Roller Rocker noise on VY

[mgrb1211]

I've just had high ratio roller rockers fitted to my VY. These are 1.98:1 from Mace Engineering Group. My car now sounds like an old sewing machine. Is this normal? The car has done 600km since I had them installed and its not as noisy as when I first put them on...nevertheless, its still noisy.
Appreciate any advise/opinions on this.

[OZ38]

I've just had high ratio roller rockers fitted to my VY. These are 1.98:1 from Mace Engineering Group. My car now sounds like an old sewing machine. Is this normal? The car has done 600km since I had them installed and its not as noisy as when I first put them on...nevertheless, its still noisy.
Appreciate any advise/opinions on this.

Are these the reworked stock rockers like FIT used to sell ?

If so then FIT used to say they were not suitable for the series II VY V6 engine as the heads had a bigger than normal cast flash left on them. I believe the stock push rods would rub on the casting flash. FIT's answer was to sell you some smaller diameter push rods, but then you obviously had to pay more again for them.

Some engines also bent the pushrods by using these as they must have got hot on one side with the constant rubbing. I would pull the rockers off & check for marks on the push rods.

Cheers

Deek

[aza03]

yeah the mace rockers are reworked standard. i just put 1.9:1 on my vy on Saturday and i am getting the same noise i am not very happy it sounds ****.

[mina_783]

Should have gone Yella Terra

[mgrb1211]

Are these the reworked stock rockers like FIT used to sell ?

If so then FIT used to say they were not suitable for the series II VY V6 engine as the heads had a bigger than normal cast flash left on them. I believe the stock push rods would rub on the casting flash. FIT's answer was to sell you some smaller diameter push rods, but then you obviously had to pay more again for them.

Some engines also bent the pushrods by using these as they must have got hot on one side with the constant rubbing. I would pull the rockers off & check for marks on the push rods.

Cheers

Deek

I have a series 1 VY V6. The Mace rockers are reworked stock rockers although they came with pushrods. So they're not meant to sound like an old sewing machine then?

[mgrb1211]

yeah the mace rockers are reworked standard. i just put 1.9:1 on my vy on Saturday and i am getting the same noise i am not very happy it sounds ****.

Have you noticed any gains though? Will you be keeping them or changing them back?

[MACE]

They are suppose to sound much like the factory item. If you guys are fairly confident that they been installed correctly we'll send you up a new set of rockers shortly along with new COMP reusable rocker bolts. All we need back your current high ratio rockers for analysis. If you have any questions or concerns please don't hesitate to ask.

Kindest Regards,
Steve

[OZ38]

I have a series 1 VY V6. The Mace rockers are reworked stock rockers although they came with pushrods. So they're not meant to sound like an old sewing machine then?

No they should be quiet in operation. Did they come with new rocker bolts & what torque did you do them up too ?
Maybe do a check of the torque on the bolts. Maybe later VY V6 series I are affected too.

I have fitted Yella Terra Ultralites in 1.9 : 1 to my series I VY & also a set of YT Ultralite 1.95/1.90 : 1 splits to son inlaws L67 (VS vintage engine) VR ute.
Both run very quiet.

Cheers

Deek

[mgrb1211]

No they should be quiet in operation. Did they come with new rocker bolts & what torque did you do them up too ?
Maybe do a check of the torque on the bolts. Maybe later VY V6 series I are affected too.

I have fitted Yella Terra Ultralites in 1.9 : 1 to my series I VY & also a set of YT Ultralite 1.95/1.90 : 1 splits to son inlaws L67 (VS vintage engine) VR ute.
Both run very quiet.

Cheers

Deek

I had the mechanics at UltraTune fit them. Steve from Mace has advised that he'll be sending a new set so I'll have them fitted as soon as I receive the new set. What torque would you recommend?

[mgrb1211]

They are suppose to sound much like the factory item. If you guys are fairly confident that they been installed correctly we'll send you up a new set of rockers shortly along with new COMP reusable rocker bolts. All we need back your current high ratio rockers for analysis. If you have any questions or concerns please don't hesitate to ask.

Kindest Regards,
Steve

Hi Steve

Thank you for your excellent after-sales service. I look forward to receiving the new set, and I'll send the 1st set back to you once the new ones are fitted. What torque would you recommed them set at?

Marco.

[OZ38]

I had the mechanics at UltraTune fit them. Steve from Mace has advised that he'll be sending a new set so I'll have them fitted as soon as I receive the new set. What torque would you recommend?

If they are the re-usable cap head bolts then torque them up to 25 foot pound.

Cheers

Deek

[aza03]

25 foot pound is too high they should be torqued to about 11ft.lb which is about 15NM

Steve said to me that 13-15NM is fine

[mgrb1211]

Thank you for the advise on the torque.

[ChargedAuto]

When I fitted the rockers to my second engine VY II, I had the same tapping noise, and I HAD the better push rods etc.

I had to remove the extra metal on the head castings. No a hard job and fixed the problem. I had to remove quite a bit of metal, but it shouldn't have been there in the first place. Just don't let any fall into the engine.

[VT-565]

Wow. 1.98:1 huh? that's up there. Are you using aftermarket valvesprings? You would be crazy not to with a ratio like that and especially having a roller ramp rate as high as it is too. Are the factory rockers roller tipped? From memory they're not. Would be interesting too to note the valve to piston clearance with the higher valve lift. Has anyone bothered with this yet?

[ChargedAuto]

I have since done the valve springs as well however they did work fine with the originals until pushing bigger power.

MACE now have rockers over 2:1 so I'm sure the clearances are fine and have been tested to ensure things are all good.

[VT-565]

I have since done the valve springs as well however they did work fine with the originals until pushing bigger power.

MACE now have rockers over 2:1 so I'm sure the clearances are fine and have been tested to ensure things are all good.

Can't understand why you would bother changing the rockers if you weren't chasing the bigger power figure? I'm just a firm believer in changing the springs to suit whatever it is you might be doing, everyone wants bigger revs, more power etc. but neglect this area sometimes which as you know, can have pretty bad consequences if valve control goes downhill.
Has anyone had any issues with lifters or cam integrity with these higher valvetrain loads?

[sp001in]

Cam intergrity..... 2:1 rockers = not great

[trentvy]

LMAO that shudnt be like that

[OZ38]

25 foot pound is too high they should be torqued to about 11ft.lb which is about 15NM

Steve said to me that 13-15NM is fine

You are wrong.

Torque settings for Stock Rocker bolts (which are torque to yield) are set at 15nm + 90° turn angle (metric setting), or 11ft/lb + 90° turn angle (imperial setting).

You have left off the 90° turn angle for torque to yield bolts which I'm sure he is not using, as Steve would have supplied re-usable Hi-tensile cap heads.

The re-usable cap heads from Yella Terra, ZZperformace & Intense-racing all state a torque setting of 25 ft/lb as these are not torque to yield setting bolts.

Now just think how much extra torque is applied to the stock bolts when the 90° turn angle is added after the 15nm or 11ft/lb ?



Stock cam lift is .258" times this by the rocker ratio used to get max valve lift.

0.258" x 1.98 rocker ratio = 511" approx.
0.258" x 2.01 rocker ratio = 519" approx.
Stock heads can support .520" lift max. but should still be checked for clearance between the retainers to valve stem seals.
Using milled retainers can gain you another 0.030"
Using Viton valve stem seals can gain you another 0.020"

Using aftermarket valve springs with set heights of 1.800" (stock springs are 1.720" set height) can also help but then coil bind heights need to be checked as well.

Cheers

Deek

[OZ38]

Cam intergrity..... 2:1 rockers = not great

Is there more Info on how that happened ?

Or how you think it might have happened ?

Cheers

Deek

[MACE]

If they are the re-usable cap head bolts then torque them up to 25 foot pound

Only very recently we’ve been supplying reusable rocker bolts with our rocker sets. The rocker bolt sets that both mgrb1211 and aza03 were supplied with were genuine GM torque to yield bolts. The new usable rocker bolts we now supply with our rockers, require 22-23 foot pounds of torque.

Wow. 1.98:1 huh? that's up there. Are you using aftermarket valvesprings? You would be crazy not to with a ratio like that and especially having a roller ramp rate as high as it is too. Are the factory rockers roller tipped? From memory they're not. Would be interesting too to note the valve to piston clearance with the higher valve lift. Has anyone
bothered with this yet?

Rockers of a similar ratio (1.97:1 or 1.98:1) have been in the market place for many years, with no issues (that I’m aware of). The only time a major issue will arise is if you use these ratio of rockers with the standard pushrods, only because of clearance issues between the pushrods and the cylinder head. It’s for this reason our 1.98:1 ratio kit comes with new pushrods standard.

Aftermarket valve springs are not required when used in NA or in low boost applications. It’s only when you cram a fair amount of boost into them that they really require stiffer springs for consistent operation, given the extra force acting on the valve due to the increase in inlet pressure. Which is completely understandable as even stock standard factory internal engines, subject to an increase in boost pressure (XR6 turbo, LS1), require stiffer valve springs.

Can't understand why you would bother changing the rockers if you weren't chasing the bigger power figure?

Going to stiffer valve springs, when not required, will rob you of horsepower.

Has anyone had any issues with lifters or cam integrity with these higher valvetrain loads?

Not that I’m aware of. Only when using standard push rods with anything above 1.97:1, as they may foul up against the cylinder head.

Cam intergrity..... 2:1 rockers = not great

Our 2.05:1 (not 2.1:1) ratio rockers are not available yet, so they certainly couldn’t have caused that. In regards to the integrity of the stock camshaft it’s certainly a lot better then people given them credit it for, which is why there any many reground factory camshafts successfully in use in conjunction with stiffer springs and higher ratio rockers etc. I even know of a few people who circuit race their V6 with reground cams, which are fine. Don’t get me wrong I would rather spend the little bit extra and go for a quality billet grind cam, given the superior metallurgy, however the factory item is still good.

As for why it failed given the fact that it’s a cast item, it may have had a void close to the surface causing a crack to propagate due to fatigue from that point. It’s not very common at all however even factory cast (mass manufactured) items can still have these problems, whether it be a conrod, crank, cam cylinder head etc. The only way to find this problem out from factory is to x-ray or magnaflux test cast components from factory. Unfortunately it would cost to much for a normal manufacturer to do, unless you’re Ferrari… Building a Ferrari 612 Scaglietti - Virtual Tour - Motor Trend (far bottom left)

Torque settings for Stock Rocker bolts (which are torque to yield) are set at 15nm + 90° turn angle (metric setting), or 11ft/lb + 90° turn angle (imperial setting).

This is more accurate. Though for the first stage you can torque them up anywhere between 11-19nm then for the second stage + 90°

Stock cam lift is .258" times this by the rocker ratio used to get max valve lift.
0.258" x 1.98 rocker ratio = 511" approx.
0.258" x 2.01 rocker ratio = 519" approx.
Stock heads can support .520" lift max. but should still be checked for clearance between the retainers to valve stem seals.
Using milled retainers can gain you another 0.030"
Using Viton valve stem seals can gain you another 0.020

The 2.05” will have around .529” of lift and will be supplied with new retainers. However we’re still doing more testing at the moment.

[OZ38]

The rocker bolt sets that both mgrb1211 and aza03 were supplied with were genuine GM torque to yield bolts.

So as I said earlier 15nm or 11ft/lb on its own without the turn angle applied would be the wrong torque.

This is more accurate. Though for the first stage you can torque them up anywhere between 11-19nm then for the second stage + 90°

Well if we are going to split hairs then... Straight out of the VT V6 GMH service manual.

"Rocker Arm Pedestal Bolts" ...11 - 19 Nm plus 87 - 93 degrees turn angle.

The 2.05” will have around .529” of lift and will be supplied with new retainers. However we’re still doing more testing at the moment.

Stock springs are set at 1.720" set height, even if the stock retainers were relieved to give more clearance to the valve stem seal you will still need to check for coil bind with .529" lift.

If modded retainers with a set height of 1.800" are used with stock springs then valve bounce at revs could be an issue. As the stock springs and retainers have a seat pressure of 70lb. When stock springs are used with a 1.800" set height the seat pressure will drop to about 55lb.

Zooomer at ZZp had his crew do some very good testing of all this.

Cheers

Deek

[sp001in]

Is there more Info on how that happened ?

Or how you think it might have happened ?

Cheers

Deek

Info..... well look this happened to the car on the hiway, went to overtake a caravan, put the foot to the floor gearbox drop back a gear, and the car just started back firing like someone firing a gun....

Pulled over, ripped the air pipe off the throttle body and, got the missus to crank the motor over, crank crank crank. BANG flames shooting out throttle body. NEVER A GOOD SIGN ON A FUEL INJECTED CAR.

called tow truck.

got it home, ripped tapper covers off and rotated motor by hand. watching the rockers as i did. 5 and 6 failed to move. pulled valley cover off, pulled heads off, and it just got worse.

anyway after pulling entire motor apart. pulled cam out to find this. in the sump was a a bent piece of metal from some where. MOTOR WAS ****ED. still sitting in spare block where i used to live.

anyway apparently it the rockers being non rollers, put to much pressure on the weakest part of the cam, and it just snapped. literally. twisted itself apart.

experience tells me that there must of been an oil flow related problem too. but anyway now I'm back to 1.8 rollers and have had no trouble and honestly not too much difference in power.

[sp001in]

Our 2.05:1 (not 2.1:1) ratio rockers are not available yet, so they certainly couldn’t have caused that. In regards to the integrity of the stock camshaft it’s certainly a lot better then people given them credit it for, which is why there any many reground factory camshafts successfully in use in conjunction with stiffer springs and higher ratio rockers etc. I even know of a few people who circuit race their V6 with reground cams, which are fine. Don’t get me wrong I would rather spend the little bit extra and go for a quality billet grind cam, given the superior metallurgy, however the factory item is still good.

thanks MACE, i was not using your rockers. Mine were from a weber racing in the usa.

but bear in mind like i said, I can't completely blame the rockers as I found a big piece of folded metal in the sump. just didn't trust them after that, and being as I only had them on the car 1 week prior to this I pointed directly to these.

I am interested in something higher ration again, as your company does sound very reputable