SEARAYH20-ski

THANKS 4 sharing INFO
TX might be alittle far away right now..OR a Good excuss to vist realatives lol
Above my tech experience. Like bullet proof

leaftye

Can't you retap the holes yourself? I could swear Wheel2Wheel had an example of that in Handzels book.

Wnts2Go10O

iTrader: (12)

its not a big bore but someone has already built a 454ls motor ill take 2 please. what?...theyre SMALL blocks...

Cal

iTrader: (1)

ROFL!

BTL FED

iTrader: (9)

Its not something you would want to do by hand, they use all there fancy machinary to do them

Boosted LS1

I wish I could afford a C5 block! I certainly wanted one. They are the mutz for high rpm endurance events but I couldn't afford to damage a liner if I got a major detonation spike. Because I'm not sustaining high rpm's for very long, durability isn't my concern. What worries me is a split liner or something equally bad happening within a cylinder which could scrap the block. So for my application I shall use a darton block because I can replace the liner. I'm very impressed with the C5r specs though and it's ideal for some people.

Mike

sb427f-car

Big bore, tall deck, iron and or aluminum would be great. With both materials being used, it will trickle down to the end users as a cheaper cost. Also, with muliple manufactures and similar products, we should be getting better prices. It's a good time to be Gen III enthusiats. "Things are about to get even more interesting."

XLR8NSS

iTrader: (4)

Hey Nicky

Why stop at the 4.155" bore? Don't some standard SBC bowtie blocks go out to 4.185"? That and a 4.125" crank would make some pretty mean 454ci LS small blocks.

ALOT of nostalgia in that number.

Steve - Race Eng

iTrader: (1)

Nicky,

What I would like to see from GM is a race quality block that has priority main oiling and larger diameter head fasteners (or perhaps more) , and larger main fasteners. Both in aluminum and iron. A tall deck version allowing longer strokes would be a welcome addition as well.

I believe you were refering to one of my posts regarding strength of MID sleeves. The material specifications and quality control for the C5R castings are impressive. The C5R aluminum cylinder walls and material used to make the iron liners however are no where near as strong as the material used to make the MID wet sleeve.
I have always stated that the MID cylinder was superior to anything on the market and I will stick by it. I do not work for Darton by the way but am closely associated with them.

You may not realize that Darton makes sleeves for the vast majority of Top Fuel and Funny car teams. They also make both wet and dry liners for many tractor puller diesels. A top fuel engine produces in excess of seven thousand horsepower. The supercharger on top of the engine provides over fifty pounds of boost. Peak cylinder pressures are upwards of 15,000 pounds per square inch. Cylinder pressure info comes from Austin Coil. A diesel tractor puller engine runs upwards of 100 pounds of boost. I do not have peak cylinder pressures for these engines, but the numbers must be impressive. Darton also supplies replacement liners to several cup teams but the power these engines produce pales in comparison to the ones above.

The MID sleeves and in fact every sleeve Darton makes is made out of the exact same material as their top fuel line of sleeves. This material is centrifigally cast ductile iron. The grade is based on a highly modified 100-70-03 ductile iron. The 100 stands for 100,000 psi tensile strength minimum, the 70 stands for 70,000 psi yield strength, the 03 is a measure of elongation (ductility). Now, the alloy used by Darton is considerably stronger and more ductile than 100-70-03. Tested tensile of the Darton material is between 110,000 psi and 130,000 psi tensile strength. Darton specifies an elongation of not less than 5% but most tested sleeves come in at near 9%. They have put some thin wall replacement style liners in a press and pushed the liners oval without breaking. They usually have one on display at PRI. Try that test with one of your "special" material liners and see what happens.

The C5R liners are .060" thick centrifigally cast gray iron (roughly 50,000 psi tensile) backed by 34,000 psi (at the very best) 356T6 aluminum alloy parent block material. Darton makes a replacement liner for the C5R by the way. The MID sleeve is over .200" thick (120,000 psi average tensile strength) at the thinnist point @ 4.160" bore. Even if the C5R liner were made out of Darton ductile iron, there is no possible way the liner and aluminum wall could be as strong. It does not take a rocket scientist to see that.

If people were driving over their crankshafts, I would say there is a structural problem with the standard production blocks or modified with MID sleeve blocks. I have not heard of this happening however. I believe that GM does an excellent job of casting the stock blocks from 319 T6 aluminum which is just about as strong (31,000 psi) as 356 T6. It is however not as ductile.

Another thing I should add is we went to great lengths in the design of the MID sleeve to provide for much improved cooling than on the siamesed bore castings. There are several coolant slots milled between the siamesed walls of the MID sleeves to prevent hot spots. This in combination with the patented coolant groove and transfer holes in the sleeve flange area greatly reduce the chances of detonation related engine failures.

In any event, we are all on the same side here. We love cars that go fast and do our best to find ways to make them better and faster.

Off topic a bit but when do you anticipate the release of the LS7 head castings? I have many people asking even from over seas.

Sincerely,

Steve Demirjian

parts@sdpc

Thanks for the input on your request for a GM Performance heavy duty block. I need all the input we can muster-up here ---- GM reads these threads!!!!!!!!!

Like I said, you get what you pay for! I clearly stated that the MID block has its place in the economy of the business. GM Racing tried a similar version to this system and they experienced problems, I did not say that it had anything to do with the strength of the sleeves. Again, I stand by the statement that the overall integrity, machining, and material of the LS1 MID block is not the equivalent of the C5R block. I want people to know the facts about the C5R block. Maybe you misunderstood me?

And yes, I am very familiar with Darton and NHRA racing. Some of my best friends have been long time crew members on Top Fuel teams. I was using Darton sleeves in the 1980’s to build “sleeved 396” blocks to run in Stock and Super Stock. I have probably attended or participated in more than 250 NHRA national and divisional events. I do not claim to be a rocket scientist and I certainly do not have all the answers, but I do have a degree in engineering and lots of “hard luck” experience in the engine department that has made me a little wiser today and I am always willing to learn more!
Any comparison statements I made, I have tried to back with the facts, and I clearly stated that it was made “IMHO”.

Like I said, I want a less expensive big bore block! And I believe that we will have some options here in the near future that will cost less than a fully machined LS1 MID sleeved block, IMHO!
Steve, out of curiosity why have you requested larger diameter main bolts?

On the topic of LS7 heads – I have some and they are bad ***! Corporate management has said that the LS7 parts can not be released until the car is released to dealers. So that tells me somewhere between July 30th and September 15th, we will all have to wait and see. I have worked diligently with GM Performance to try and have the parts on the shelf for immediate availability and that looks very promising!

sb427f-car

That is great to hear. Just how bad *** are they so far? Have you gotten a chance to run numbers on them or are you not allowed to say? They going to be competative with the current aftermarkets in terms of $$$$? Thanks Nicky.

parts@sdpc

I hope to have an engine on the dyno next month
Flow numbers look very promising, 330-plus @ 0.550" and over 350cfm as the valve passes 0.600" lift. Approximately a 280cc intake runner volume.

XLR8NSS

iTrader: (4)

Back on the topic of the Iron Bowtie blocks.

When will you be talking to GM about these and IF they decided to make one realistically how long would it be before we saw them?

4.185" capable and available in standard or tall deck.

parts@sdpc

I am in continuous contact with those who are looking into this project, but more importantly they (GM) are reading threads like this to see the interest!
There is a business case on the planner right now. If they believe in the value and we can show the interest, then I would say 6-months (from the date of approval) until we see a block.

69firebird

iTrader: (14)

Id be down for one of those blocks.

also what is the cost on the LS7 heads?
and will they work with the standard intakes we currently have
ed

427

iTrader: (3)

I would order a couple at the start for sure. Fixing the oiling system would be a big help.Moving the main oil galley so I could run bigger lifters would be great. Making the deck water jacket holes about 10 times smaller would be great also.


Kurt

XLR8NSS

iTrader: (4)

FACTORY BIG BORE BOWTIE BLOCKS for ~$1400-1800!!!!

Come on people show some interest.

blackz93

iTrader: (2)

i dont think 500 ci will be too far away!

DAPSUPRSLO

iTrader: (14)

Not to nitpick but I was told the intake was 264cc and the exhaust was 87 cc. This is right from one of the GM Engineers at the c5/c6/c6 z06 unvailing bash at Bowling Green Kentucky. I asked the question during the seminar that was given regarding the ls7 engine. The information was not provided right away but given via voice mail at a later date. Just an FYI.

Steve - Race Eng

iTrader: (1)

Regarding the bottom end bolts. As the engines get larger and larger combined with nitrous and or blowers stronger fasteners will be required. Larger diameter fasteners are less expensive than the high strength alloy option on the smaller fasteners. I have a buddy in town that is putting 6-71 blowers on these engines now.

You might want to give some thought to a non deep skirt race block similar to the small and big blocks. That would allow kick out style oil pans. Again, larger fasteners would regain some of the bottom end strength lost in the non deep skirt style block.

Question on the LS7 heads. I'm a bit curious about the use of titanium intake valves on a street engine. What is being done to the valve seat and valve face to get the valve to last a reasonable time?

Steve