Lifter mod FYI

[geldartb]

No, shipping to canada has gone up quite a bit unless its the small flat rate box and 4 pounds or less.

damn i was gonna say i shipped 6 3400 pistons across the country for like 20 bucks. but this was also 3yrs ago.

kinda sucks seems like all these foreign countries get boned on import charges and whatever they feel like tacking on.

[SappySE107]

USPS doesn't add brokerage fees but it still costs more than domestic shipping. Interesting note, while shipping to switzerland costs more than canada, they get their parts faster.

/thread crapping:P

[Keoki1978]

Its been since July that this disscusion was going on. Just wondering if any good news came out if moding the springs in our lifters will produce some good results. Ive been trying to get some low down on hyd lifters, but not much in the way of exotic race stuff. Nothings available...

Mine seems fine hitting 7100 with some 20W-50 oil. Cast crank probably wont handle much higher anyway...

Video coming soon.......

[gectek]

would def DEF not run 20-50 in anything but a motorcycle or a tractor. lol. it would act as a HP depleter at higher rpm IMO and wont wick away heat as fast

[Keoki1978]

I did the break in with Royal Purple Break-in Oil for the first 200 miles, either I didnt purge the coolant enough or not cooling enough that the engine is tipping the 210-220 scale. Got a 180 stat in. So, since I'm in a 95 degree climate, it was recommended to use a 20-50W oil.

[AaronGTR]

I live in Tampa too and I don't run oil that thick. It's overkill. Not only may it sap some HP but if it doesn't thin out enough it may not be lubricating as well as it should.

It's a little more complicated, but the general rule is the two numbers are oil viscosity at low and high temperatures, ie cold engine at start and engine warmed up. If you lived in northern Canada or Alaska, you might consider switching to a 0W-30 or 0W-40. The factory recommended 5W-30 will work for 95% of North American climates. If you were running a high HP engine that makes a lot of heat and you needed extra protection, then you might want to try a 5W-40, or a 10W-30 or 10W-40 if you live somewhere like Arizona or Mexico and regularly see 100+ degree outside temps.


PS. I am also curious though about the LS spring mod on the lifters and if there was any definite evidence/info found saying it would be beneficial.

[robertisaar]

actually car craft just did a test of a bunch of oil viscosities and the heavier oils had some scary numbers compared to like 0-20W synthetics

this was done with different oil weights and different pump volumes as well...

i'll see if i can find the article online.

EDIT: here it is... its so much easier to read in magazine form...

http://www.carcraft.com/techarticles/ccrp_0911_small_block_chevy_oil_pumps/index.html

/hijack

[SappySE107]

The lifters can take 7k but it depends on the cam profile as well. Mild ramp up rates (most regrinds/cams) don't stress the lifters much. Using the XFI hydraulic roller lobes or a more aggressive solid roller setup will certain lower the limits of the lifter, since the valve spring rate will be much higher. Stiffer internal springs are used to help the checkball operate properly at higher RPM but I couldn't show you a graph of where these would benefit over stock internal springs vs rpm vs valve spring load.

[3400-95-Modified]

I did the mod and I haven't noticed any improvement over what I had, YET I did add in those huge rotors up front so that in turn slowed my car down, so I have no real comparison to what it was like before since I was running stockers up to 6750 and it was still pulling. I have no lifter tick with my cam, like I thought I did before, (ended up being the chain for the most part though) so I really can't say.

Bottom line, they work and they are a stiffer spring, and it doesn't keep the valve open so I can only assume they would be able to take more abuse and hold up to more aggressive cam profiles like Ben is describing.

[RedBird]

kinda hard for me to say for sure, since my setup is completely different than before, but i put in my modded lifters when i swapped motors again, and it sounds a whole lot healthier than my 3400 did, plus i go right to my 7k limiter almost every day and haven't had a problem for 3 months now. it makes power right through and has plenty of idle vacuum, etc. i know Dave noticed a big diff in his idle vacuum when he did the mod.

[AaronGTR]

Well the springs are designed for LS1 engines so... if you were using valve springs that were stiffer than LS1 springs, and a cam that was more aggressive than an LS1 cam... would it be safe to assume then that these springs would be at least "safe" to use and possibly beneficial? Does it depend more on the ramp rate of the cam lobes rather than the lift, or is it more about the RPM you are running it to, or a combination?

For example I don't ever plan on running my motor to 7000rpm. The trans won't shift at that speed and I have a stock rotating assembly. My redline is set at 6300 and I don't plan on going over that. I may be changing my cam eventually to one with a little more lift but less duration than the one I have now. Would there be any point to doing that lifter mod?

[AaronGTR]

actually car craft just did a test of a bunch of oil viscosities and the heavier oils had some scary numbers compared to like 0-20W synthetics

this was done with different oil weights and different pump volumes as well...

i'll see if i can find the article online.

EDIT: here it is... its so much easier to read in magazine form...

http://www.carcraft.com/techarticles/ccrp_0911_small_block_chevy_oil_pumps/index.html

/hijack

Definitely an interesting article, but I'm not sure how much you can correlate their info to application on our engines. They were using a different engine with different oil pumps and their average and peak oil pressures even with the stock pump are much higher than our stock pressure. We don't know what temps they were measuring at either which is a very important factor.

The most useful info in there is the correlation between oil weight and flow, and the assertation that flow is more important than pressure. I remember reading a few stories here about people who used the high volume oil pump from GMPP with disastrous results. I wonder what kind of oil they were using though? Putting in a high volume pump with stock weight oil would result more pressure but less flow. I wonder if one of those pumps might work better with some 5W20 or 0W20 oil? Of course it still wouldn't really be needed unless you were building a race engine for a circle track car that was going to be running at 7000+ rpm non stop.

For a street car I'd just stick with the stock pump and oil weight, and only tailor the oil weight if you live in a climate extreme. It's a little hard to duplicate the amount of engineering and testing GM did when they picked that pump and oil.

[robertisaar]

Definitely an interesting article, but I'm not sure how much you can correlate their info to application on our engines. They were using a different engine with different oil pumps and their average and peak oil pressures even with the stock pump are much higher than our stock pressure. We don't know what temps they were measuring at either which is a very important factor.

The most useful info in there is the correlation between oil weight and flow, and the assertation that flow is more important than pressure. I remember reading a few stories here about people who used the high volume oil pump from GMPP with disastrous results. I wonder what kind of oil they were using though? Putting in a high volume pump with stock weight oil would result more pressure but less flow. I wonder if one of those pumps might work better with some 5W20 or 0W20 oil? Of course it still wouldn't really be needed unless you were building a race engine for a circle track car that was going to be running at 7000+ rpm non stop.

For a street car I'd just stick with the stock pump and oil weight, and only tailor the oil weight if you live in a climate extreme. It's a little hard to duplicate the amount of engineering and testing GM did when they picked that pump and oil.

exactly. unfortunately the online article didn't include the table showing the final results. luckily, my loving wife bought me a subscription a while ago...

i'm going to try to recreate the chart here:

pump comaro

.....................Peak HP...Avg HP...Avg Pressure...Avg Flow(GPM)...Peak Temp
standard pump.....485.......391.6..........50.3............ ....6.0..............160
high volume.........477.......386.9..........64.2...... ..........6.2..............160
high pressure.......481.......389.7..........65.6...... ..........6.1..............160
big block.............480.......387.5..........68.0... .............6.3..............160

viscosity comparo

.............Peak HP...Avg HP...Avg Pressure...Avg Flow(GPM)...Peak Temp
30W..........475.......383.9..........67.1........ ........6.1................162
20W-50.....477.......387.0..........67.4.............. ..6.5................163
5W-20.......479.......386.3..........59.4............ ....7.2................166
0W-20.......478.......387.5..........59.7............ ....7.4................166
0W-10.......480.......387.4..........55.7............ ....7.4................165

take it for what its worth...

[AaronGTR]

Wow, those are some pretty low temps they were testing at. Of course, I've heard older style V8's tend to run at lower coolant and oil temps than newer engines. I thought they recommended 180 degrees or higher as optimum for most oils these days though. I know I see 195 regularly on mine once it's fully warmed, and most bypass thermostats for oil coolers are in the 180-195 range. Would have been nice if they had tested a more common 5W30 or 10W30 too. Oh well, it's still interesting info.