Performance Questions 225 vs. 360

RE your 360 V8 car: Will it wax THIS one?

Turbo Slant Six 10.74 @ 127 mph 7-19-10 - YouTube

or this one?

Turbo charged Slant 6 11.02 @ 120.56 - YouTube

Neither of those cars has a roller cam, nor fuel injection, nor high compresssion (it's 9:1,) nor deep gearing (they both have 2.73:1 ring and pinions.)

Neither car turns over 5,500 rpm.

Both cars have a smooth idle and drive-ability pretty much like a stock /6 because the cams in these engines only have about 220 degrees of duration, and very little overlap.

They both have one Holley 4bbl carb, and ignition sytems that are very close to "stock." That works because the RPM's are never much over 5,500.

They each have a homemade header, a ported head and 1.75"/1.5" valves.

If you want a fast slant six, you either need to put it in a very light car (like Guzzi Mark did, with his normally-aspirated 225; 2,350 pounds) OR use some sort of power adder, like a turbo, supercharger, ot nitrous. )

The fact is, the bores in this /6 are so small, there is just not room for really big valves. The head was designed for 170 cubic inches, and Ma Mopar did NOTHING to increase the breathing ability of it when the displacement was increased 35-percent (to 225.)

NOTHING.

You can add speed parts that are aimed at enhancing the breathing ability, such as headers, bigger valves, a 4-barrel intake system, and raise the compression to 12:1, but it is never going to make really good power, (over 2 hp/cu. in.,) normally-aspirated, because the breathing potential is just not there.

The two guys in the You Tube videos are both making around 500 horsepower and doing it without "heroic measures," such as roller cams, high rpms or even fuel injection.

They both use Wiseco forged pistons, and K-1 (198 dimensions) rods and a stock forged crank.

Other than spending about $1,400.00 for a ported, big-valve head, the pistons and rods are the only expensive items in their engines.

I'm not contending that a 500hp slant six is cheap to build, but the parts list is not populated with thngs like high-dollar roller rockers, custom pushrods, and expensive valve springs.

A new, Holley 4150, 650cfm carb, built to "blow-thru" specs is not cheap, and neither is a Snowperformanxe Boost Cooler alky-water injector, but an expensive, hi-stall converter is not necessary, like it might be with the choice of a radical-cammed 360.

The fact that originally, the /6 was designed to be built out of aluminum (and, 60.000 were, before Ma pulled the plug,) caused the infrastructure of that engine to be built super-strong, almost like a Diesel. The main bearings, for instance, are the same sixe as the mains in a 426 Hemi.

That set of circumstances make it a natural for utilizing forced induction, as large amounts of boost don't seem to hurt it. The cars in the You Tube videos both routinely, run over 25 pounds of boost.


I think that 25 pounds of boost would not be a very good idea on my Vortech supercharged 360 Magnum.:prayer::prayer::prayer:

FABO member Pishta's low-boost /6 project is a low-cost alternative to conventional hop-up methods of increasing the power out of the /6, but I think that the 500HP cars in the videos are not unusually expensive bullds, considering the amount of performance they achieve.

Add up the costs associated with building a normally-asprated small block that will go 127mph in the quarter mle in an A-Body that hasn't been "lightened,"(the one in the video hasn't.)

It won't be cheap.



Bill,
Your argument is old and tired. I would have a lot more respect for you if you used video of your "own" build,instead of the same old videos you trot out every time this issue comes out. I'm still waiting to see any kind of time slip out of you. I don't think I have seen your car make it out of the driveway yet. And how long have you been working on that thing ?

The fact of the matter is the OP is not going to build a turbo,and will stay naturally aspirated.
You build a naturally aspirated /6 Bill, and I will build a junkyard 360.
Be ready to put your lipstick on Bill,because you will be kissing my tail lights all day long ! Lol