yawn, you go with that. drag racing is the most HP per package size, weight and cost. That is clearly OHV. Please find me something like the pump gas shoot out any DOHC. I followed the Supra guy for a while with the 2JZ, lots of promises lots of problems, and as far as I know he never once actually finished the pump gas drags despite the claims 1000 HP dyno runs.
http://www.hotrod.com/articles/hrdp-...ump-gas-drags/
Nutshell, simple rules: drivable, on gas, who wins? OHV.
If I was not a big DOHC, I would not have followed the Supra to see if he could bring it, he can't.
Will the new 5.0 with crazy mods be at the 2018 pump gas shoot out, I hope so. Will DOHC dominate say in 10 years? dunno I doubt it. Why do I doubt it? The engine has 4 inch bore centers, meaning that there is all kinds of heat and sealing issues. Why does it have 4.0 bore centers? simple cause DOHC engines are so friggen huge externally, if the engine had 4.4 bore centers Ford could only put it in a large truck. Also there is crankshaft whip issue with a small bore center engine at high RPM as the harmonics creep up and down the shaft vs less bearing area (mains are seated between bore centers). So there ya go. Reasonable cost performance favors the bigger short block with more cooling and sealing, with more main bearing surface and less need for RPM to make HP.
From Honda racing there is a max of 9500 PEAK RPM for shot durations like an autocross on a 86mm stroke engine (27.233 meters / second). Any further increase in RPM results in the breakdown of the oil film of the piston and bore. Ford is pushing 93 mm with the Voodoo, looks like the at 8250 RPM (25.575 m/s), quick number crunch 8800 RPM PEAK for shot durations (27.1 m/s) is the limit, Ford is really close to oil film breakdown stock. So a really crazy NA build that could incease peak HP and RPM would be limited to oil film to 8500 RPM with a fuel cut at 8800 would wield a build of 526 HP x 1.13 increase in engine speed breather = 600 HP. Sure this is a ball park figure, but you can see there is a limit to a 4.0 bore spaced engine.
For grins the LS7 has a 101.6 stroke so give the same max piston speed: 8500 rpm for 27.s m/s, clearly the LS7 even in its most wild configuration is not going to hit a piston speed issue. As an aside the limit to a OHV engine without cam in cam technology or some sort of rocker arm VTEC would be the ability to idle, given a 7 liter LT1 engine and maintain some drivability say 700 to 750 HP, depending on one's definition of idle and drivability. Pray is already pushing 600 WHP on what would appear to be a daily driver, Katch is at 707 STP engine HP on a 7.0, so I'm probably pretty close. Maybe with the Victory JR head and kooks headers could get a little more. Basically take the intake flow number x2 = engine HP.
Take away the limit is not the breathing it is the stroke and it is going to get really hard to get more HP. Hence Ford has hit two dead ends: can't bore, and can't stroke. The OHV engine is just fine. Hence just about any discussion about the 5.0 has to turn into but if you add a supercharger.. cause they (5.0 buffs) have no other option.
http://www.chevyhardcore.com/tech-st...the-winner-is/
So for a drivable engine on a $10,000 build the Coyote is about 520 HP, say 550 HP on the new direct inject. A 7 liter texas speed crate engine is about 700 HP. Torque of course follows, at no time will the Coyote put out more peak torque vs the minimum torque of a 7.0 over its applied band, which is really important in an autoX. huge bucks 5.2 DOHC build I'm saying 600 HP is a nearly impossible wall to climb due to oil film issues, no matter what the dyno says. For the LT1 OHV, it is idle and driveability at 700 to 750 HP, maybe a little more with E85 and Victor JR heads, and way way way way cheaper. That is an impossible gulf to swim.
Sans FI, on the street it is going to be HARD to beat a LT1, Ford engine too weak, Dodge is too heavy.
Like I stated a while back there was a REALLY quick Mustang at the drags I went over to see what was under the hood, thinking 351C or 460, something, nope LS engine.
Actually I would absolutely love to see a NA, 9000 or 10,000 rpm DOHC V8 drag engine. Note due to the stoke and oil film AFAIK you won't see a 5.0 or 5.2 doing the same RPM on the AutoX, unless it is trailered in and engine toss every once in a while.