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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
Sounds like an awesome build!! What's not to like??? Also, I really like you're staying with 8mm rocker bolts. I think people are sometimes carrying a bit of original SBC tech into the LS arena. I did for a bit. Anyway, if it was an 8mm rocker STUD, YES, that would suck. But it's NOT, so it doesn't!! That 8mm (probably a 10.9 fastener) bolt can apply tons and tons of pressure to keep the rocker in its 'nest'. 450-500lb springs OTN won't phase an 8mm, 10.9 bolt in the least. Haven't looked up the tensile strength, or the amount of force it can apply. But I do remember a 1/4-20 nut can apply many tons of pressure, and the 8mm is much beefier yet. My LS7 has a bit smaller cam than yours. It's a Futral/Cam Motion grind. Mine has .603"/.608" lift, duration is 232°/250°, LSA is 112°, +4°. It has 17° overlap. As for streetability, I get 21-22mpg on the expressways, 14-15 around town, and its an A4 vert with a 3,200 stall Yank. Very little problem with bucking/surging. No, I'm not here to tell you it drives "just like stock", because it doesn't. But it does drive EXACTLY like stock once you're at any speed over 55mph in OD.....EXCEPT for the acceleration part!!! TRUTH!!! Best of luck on your build......
THANK YOU!!! I greatly appreciate that.
Yeah I was thinking about going to 10mm bolts but decided against it. Bigger is better when you go big enough to need better. That is one thing I didn't have an issue with when I was on the oem cyl head. I was running stock rockers with pac .660" dual springs and never had an issue with the bolts.
The Manley NexTek springs I am using have a good seat pressure to keep both 101g hollow stem Intake
Valve and 98 g Solid stem exhaust valve stable without putting too much strain on the rocker assembly. If I were to have gone with a 124 g Intake valve then I could see the potential need for a 10mm YT set-up.
If you think about it the Rocker bolts dont really "hold" too much pressure. The just keep the Rockers in place. Plus the Yella Terra rockers mount both intake and exhaust valves together to keep the geometry stable. And any excess pressure built up is relieved by the lifter. The mount and perch basically maintain the pivot point for the rocker to swivel on. And the; (i am going to use this term loosely); "trunions" allow for the pivot to happen. If the 8mm bolt wasn't enough clamping force the 22ft-lb rocker bolt torque spec would be higher or a larger bolt would be required.
But even when I had my last build I had ZERO issues with the stock rocker perches, Stock rockers with CHE Trunions, and re-used 8mm bolts from my last "head fix" and cam package TWICE lol. If anything just for continuity purposes; I will more than likely get a set of ARP bolts if the rockers don't already come with them and I imagine I will be fine.
These are the reasons why I chose to stay w the 8mm YT setup.
Here are the specs from the springs I am using:
GM LS-series high performance hydraulic roller applications.
Type of Spring: Polished Double Coil without Damper
Color Code: N/A
Installed Height and Pressure: 1.810'' @ 170 lbs./in.
Open Height and Pressure: 1.110'' @ 450 lbs./in.
Spring Rate: 394 lbs./in.
O.D. of Outer Spring: 1.340''
I.D. of Outer Spring: 0.994''
I.D. of Middle Spring: N/A
I.D. of Inner Spring: 0.726''
Coil Bind height: 1.050''
Weight: 94 grams
Damper Included: No
I imagine these springs will give me more than enough seat pressure and open pressure to keep the valvetrain stable all the way up to 7,700 rpm's.
Our cams are VERY similar. Have you had yours on a dyno yet? I am dying to know what kind of power this will put down.
I had to throttle back on this build a bit because I will be moving across country in a few months.
This cam is definitely larger than the TSP 2.2 cam I had in it before. So I am aware of the street ability factor lol. But it isn't a daily driver; I did take bucking into consideration and I added .5* of LSA and +4* timing to soften that a "little" but I will see how well the parking lot mannerisms can be adjusted in the closed loop idle tune. I don't anticipate all bucking can be mitigated, because the last setup bucked like crazy. But then again I did have an ACT 6 puck unsprung race clutch in it that had 1/8" slip zone on the pedal. Felt like I was doing a leg press every time I put my foot into the clutch. Not to mention the ACT Wailed like a Banshee. But I will say some great things about that clutch; even though it was more like a on off switch rather than a clutch. It never slipped, it never felt mushy and it always took all the abuse that I could throw at it. From a 3,500 dig or a 1st gear 40 roll. That was an experience of its own.
These are MAMO stage 1 heads and are set up for a 11.5:1 comp ratio which flow 406 cfm flow bench verified. With some milling and .010" shaved off the head gasket.
I will eventually be getting a Ported MSD... but I am under TIGHT time and financial restraints and 1month behind on time at the moment and am happy with the decisions here-in.
My previous build I was planning to do with Tony was in the ballpark of 12.0:1 compression for 100+ octane. Same .010" off the head gasket but .028" more off the heads and more port work too. To include a nice set of Ti-moly intake valves and hollow light weight exhaust valves.
The cam I had on order before I had to throttle back because of move.
111LSA 241 / 255 114 .675" (20' Overlap) W / 1.8:1 rocker ratio accounted.
So I am right about the middle of where I wanted to be. I am EXTREMELY happy with this build and with Tony's help and communication.
There WILL be another cam install and more head work done to these heads in the future. And also more upgrades to support.
crazy how a 600wph car can make 20+ mpg on the highway. LOL. Love it!!!
You realize a 8mm bolt can probably hold the weight of the entire car in tension right lol it absolutely sees ALL of the load that the springs, cam, and ramp rate gives. Have those valves been spintron tested by chance? Curious as I’d like to keep my 7500 limit but not sure of many packages that went up there without having to run insane pressures. Thanks!
Yeah I was thinking about going to 10mm bolts but decided against it. Bigger is better when you go big enough to need better. That is one thing I didn't have an issue with when I was on the oem cyl head. I was running stock rockers with pac .660" dual springs and never had an issue with the bolts.
The Manley NexTek springs I am using have a good seat pressure to keep both 101g hollow stem Intake
Valve and 98 g Solid stem exhaust valve stable without putting too much strain on the rocker assembly. If I were to have gone with a 124 g Intake valve then I could see the potential need for a 10mm YT set-up.
If you think about it the Rocker bolts dont really "hold" too much pressure. The just keep the Rockers in place. Plus the Yella Terra rockers mount both intake and exhaust valves together to keep the geometry stable. And any excess pressure built up is relieved by the lifter. The mount and perch basically maintain the pivot point for the rocker to swivel on. And the; (i am going to use this term loosely); "trunions" allow for the pivot to happen. If the 8mm bolt wasn't enough clamping force the 22ft-lb rocker bolt torque spec would be higher or a larger bolt would be required.
But even when I had my last build I ZERO issues with the stock rocker perches, Stock rockers with CHE Trunions, and re-used 8mm bolts in my last "head fix" and cam package TWICE lol. If anything just for continuity purposes; I will get a set of ARP bolts if the rockers don't already come with them and I imagine I will be fine.
And that is why I chose to stay w the 8mm YT setup.
Here are the spring specs:GM LS-series high performance hydraulic roller applications
Type of Spring: Polished Double Coil without Damper
Color Code: N/A
Installed Height and Pressure: 1.810'' @ 170 lbs./in.
Open Height and Pressure: 1.110'' @ 450 lbs./in.
Spring Rate: 394 lbs./in.
O.D. of Outer Spring: 1.340''
I.D. of Outer Spring: 0.994''
I.D. of Middle Spring: N/A
I.D. of Inner Spring: 0.726''
Coil Bind height: 1.050''
Weight: 94 grams
Damper Included: No
I imagine these springs will give me more than enough seat pressure and open pressure to keep the valvetrain stable all the way up to 7,700 rpm's.
Our cams are VERY similar. Have you had yours on a dyno yet? I am dying to know what kind of power this will put down.
I had to throttle back on this build a bit because I will be moving across country in a few months.
This cam is definitely larger than the TSP 2.2 cam I had in it before. So I am aware of the street ability factor lol. But it isn't a daily driver; I did take bucking into consideration and I added .5* of LSA and +4* timing to soften that a "little" but I will see how well the parking lot mannerisms can be adjusted in the closed loop idle tune. I don't anticipate all bucking can be mitigated, but the last setup bucked like crazy and I had an ACT 6 puck unsprung race clutch in it that had 1/8" slip zone on the pedal. That was an experience.
These are MAMO stage 1 heads and are set up for a 11.5:1 comp ratio which flow 406 cfm flow bench verified. With some milling and .010" shaved off the head gasket.
I will eventually be getting a Ported MSD... but I am under TIGHT time and financial restraints and 1month behind on time at the moment and am happy with the decisions here-in.
My previous build was in the ballpark of 12.0:1 compression for 100+ octane. Same .010" but .028" off the heads and more port work.
The cam I had on order before I had to throttle back because of move.
111LSA 241 / 255 114 .675" (20' Overlap) W / 1.8:1 rocker ratio accounted.
So I am right about the middle of where I wanted to be. I am EXTREMELY happy with this build and with Tony's help and communication.
There WILL be another cam install and more head work done to these heads in the future. And also more upgrades to support.
crazy how a 600wph car can make 20+ mpg on the highway. LOL. Love it!!!
stay tuned....
Yes, it was dyno'd@617hp@6,300rpm, 565ft/lbs@5,000rpm, on a dynojet, and just over 500whp on a Mustang. Tuner said I'd have been around 520-525whp if it was a manual trans. I know there's a lot on the table, but I put 10,000 miles yearly on my car. Plus I've got OEM heads, so there's that!!
Yes, it was dyno'd@617hp@6,300rpm, 565ft/lbs@5,000rpm, on a dynojet, and just over 500whp on a Mustang. Tuner said I'd have been around 520-525whp if it was a manual trans. I know there's a lot on the table, but I put 10,000 miles yearly on my car. Plus I've got OEM heads, so there's that!!
10,000 miles yearly on a Z06 ? That’s great man...I’m guessing you don’t live in NY....Living in NY and owning modified corvettes has its drawbacks ....There’s no way I’m using my Vette as a daily driver ..
Traffic was always heavy in NY but after Covid it’s on a different level...It’s insane...My Z is out very early on a Saturday or Sunday and back in the garage by 10 am and I’m retired.Go figure..
Do take the Z on car events out of state when they come up..Carlyle ( which they really should have in the spring ..Late Aug it’s too damm hot ) Ocean city MD , Wildwood NJ car cruise...
Good luck with the rest of that build ..I’m jealous of all you guys that live where there is not a stop sign every 500 feet...Cheers
10,000 miles yearly on a Z06 ? That’s great man...I’m guessing you don’t live in NY....Living in NY and owning modified corvettes has its drawbacks ....There’s no way I’m using my Vette as a daily driver ..
Traffic was always heavy in NY but after Covid it’s on a different level...It’s insane...My Z is out very early on a Saturday or Sunday and back in the garage by 10 am and I’m retired.Go figure..
Do take the Z on car events out of state when they come up..Carlyle ( which they really should have in the spring ..Late Aug it’s too damm hot ) Ocean city MD , Wildwood NJ car cruise...
Good luck with the rest of that build ..I’m jealous of all you guys that live where there is not a stop sign every 500 feet...Cheers
Not exactly a Z06. My LS7 is in a 2000 C5 A4 vert, 125,000 miles, and climbing.......
You realize a 8mm bolt can probably hold the weight of the entire car in tension right lol it absolutely sees ALL of the load that the springs, cam, and ramp rate gives. Have those valves been spintron tested by chance? Curious as I’d like to keep my 7500 limit but not sure of many packages that went up there without having to run insane pressures. Thanks!
I agree about the 8mm bolts...
The way I understand it is, the OEM castings also use 8 mm bolts and are mounted on raised perches. I have not seen any OEM perch's cause issues. So I decided that if those perches can withstand the pressures of the valvetrain using 8mm bolts; then the trickflow specialties mounting surface being flat should offer a lot more clamping force being screwed directly into the heads.
And when I initially started this build I spoke with Trickflow. The rep stated that their head setup has been spintron tested as stable to 8800 rpm with the valve and spring setup they use. Their intake valves weigh around 115-118 g if I remember correctly. And the valve springs are rated to 450lb open.
So when I went to Tony I specified that the car sees top end runs... from dig races to 1st gear 40 rolls and 2nd gear 60's. I explained that I wanted the lightest SS HOLLOW intake and solid stem stainless exhaust he could offer. I was specifically searching for SS because I wanted AND still want to stay away from a ti-moly valve.
With that in mind he put the package I have together ... a 101g intake and a 98g exhaust valve that is not only lighter than competition, but thanks to friction welding the valve stems are much stronger because both metals rub against each other and are bonded together as one piece.
His stage 1 head package offers some of the lightest stainless steel hollow stem intake valves available.
As you see above the Manley NexTek valve springs give me enough open spring pressure and the inner spring gives enough pressure at the seat to keep the valve stable and keeps it from double slapping at high RPM's.
I doubt I will go passed 7,500 rpm but the car will see 7,500 on the tach quite a bit.
Tony at MAMO Motorsports (MMS) and I spent 15-20 hours talking about the best possible combination to meet my needs.
And hopeful that in the next few days I will take delivery of these heads and anticipate the first start up in 2 years to me mid May...
here is a great video of what the process looks like.
https://youtu.be/cKv0x7VZecs
she even screams with orgasmic sounds from the rear and rarely makes bitching sounds when she not happy but that look never goes away
No .... No it doesn't
I started cleaning the block. Pics to come, heads, Johnson lifters, New clutch slave cylinder, Harmonic balancer, Mantic clutch assembly kit, YT rockers, thick valve cover gasket set and .040" head gaskets to be received by May 1. I'm So close I can almost smell the exhaust fumes.
I got a new set of mounting hardware from Mantic Clutch USA .. for the clutch re-install. Im going to install a new pilot bearing prior re-assembling the clutch .
10,000 miles yearly on a Z06 ? That’s great man...I’m guessing you don’t live in NY....Living in NY and owning modified corvettes has its drawbacks ....There’s no way I’m using my Vette as a daily driver ..
Traffic was always heavy in NY but after Covid it’s on a different level...It’s insane...My Z is out very early on a Saturday or Sunday and back in the garage by 10 am and I’m retired.Go figure..
Do take the Z on car events out of state when they come up..Carlyle ( which they really should have in the spring ..Late Aug it’s too damm hot ) Ocean city MD , Wildwood NJ car cruise...
Good luck with the rest of that build ..I’m jealous of all you guys that live where there is not a stop sign every 500 feet...Cheers
Thanks for that,
For the time being the car will retain the OEM manifold,OEM injectors, and a MAMO ported silver blade TB. I am keeping it on pump gas for now too.
I am aware that the OEM Manifold will be a choking point but, this will allow the car become drivable in the shortest time available. And will allow me the time I need to move across country.
Taking the OEM manifold, and injectors into consideration, I wonder how close to 600 whp I will get seeing these heads flow 406 cfm on a flow bench and the cam has more lift, more duration, more overlap, more timing, More ICL, and more LSA added.
TSP lift .635/.635 w/ 1.8:1 rocker ratio
Mamo lift .648/.648 w/ 1.8:1 rocker ratio
difference .013" lift
TSP duration @ .050” lift 234 int / 246 exh MAMO duration @ .050" lift 237 int / 251 exh
difference 3* int / 5* exh
The heads are minimally milled and am also taking .010" off the head gasket thickness. So that should help bump the compression up to 11.5:1.
Knowing what I made before cam only 535/499 91oct I will have a good comparison between a cam only Z06 on stock intake, stock injectors and stock TB to a heads / cam Z06 with stock manifold, injectors and ported OEM TB.
Taking a look at the numbers above and the limitations I have I predict my the CURRENT setup to make around.
575 whp / 520 ft-lb tq.
This will allow me to set a good baseline and work my way up from there if I feel the car needs more.
Anyone care to take a guess as to what it will put down?
Don’t uses arp fly wheel bolts(buy factory) people have had issues rubbing their clutch on a mantic clutch.and for add insurance I would get locking nuts for the clutch assembly.
Don’t uses arp fly wheel bolts(buy factory) people have had issues rubbing their clutch on a mantic clutch.and for add insurance I would get locking nuts for the clutch assembly.
Thank you for the great advice!
I had spoken with Mantic about that. They said NOT to use the 330-2802 that is recommended because of this look at the red circle.
these are the ones that Mantic recommends
I will go and find some locking nuts for the clutch.
Yes, it was dyno'd@617hp@6,300rpm, 565ft/lbs@5,000rpm, on a dynojet, and just over 500whp on a Mustang. Tuner said I'd have been around 520-525whp if it was a manual trans. I know there's a lot on the table, but I put 10,000 miles yearly on my car. Plus I've got OEM heads, so there's that!!
that is a really significant whp difference between mustang and dyno jet... i wonder why
Don’t uses arp fly wheel bolts(buy factory) people have had issues rubbing their clutch on a mantic clutch.and for add insurance I would get locking nuts for the clutch assembly.
thank you again for the advice!!! I got a new set of OEM flywheel bolts
04-15-2022, 08:38 PM
TRUTH!!! Best of luck on your build......
