vettenuts

iTrader: (4)

Did you order the Mantons?

ZeeOSix

Yes ... guess I forgot to specifically say that in my last post. Should have them by mid-next week. They'll probably make them tomorrow he said.

These seem to be very nice pushrods ... and the price isn't much more than any other chrome-moly aftermarket pushrod.

The tricky part was trying to determine the exact length I needed in the Matson based on the way they measure the pushrod length ...ie, flat-to-flat instead of "gauge length" like Comp Cams.

As I said earlier, it turned out that 7.400" flat-to-flat is about as close as you'll get to matching the OEM LS6 pushrod length because the Matson and OEM both basically have the same ball end flat diameter (within < 0.005") to measure from.

vettenuts

iTrader: (4)

Let us know how it turns out. Not sure why more don't use his pushrods, the price isn't that much more (if at all), the parts are very high quality and he turns them around very quickly.

ZeeOSix

Will do ... I'll take some photos of the OEM and Manton side-by-side when they show up.

You're right ... after checking out the Manton pushrods they seemed far supirior to the Comp Cam pushrods. The Mantons are thicker tube OD and thicker wall (I went overkill ), and they have CNC machined tool steel ball ends instead of the ends being formed from the tube material. Mantons supplies pushrods to many major professional racers, so they have a good reputation.

See attached sketch showing the measurements I got on the OEM LS6 pushrods out of my 2002 Z06.

vettenuts

iTrader: (4)

Your measurements are well within the tolerance of what I measured. Good luck with the install, waiting to hear how it goes.

Make sure you clean them good. I also soak mine in oil then put one finger over the end so they don't drain while installing. I also use Redline Assembly Lube on the rocker ball and valve stem to prevent a dry start.

ZeeOSix

Thanks for the tips ... I like the "finger over the end so they don't drain" tip ... never thought of that. While cleaning them, I'm going to spray some carb cleaner through the tube and blow them out with compress air, then oil them up. I do have some engine assy lube, so planned on using that too. Thanks for all your help vettenuts.

So in summary, my valve train upgrade from stock will be:

1) Manton 11/32" x 0.120" wall chrome-moly pushrods.
2) Comp Cams rocker arm trunion & bearing upgrade kit.
3) PAC 1518 valve springs.
4) New valve guide seals (OEM).

I originally wanted to just replace the valve springs due to the OEM failure rate, and of course once I got in there then all this other stuff got added on. This should make it plenty reliable over stock for not a lot of money in all the parts.

ZeeOSix

Got my Manton pushrods today. Did measurements on 1 of the 16 and all looks perfect. They also roll much truer than the stock pushrods. See attached photos for some pushrod candy.

Chrome Moly, 11/32" dia with 0.120" wall. 7.400" flat to flat. Flat is ~0.112" diameter, which is within 0.002 - 0.003" of flat on OEM pushrod. So Manton's will be within 0.001 - 0.002" of OEM gauge length.

Shouldn't have to worry about bending/flexing pushrods now.

ctd

iTrader: (1)

Good thread. I'm replacing my cam very soon & had the push rods on the radar....this makes it easy!

vettenuts

iTrader: (4)

Glad you are happy with them, how does it run?

ZeeOSix

Not all back together yet ... I'm slow. Also doing the rocker arm upgrade and valve springs.

crainholio

iTrader: (2)

Those look great, but why the different ID oil passages? Which side does the larger diameter go on, lifter or pushrod?

ZeeOSix

The photo shows a new Manton pushrod on the left, and the OEM pushrod on the right. The Manton pushrods do have a smaller oil hole ... ~0.070" is what I measured. The OEM pushrods have a 0.100" oil hole. The Manton rod has the same sized oil hole on both ends.

I asked the guy at Manton why the smaller oiling hole, and he said because at high RPM the OEM pushrods pump too much oil to the top end. He also said another reason for the smaller hole is to give more material depth near the area on the ball where the contact is between the ball and rocker arm pocket.

I doubt the oil volume will be restricted enough to cause any lubrication issues in the valve train. It will be interesting to see if my oil pressure increases or not due to smaller holes in the pushrods. I have lots of oil pressure vs. oil temp data to verify this after I get the car running again.

1Topgun

iTrader: (4)

I've been following this thread for a few days... very interesting information. One question though, how much does the Manton pushrod weigh, as well as the stocker, for comparison? Since overall valve train mass will affect performance at the higher rpm range, it would be another piece of data to work with. Good read...

ZeeOSix

Good question. I don't have an accurate scale, but the one I did use showed the OEM puhsrods to weigh ~60 grams and the Mantons I got weigh ~80 grams.

If I would have gotten the 5/16" dia rods with 0.083" wall they probably would have been a lot closer. I got the 11/32" dia rods with 0.120" wall ... that's where the added weight comes from, but also a lot of added strength. I doubt I'll be able to tell any difference in the way it runs from the added weight.

See page 3 if the Manton catalog that talks about pushrod weight.
http://www.mantonpushrods.com/Images/Manton_Catalog.pdf

Quote from the catalog:
"Do not be over concerned about pushrod weight. The difference between a stock 5/16 diameter pushrod in a small block Chevrolet and a 7/16 to 3/8 tapered pushrod, represents a difference of approximately 2.5% of effective weight. This is because the pushrod is on the slow moving side of the valve train. The effective increase in weight between the two pushrods may be small but provides a huge increase in valve train stability. Remember the valve side of this valve train is the critical side where any weight savings will make marked improvements."

vettenuts

iTrader: (4)

Its on the lifter side of the valve train so the mass is much less of an issue. The trade-off is stiffness vs. mass and stiffness is more important (within reason). The 3/8 double taper that I run are much heavier than these and there were no issues, as a matter of fact the power increased in the high RPM due to the stiffness increase.