I've been doing a lot of research lately and felt this is another good piece of information to share with the community. It may have already been posted but I didn't find it. I wanted to know what the difference between the 78lb kit and the 75lb kit are from Supertech. The 78s were discontinued for ecotecs a few years ago and replaced with the 75's. Though, they still make the 78s and they can be had if you call Supertech directly (I needed to replace just one from an otherwise good kit). I called Supertech today and this is the information I got:
The only changes between the 78lb kit and the 75lb kit are the retainer, the seat pressure of the spring, and installed height due to the retainer differences. The springs are identical in physical dimension. The reason the retainer was changed is because in some cases they slightly contact the machined lsj followers. Dave made a thread about this
HERE.These followers can also be found in 2005 l61s, I believe only on the exhaust side. Any 02-04 eco will have the stamped followers that, while supposedly weaker, should not have this issue. In no documented case I could find has this contact ever lead to a failure, or even any noise, but the scoring can be seen visually when you pull the cover. Most report that you can't even feel the scoring with your finger because it's so slight.
That being said, the 75lb retainer is dished a little more to eliminate this contact and moves the installed height to something like .010 shorter(I can't remember exactly). That's why the spring is lighter. Moving the installed height down increases the seat pressure.
So, the 75lb Supertech retainers CAN be run on 78lb Supertech springs but since they reduce the installed height and therefore the seat pressure, the springs become more like 82lb (guestimate from the Supertech technical associate). Also, since the retainers are titanium they're about 200 bucks directly from Supertech for 16 of them. The other option, as many have done, is to clearance the machined followers ever so slightly to eliminate this potential contact. Although it's not much I personally find that a little scary as these followers are still pretty weak as it is.
Anyway, that's the deal. Hopefully this helps some people out in the future if they come across the 78lb springs.
"In Oldskool we trust"
Scorpio1 (James K.) wrote:Good info, thanks bud.
I do what I can! Was wondering if anyone saw this or not lol
"In Oldskool we trust"
BTW, i could probably be talked out of the 78lb kit that i have sitting on my shelf.
Tinkles(KGM) wrote:BTW, i could probably be talked out of the 78lb kit that i have sitting on my shelf.
Incidentally the kit I bought from Derek was Matt's old kit which, as you know, had 1 bad spring from running apocalypse cams.
"In Oldskool we trust"
Great info!
Now if I could only get the damn things to quit tearing up super techs valve guide seals with my comp stage 3 cams I'd be set!
Any ideas are welcome
2.2 L Ecotec, P&P Head, Stage 3 Comp Cams, Supertech 76 lb Spring kit, Supertech Oversized Valves, Wiseco 8.9:1 CR Pistons, Eagle H-Beam Rods, Home-Built Turbo Kit T3/T4 57 Trim Intercooled, 78 lb/hr Racetronix Hi-Z injectors, Aeromotive FPR, Racetronix f body fuel pump,MEGASQUIRT MS3 + MS3X Finally street tuned on 21 lbs! Now if only I could get it to hook....
Wes Gardner wrote:Great info!
Now if I could only get the damn things to quit tearing up super techs valve guide seals with my comp stage 3 cams I'd be set!
Any ideas are welcome
Most of us ran stock valve seals with the 78's and various Comp grinds. Everyone that ran the supertech seals seemed to have leaking issues
At least they only leak when the engine is running. I won't have an issue with leaks.
On the inside my car looks like a fighter jet.
Rob Dotterer wrote:At least they only leak when the engine is running. I won't have an issue with leaks.
only you rob lol
"If one day the speed kills me, do not cry because I was smiling." - Paul Walker
I've been running the supertech seals with my engine and have had no problems whatsoever.
Currently #4 in Ecotec Forced Induction horsepower ratings. 505.8 WHP 414WTQ!!!
Currently 3rd quickest Ecotec on the .org - 10.949 @ 131.50 MPH!!!
Come to find out the supertech seals require a grooved valve guide (which they also sell) otherwise they run the risk of coming off the guide. I was also spinning up to 8k+ regularly (i.e. daily)
2.2 L Ecotec, P&P Head, Stage 3 Comp Cams, Supertech 76 lb Spring kit, Supertech Oversized Valves, Wiseco 8.9:1 CR Pistons, Eagle H-Beam Rods, Home-Built Turbo Kit T3/T4 57 Trim Intercooled, 78 lb/hr Racetronix Hi-Z injectors, Aeromotive FPR, Racetronix f body fuel pump,MEGASQUIRT MS3 + MS3X Finally street tuned on 21 lbs! Now if only I could get it to hook....
RET-TS5.5/T5 Is the part number for the 75lb retainers.
Tinkles(KGM) wrote:RET-TS5.5/T5 Is the part number for the 75lb retainers.
I thank you, good sir. Did you end up buying just the retainers from them?
"In Oldskool we trust"
Not yet, they are in the "shopping cart". I haven't clicked buy yet. I figure that I'll let them sit there for the afternoon before I actually buy them.
Still on the 78s (2nd head) still no issues.
Currently #4 in Ecotec Forced Induction horsepower ratings. 505.8 WHP 414WTQ!!!
Currently 3rd quickest Ecotec on the .org - 10.949 @ 131.50 MPH!!!
Good info mate!
I run the 78s. After the first motor teardown I noticed the contact. After filing the followers haven't had any issues since.
You drive a cavalier? Why yes... yes I do.
Tyler Ewy wrote:Good info mate!
I run the 78s. After the first motor teardown I noticed the contact. After filing the followers haven't had any issues since.
Word. I'm told that works great. Just makes me nervous because those things are weak to begin with.
"In Oldskool we trust"
The thing that I am aware of with my car is leakage. That's why I always see to it that it's well-maintained.
Tinkles(KGM) wrote:Not yet, they are in the "shopping cart". I haven't clicked buy yet. I figure that I'll let them sit there for the afternoon before I actually buy them.
10 months later and I still haven't bought them.....
I need to.
