on a shop literally can port and do a 3 angle and hurt performance or another shop might find you 70+hp in the porting alone.

mightyquickz28

iTrader: (8)

I believe what 96Capricemgr is referring to is the fact that the LT4 springs are meant to control the lighter, sodium filled valves that came in the LT4, not the much heavier LT1 valves. You may see valve float at high RPM since the open spring pressure may be overcome by the inertia of the heavy valves.
Otherwise, I agree with the HP forecast of the other post. I had home ported heads with the LT4 HOT cam, LT4 1.6 roller rockers and crane 10308-1 spring kit. Dyno'd thru a full factory stock 96 exhaust system(gutted twin catalytics), I got 347rwhp at MTI's dyno. At the Houston drag strip, full street weight (3,650lbs) and on Firestone Firehawk 245x50x16 Tires on all four corners, I turned 1.9 sixty foots, 12.8x at 109mph on back to back passes. The car had the stock 3.42 10 bolt and T56 transmission.

maybe2fast

iTrader: (4)

thanks for the estimate! I am DDing the car so high rpms will be minimal

Shon Herron

iTrader: (25)

350ish
LT4 springs are marginal, even for the HOT cam.

maybe2fast

iTrader: (4)

well with them being installed with all the hardware that came with the kit they were not installing at the right height. around 1.73 and that was not good. I purchased some different keepers and they installed correctly and at the right height. I wonder if people with the kit are wearing out springs due to this proplem of the wrong installed hieght. needless to say they are at 1.78 now and at 99-101 lbs.

350ish

12.8 woudl be tight

96capricemgr

iTrader: (1)

OK so I change my comments you will have float problems right out of the gate.

Shon Herron

iTrader: (25)

Why set you sites so low, i had a street car with the hot cam at 3400#s go 11.96@112 and the NX100 kit went 11.16@119.9

maybe2fast

iTrader: (4)

man, are you negative...and scaring the **** out of me! and at 1.73 I think coil bind is a for sure. A budget is a big factor for me and LT4 spring fit. I can't believe they will wear in a matter of months. they are a factory part and made of decent materials...I hope.

negative or honesty, I hope just hate for LT4 springs.

maybe2fast

iTrader: (4)

I am not setting my sights low. I am hoping this car just hauls ***...with no valve float.

mightyquickz28

iTrader: (8)

THe LT4 Springs were designed to handle the lighter sodium filled valves of the LT4. It's not that they wear excessively, it's just that they weren't designed to handle the heavier mass of the non-sodium filled valves. That's all he means. Not a hater or a pessimist. Just stating a shortcoming in the ability of the LT4 springs so you can decide if you want to risk floating a valve and having a piston kiss a valve at High RPM's.

METALBEAST

iTrader: (1)

Should put down around 340-350 RWHP. I had some ported heads from More Performance and a Hot Cam in my 92 Vette A4. With shorties, !CATS, CB K&N and PCM for less tune, I ran high 12s@108. When I sold it to my friend and we swapped the gears to 3.73s, It trapped 114.2 on a cold pass in March of 2006 at Atlanta Dragway. Ran a 12.5@110 with a 1.86 60' on a hot pass that May.

slick1851

So who ported the heads? flow numbers blah blah

Just having ported heads means nothing, in the wrong hands you can loose power

mightyquickz28

iTrader: (8)

Will Garza ported mine. LT1 Stock castings. LT4 sized Ferrera Stainless Steel. Ported for $1,000 which included the cost of the valves and 5 angle valve job. Will has a flowbench and said they were flowing 275/195 on I/E respectively. Ever the skeptic, I immediately took them over to GTP (Gallant Technical Performance) where Craig (Owner) looked at them and praised Will's work. He picked a random cylinder and found they flowed within 2cfm of the stated figures Will gave me. That was $50 for nothing I guess. I shoulda believed Will.
I now have two sets of these heads. One set on the '94 383 and the other set on the '96 383.

SK.LT1

I believe that as a daily driver, you should not have any problems with these springs.Just drive it and enjoy.

maybe2fast

iTrader: (4)

I originally installed the LT4 springs at 1.78. with using the locks from the kit I got 1.73-1.745 not good. I needed different locks to get the LT4 springs to 1.78. now with that being said, I don't want any problem i.e. VALVE FLOAT. So I want to do 918s and I am trying to figure out what parts to get so I don't have a problem with the install height again. I need the 918s at 1.75-1.78 no higher. what do you suggest I get so I don't have to wait for more parts and dick around. thanks. part numbers if possible.

maybe2fast

iTrader: (4)

another question...I have all the **** for the LT4 springs, is there a spring that I can just replace the LT4 ones and use the hardware I have! that would be great! I will post a new thread about this.