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Discussion Starter · #1 ·
I am thinking about doing the roller rocker upgrade in lieu of doing a cam change. Has anyone had any experience with this company out of Australia, and does anyone think that the 1.9 roller rocker ratio is too high and will cause valve guide wear, premature parts failure, etc. vs. the standard 1.85?
 

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Plenty of guys are running 1.85 RRs. I doubt that the extra .05 is going to make much difference as long as you have the correct length pushrods. Haven't heard of anyone using Mace before.
 

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The difference is the final lift .514 for 1.85 to .525 for 1.9.
Any one that modded 3800 V6's knows about modded rockers. They all come from Austrailia. They have been doing it for 15 years. Now they are doing the same process for the V8 rockers. The best part is that new pushrods are not required. The pushrod seat is moved in but at the same height as stock. They are also warranty "friendly". You won't notice the difference visually. I emailed Mace a while back. Sold my winter beater the other day. Once it and the extra parts goes, I will order a set.
The lift would be equal with the LS2 cam, so there would be the exact same valve guide loads as an LS2 engine. As for valve springs, the GMPP catalog lists our springs good for .530" lift. So if you keep to the stock red line you are ok.
 

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:thumbsup: This sounds good keep us updated. Good luck.
 

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What kind of price are you looking at for the rockers.

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Discussion Starter · #7 ·
Mace rockers

A couple of points on increasing the rocker ratio:

1. I believe, from what I've been reading, that increasing the ratio by essentially 11.7% will require a spring that will be able to handle the extra speed of the lift. Remember, the large and heavy intake valve is going to be jerked around at a faster rate up and down and up to, presumably, higher RPM's due to the higher lift that shoud extend the cam's range. So, higher RPM, faster movement rate, and heavy intake valve lead me to think that the LS3/LS9 spring is a good minimum piece of insurance for $70. I think the PAC 1215 spring is probably the best bet, but not sure how the 115 lbs on the seat will effect the DOD lifters. Anyway, you might be safe with the stock springs but I bet that they poop out early at higher RPM's.

2. I wasn't aware that we could use the stock pushrods, I thought the 7.45" were required. That is good news. How do they achieve the extra lift without changing the geometry at the pushrod? But if that is true, fantastic.

3. The price on the Mace website was $396 Australian dollars. The $US and $AU dollar are nearly 1:1 right now so that is good news. Actually $1 US buys $1.02 AU.
 

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The additional lift is acheived by relocating the pushrod cup closer to the pivot. The pivot to valve is not altered. The acceleration of the valve is faster than the stock cam, but no faster than the LS2 cam that acheives similar lift in similar duration. The points you bring up are valid on more radical cams. Our stock cam is so weak, it only brings it up to older stock cams.
 

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Are you kidding? If these are going to blow up at .525". Then anybody with a cam that has lift higher is driving a time bomb. A 1C cam with .600 lift on stock arms has way more stress. These modded rockers are new to the LS group. They are old new to the 3800 V6 crowd. Basicly you get an LS2 cam with just a rocker arm change.
 

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I've been wanting to do rockers for a while, then a dod cam down the road.
How would this affect cam choice etc?
Shaun

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For your situation Shaun, it's all or nothing. Our stock cam is so small, 1.9's bring it up to normal. Now if you put 1.9's on a normal .550 lift cam it would equal .616". A huge difference. Stock rockers are not designed to accept that much. If you are going to DOD delete, I would not suggest doing the 1.9 rockers as a middle step. Why buy a cam and rockers when you can get the results from the cam only. 1.9 are for use on the stock cam. 1.9's are to maximise the lift from the stock cam and not have to go inside.
 

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Anyone know if new pushrods are needed with these mace 1.9 rockers? Anyone running these rockers with good results?
 

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rockers :)


I remember doing these on my old Grand Prix GT 1.80 on the exhaust side, 1.85 on the intake side, and modded stock rockers 1.90 on my GTP


good times.
 

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Think I am going to get these rockers, LS6 beehive springs, and Comp 7.450 pushrods.
 

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The 7.450 are for Yella Terra rockers only.
 

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What size for these than?
 

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Best thing to do is use a push rod checker. I have one you can borrow. You pay shipping. Shoot me a pm if you want to use it.
 
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