[Old Goat]

Make room for the new 427 cubic inch LS-7 being readied for the Corvette according to GM High Tech Performance magazine, July issue. They have the story. I snaggled the pictures I don't remember where, but about a month ago. I held onto them as a WTF?

 

[1COOLPC]

My goodness, I think I have eye damage from the strain of them trying to pop out of my head.

So this motor is likely dimensionally similar to the LS1 blocks and can possibly fit in most LS1 equipped vehicles.

3 valves off one cam, neat!

 

[GTOJ]

That is interesting how they set up the 3 valves.

 

[gto_in_nc]

Thank,s OG! Saw that little write-up in GMHTP last night but really like the pictures...

 

[Old Goat]

Ls-7

It is said to fit wherever a reular LS1 or LS6 will....Wahoo!

 

[GMH GTO]

So that was a gen IV V8? LS2 being the base motor and that was a 427 cubed LS7 as opposed to the LS6??? wow GM is gonna have alot of anticpated introductions this september.

I think gen IV V8, 3 valves and two camshafts in block, the exaust cam has variable duration and displacement on demand. Still I like the GEN III RPO LS1.

 

[mmciau]

Old Goat,

The two Monaro that race in australia are 7 litre (427 ci) and I think they are Gen III that have been sleeved and stroked.

Mike

The photo I have attached is from the galleries of Garry Rogers Motorsport based in Australia.

 

[CMNTMXR57]

We've seen those pics before I thought though. I distinctly remember the three valve arrangement.

 

[Old Goat]

3 valve

We've seen those pics before I thought though. I distinctly remember the three valve arrangement.

Agreed. I wish I could remember where I got them... The article speaks to the 3 valve arrangement, but not how it's done on the cam end. I ran out to the 'shop' room and grabbed an old 098 Duntov cam. I don't think even that longer cam has room for 8 extra lobes even allowing for narrower rollers and lobe spacing, making a two 'cam-in-block' motor a possibilty. I wondered how long this would take to surface once I saw the V6's and such with balance shafts in the block over the cam to smooth them out. Simply go back to the V8 design and crank counterweight balancing and add the second cam. I guess the next questions go to why? Why not 4 valves, and why not DOHC with rocker? Surely the engineering of placing the cams at the valve would be cheaper and easier eliminating push rods, and DOD could move from the lifter to the rocker?

 

[flyinlow]

Here's how they do it.

http://www.ai-online.com/issues/article_detail.asp?id=254

 

[GMH GTO]

Old Goat,

The two Monaro that race in australia are 7 litre (427 ci) and I think they are Gen III that have been sleeved and stroked.

Mike

The photo I have attached is from the galleries of Garry Rogers Motorsport based in Australia.

That 7 litre is the same as the C5R vette and many drag cars. It would be very easy for GM to design the block at this point to have 4.125" bores and have proper sleeves. Would be a great marketing tool too.

 

[White Rider]

xcuse my ignorance but this seems like a complicated design, the 3rd valve apparently having 2 pushrods... how is it anymore "reliable" or better or simpler than just having overhead cams?

Adam