Roller Roker Arms

[pirate]

I have a chance to purchase some Comp Cams #249-1413-12, Magnum Roller Rocker Arms, For Chevy 60° 173 V6, 10mm rocker stud, 1.52 ratio for a very good price. Will these work on my 3.4 GM Crate Engine with cam as supplied?
Is there a real advantage and is it a worth while thing to do. Understand about the less friction possibly a few more RPMs. Will it add any measurable horsepower?

Main question is will they work inthis engine?

[bob442]

stock ratio is 1.6 and 1999+ is already a roller. roller tip is a different question.

[pirate]

Should have clarified these are roller tip.

[SappySE107]

3.4 Crate is an iron head gen 1 motor, so those would be 1.5:1 stock. Higher ratio would make more difference. There might be a small increase in power from the stiffer rockers and more consistant ratios from rocker to rocker compared to stamped rockers.

[neo71665]

They will work, I have the 1.6 ones on my 3.4

[Classick Century Custom]

Let me ask that same question?, I have a 3100 W-Body Buick Century Custom.

[SappySE107]

Let me ask that same question?, I have a 3100 W-Body Buick Century Custom.

Nope, you have roller fulcrum 1.6:1 rockers, so that is a downgrade.

[geoffinbc]

If you can get the 1.6:1 Magnum rockers instead of the 1.52:1's then do it. Brand new they are under $150 for the set.

[blownarrow]

I have a set of ProComp 1.6 full roller for your 3100, I'll give you for $120

[Classick Century Custom]

So in other words Ben I already have what most or some buy as an upgrade yet my motor came with them?.... as said in cam selection thread I am goin 30 over high compression so that being said I should go for the 1.8 rockers? or would you suggest something other then that.

[bszopi]

Until Scorpion comes out with their rockers, your only choice right now is 1.6 ratio. There is no higher ratio that fits these engines.

[60dgrzbelow0]

If your project involves the GM 3.4L HT Crate Engine... While you have the tin off the Iron Heads... consider these additions as helpful to the cause as well: (See attached images)

Your Crate Engine set up sheet will have a caveat about pre-oiling that motor before it turns even one RPM. With a 40% chance of destroying that engine upon start up in its history, they finally figured out that all the oil in their crate engines was settling out during train and truck transports to their final destinations leaving the oil pump, oil galleries and bearing surfaces bone dry. So trust me with this reminder...They mean it. When you prime that motor... It would be a good idea to use a good non-synthetic break-in engine oil like Royal Purple Engine Break-In Oil or Valvoline Racing Oil (with plenty of ZDDP) and a can of GM EOS (Engine Oil Supplement) in that motor along with a high quality Oil Filter, too. When you first start that engine... keep your RPM between 1,500 to 2,000 RPM for at least 25 minutes...without letting the motor idle...and you will properly condition the camshaft lobes with exposure to ZDDP and prevent unintentionally wiping the lobes off the cam. Afterward... shut the engine down...change the oil and oil filter using the same kinds of oil/supplements/filter and drive the car around at normal speeds not exceeding 45 MPH ...gradually accelerate and decelerate for about thirty minutes or so and give the engine parts a chance to comfortably break in. Keep using the engine oils as described above and change the oil once again at 500 miles and later at 1,500 miles... switching to a good synthetic like Mobil 1... otherwise...if you keep using engine oils with a high concentration of ZDDP...your CAT Converter Platinum Screen and O2 Sensors will become coated with Zinc and be useless. Best of Luck with Your Build!

Here is some information on a New Engine Pre-Oiler Tool I designed for the GM V-6 engines that you can make yourself:

http://s557.photobucket.com/albums/ss19/60dgrzbelow0/ANEWV6OILPUMPRIMINGTOOL/

For more tear down and build images on this very engine, please visit my photobucket for parts/pieces and part number images.

http://s557.photobucket.com/home/60dgrzbelow0/allalbums

[geoffinbc]

switching to a good synthetic like Mobil 1... otherwise...if you keep using engine oils with a high concentration of ZDDP...your CAT Converter Platinum Screen and O2 Sensors will become coated with Zinc and be useless.

Actually COMP cams is recommending its break in additive be added on every oil change. To prevent wear on flat tappet cams. So I am doing just that on my engine. The only way you would shorten the life of your cat or O2 sensors is if you burn a lot of oil.

However I have considered contacting Red Line Oil to see if their oil alone is sufficient for flat tappet cams.

[robertisaar]

actually, when a cat heats up enough, it DOES burn off the zinc contamination.

[sprucegagt]

Actually COMP cams is recommending its break in additive be added on every oil change. To prevent wear on flat tappet cams. So I am doing just that on my engine. The only way you would shorten the life of your cat or O2 sensors is if you burn a lot of oil.

However I have considered contacting Red Line Oil to see if their oil alone is sufficient for flat tappet cams.

Rotella T is also a good alternative. Walmart has it here in gallon jugs.