WhiteDiamond

Just a quick thought on the coolant issue. I believe the LS2 release info from GM indicated that the LS2 coolant pump is higher flow capacity than the previous pump. Does anyone have the specific detail on that?

Please keep us informed on the sleeve progress.

Todd

Steve - Race Eng

iTrader: (1)

The LS2 pump is a step backward not forward. To save a couple of pounds, GM reduced the bearing diameter from 1 1/2" down to 1 1/8". Instead of using roller bearings on a 3/4" shaft they now use a little ball bearing on a much smaller shaft.

Flow is not up to that of the LS1 pump either. They reduced the size of the thermostat housing and stat itself.

Evans pump with their 160 degree stat flows 85 gallons per minute.
LS1 pump with GM stat flows 55 gallons per minute.
LS2 pump with GM stat flows only 39 gallons per minute.

Evans worked with stats to get the flow higher on the LS2 but gave up. I was told they could not get a 160 degree stat to work reliably in this pump. They saw no reason to pursue it further and recommend using the LS1 pump instead.

Steve

DrkPhx

iTrader: (15)

Steve - Thanks for information on the water pump. That is good information to know.
Question; Is the Evans pump just as effective with standard Dex-Cool coolant or does it require the Evans coolant?

Steve - Race Eng

iTrader: (1)

The Evans pump will work fine with regular anti freeze - water mixture on a stock or dry sleeved block. It has much improved impeller design over the GM pump.

Steve

Richiec77

iTrader: (3)

Quick question. I know an LS2 kit is in developement.

I'm going to be needing a new engine in about a year and I'm always wondering about Sleeving and Daily Driving. Is it OK to Do?

Also, What is the Difference in Stregnth between the LS2 ans LS1. From what I read you were saying the LS1 is better? I have a '99. Is that the Later Block or a maybe year (in between)

I'm asking because I will probably still have my motor in place and then build a shortblock to replace it with. So I might start out with a different block.

Steve - Race Eng

iTrader: (1)

The LS1 block is the best block for wet sleeving by far. Much more strength because they lack the windows in the main bulk heads that the other LS blocks have. We will have an LS1 MID wet sleeve for bores up to 4.200" this summer.

The LS2 with dry sleeve will do the trick also. We will have a prototype done shortly for testing. For an engine that is not full bore, the LS2 dry sleeve sholuld work just fine. Price to machine and install sleeves will be considerably less than the wet sleeve. Of course you will most likely have to purchase a new block for the dry sleeves.

Steve

Boosted LS1

From what I can gather you need an ls1 block with the centre row of rocker cover bolts as opposed to the peripheral rocker cover bolts. So, you don't want a 98 block. The more common ls1 has the oil galleries joined together by a groove in the rear of the block, right under the rear cover. These are the only ls1 blocks I've seen. I think the early (98) block doesn't have the groove in the block, the groove is in the cover instead. Steve will probably clarify this for you.

Hope this is helps. Mike.

Steve - Race Eng

iTrader: (1)

Mike,

The earliest LS1 blocks did not have a cross over passage cast into the block between the lifter bores at the rear of the block. There is a cross over passage in the cover but it is rather narrow. There is sufficient material in the block to either machine or die grind a channel in the block. A bit more work but it can be done.

Steve

BOWTIE

Steve, this is a little off topic, but you sound like the one to answer this question. Do you really think GM introduced the cast in bulk head windows to improve performance or do you think they did it to reduce machining cost, and reduce the the amount of aluminum used in the block casting process (though the difference would be minute, with the number of blocks produced the savings would be measurable); then tried to sugar coat this with claims of increased performance due to improved breathing. I am asking because I have had this argument with numerous individuals over the last 3 to 4 years, to me it sounded like another case of the improved cooling heads of the early 80's.

Boosted LS1

Thanks for the reply Steve,

I also found a sand cast block which hasn't got the windows so some of those are usable as well. Probably from the Camaros.

Mike.

Steve - Race Eng

iTrader: (1)

Good question.

I believe the main reason is to cut weight and reduce manufacturing costs. I do however believe there may be a slight increase in power on a wet sump engine because of the deep skirt design of the block. Less if you use a vacuum pump, probably none on a dry sump. Even if there were a good kick out style aftermarket pan, it wouldn't do much good on a deep skirt block. A deeper pan would be good but there just isn't any ground clearance.

Some have claimed fifty horsepower increase with the windowed blocks. Seems a bit much to me. If that were the case, all the Bow Tie racing blocks would surely be cast with holes in the main webbing. I'm not about to start cutting holes in the main webs to increase power on any of the stuff I build!

Steve

BOWTIE

If someone claimed they made 50 more hp with an identical setup with the windowed block, I would ask them what they had been smoking; and then I would only believe it if they did it right there in front of me ( I am talking the machine work, assembly, and testing). I just can not see how the LS1 needs that much breathing capacity anyway. After all, for every piston moving down displacing air, the piston directly across from it is moving up creating a low pressure area for that air to travel to. There is no obstructon or bulk head between the two opposing cylinders. Therefore, it seems to me that the only byproduct that would need to be moved through the bulkheads would be what combustion gasses escape past the piston and ring package. In my opinion, if you need windows in your bulkheads to evacuate that much blow by you have much greater problems than your block selection. Not only that, but if the windos are needed for that much breathing, it would seem that our PCV systems are entirely too inadequate. I still think those that claim a 50 hp increase read one of GM's sales pitches and bought it hook, line, and sinker. I remember when I first heard about the new windowed LS6 blocks... I had flashbacks of all the old Oldsmobile motors I built in the past. Huh.