New LS 4cyl Engine

Rttoys

Rttoys

Goblin Guru
I remember right before the LS came out that it was speculated to be a DOHC setup, because you can’t make enough power out of a push rod engine to keep up with the competition. Man, they were wrong.
 
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Desert Sasqwatch

Desert Sasqwatch

Goblin Guru
All the magic comes from moving air through the intake ports and out the exhaust. How many turns the air makes and what mechanical obstructions are encountered are primary factors. For an NA application, one big valve opened further is slightly less hindrance, by physical surface area, than 2 smaller valves, in theory. And the valve doesn't care if it's actuated by a follower finger or pushrod/rocker arm - as long as the valve train can maintain geometry and movement for a given engine rpm. I once helped build a SBC 327 (331) that dynoed at 555 HP at 7500 RPM for a dirt track car - it's amazing tthe power a 2 valve engine can generate.
 
Rttoys

Rttoys

Goblin Guru
Most of the nay sayers were from it being a pushrod, where you lose precision and energy through the push rods and such. OHC engines are far more precise and a Desmo Engine (like Ducati) even more so. Desmo engines are wild. My old Ducati is a marvel to look at and the new ones are even more awesome.
 
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G Atsma

Goblin Guru
The ONLY LS part of this engine is the head. The rest is based on an industrial design.
And don't be hard on pushrod engines. The LS V8 and dozens of others like it acquit themselves quite well.
OHC snobs need not apply....
 
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ah.b.normal

Goblin Guru
The block for this engine goes all the way back to the Nova 4 cyl released in 61(cam in block). This newest re-design deleted the steel push rod cover. Copying the LS head surface design, access to the lifters is now through the widened head/deck mating surface; changed due to the wider LS head. The Chevy I4 and I6 were used in cars and trucks and by Mercury Marine I/O applications, I've seen them in farm equipment(Combines) Ag pumps and generators as well. Pontiac built the OHC I6 of 1964 by recasting the Chevy 250 as a Pontiac block. Same bottom end, water jacket, pistons and rods, When GM built the "Pontiac Iron Duke" 4(back to push rods for Pontiac) in the 80's(different design cross flow head?) designers changed the bellhousing mount to the 60*V6(corporate/narrower for FWD) pattern.
 
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ah.b.normal

Goblin Guru
Working from the idea that it is roughly half of an aluminum headed smallblock chevy vs aluminum block and heads small block; IIRC weight savings on those is about 110#? So an aluminum block on this might save ~40#? (I question the cost/benefit here. Has anyone compared it's "Iron block/Aluminum head" weight to a Ecotec?(currently a mystery to me!) Putting DOHC's on a motor can be heaver than some folks imagine. + 1 cam and chain support/control appliances. On Ecotec, add balance shaft and it's mods.) This little 4 has persisted 60+ years due to the fact it has many other uses, the majority of which do not benefit from weight savings, BUT from cost savings. It was a big investment to recast this block with the widened deck and push rod cover face. I like the idea(WOOHOO!) but I don't Imagine this company is chasing that particular pot o' gold. ***Dangerous thinking ahead! Danger!*** On a tangential note: I am fairly sure that, in the 80's someone(Keith Black?) cast a Aluminum version for the GM Iron Duke. Put LS bolt holes in the deck mount the head. I'm pretty sure the Ls head bolts fall on the old narrower block deck. Then construct a pushrod cover/oil return cover with todays plastics and 3D printing. Oh, and don't forget to call me crazy because that usually causes some one else to go ahead and do it!
 
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ah.b.normal

Goblin Guru
Why thanks Dr. Squach! I know a compliment when I see one! (Remember, the real crazies will never consider the possibility they are crazy!) How crazy am I? This whole motor thing and I don’t even want one! The again I never used the offset capped rods idea I suggested to a 409 engine builder to gain pan rail clearance on stroker W motors and SBC. That guy sold them for a while and ended up making offset capped rods for Porsche Corp on contract. Funny, I got the idea from Brigs and Stratton.
 
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