JTB

This is my buddy's car, engine specs are at the end of the Vid.

osso12

what does N/A mean? Not allowed?

osso12

I see the numbers.. but not buying it on the consensus is a stock 5.0 block will shred itself at 500 hp... is this a mustang dyno? Why did it take to the 5th pull to get those results when it should easily get the results on second or third pull? not buying it.

JTB

Wow..


Lmao!

The Dyno was a dynojet.

You may want to do a little bit of research on the letters PSP before you post your BS.

tulowd

Hello: The car in the video belongs to me; please let me explain a few things.

N/A stands for Naturally Aspirated; in this case the motor is carbureted, but could also be EFI'd (Electronically Fuel Injected) without a power adder like turbo, nitrous or blower.

You are correct that most accomplished engine builders use 500 or 550 hp as the limit for a stock block pushrod 5.0. This doesn't mean it blows up the moment it goes past 499 hp, but rather that the limit of the block has been reached. They typically break the block webbing near one of the middle bearing caps or in other places. This is usually brought on by the shock loads from launching the car hard with a sticky tire and big gear (torque multiplication, travelling forwards to the engine). Drag racing is much harder on the whole drivetrain than street driving or road racing. I built this car for the latter two purposes.


The engine was fully blueprinted, machined and assembled by Paul Silva of PSP Racing. He is the brother of Joe D'Silva and one of the pre eminent SBF engine builders on the planet. 333 cid, 10.6:1 comp; Shell 91 fuel; locked out timing at 34*.


Internally (zero) balanced, lightweight forged pistons, crank and H beam rods; alum flywheel and alum ATI damper makes for a lighter, properly balanced rotating assembly. The block main caps were align honed and ARP studded and have a 0.500" steel main girdle tying them all together. The lifter valley has two tool steel girdles tying the cylinder banks together.
Heads have rocker stud girdles. Motor is fully studded and uses Cometic head gaskets. Most of this is overkill for the build, but my goal was to keep the motor lightweight and produce 500 hp, which it now does.


The 5 pulls were done with the MSD rev limiter set to 6500, 6700, 6900 , 7000 and finally 7200 rpm. The dyno needs to see the rpm go past the peak in order to properly see the drum acceleration. We kept turning it higher and higher. As expected, the max power appears to be just over 6500 rpm, which is the typical limit of hydraulic roller lifters; Crane race lifters in this particular case. The retainers are made of lightweight tool steel and save about 10 grams, which theoretically gives the valvetrain app 500 rpm more peak range.


If this was done on a Mustang Dyno, the figures would be app 15% lower, since the format of an electric motor resisting the torque is a different animal.


This car has done 5 different dyno sessions (app 50 pulls) on 4 different dynos. With the old iron heads it made 374, 378 and 379 rwhp last year.
The only changes this time around are the smaller BBK headers (took off the KOOKs), porting the same Victor Jr intake, and the brand new (2014 castings) Victor Jr heads, fully ported by Paul Silva. The car picked up just shy of 60 rwhp ,so that is pretty significant and we are all very pleased and surprised by the results. I figured on having to go solid roller to achieve this number.


Given the weight of the car is exactly 3500 lbs (with driver and half tank of fuel) the mph in the 1/4 mile will determine what the actual horsepower at the tires is. Hoping to see 120 mph, but will be happy with anything over 115.


I hope this clarifies your questions and comments.


thx
Paul