Can a NA stroked Windsor really make 700 HP on pump gas?
 

http://www.cobracountry.com/cobra4sa...pitt/home.html

Really high RPM engine?


Pete

NASCAR 351W's are bored to 355 cid, the maximum allowed, and make right at 750 hp. This with a single four barrel carb AND a restrictor plate!

Figure cost at about $75K per motor. It will turn close to 9000 rpm but this DRAMATICALLY shortens the life of the motor. Best keep it around 8000 or so. If you lucky you can get 500 miles out of it. Classic engine problem with these motors? Valve trouble. broken springs or the valve coming apart and tearing up the piston. These engines are built extremely "loose". The pistons barely fit the bore for instance. They are a motor "on the edge". Miss a shift and you will blow it up.

351W stroked/bored to 427 (which is the MAXIMUM you can go and NOT recommended by me) with a single four barrel, yeah I can see 750 hp there. How long it will "live" if you USE all that horse power is another question!

But it do look good!

Ernie

But aren't NASCAR engines really high compression? Like 13 or 14:1? They would not run on pump gas - at least not for long!


Pete

They run on the SAME GAS you can buy at a 76 station! PUMP gas! Thats a NASCAR rule that goes WAY back.

There are two KEY things they do to get horse power.
1. Reduce internal friction to the point of being ridiculous.
2. Extreme head and valve train design (the BIG one).

Ernie

The motors are 14:1. You cannot produce that kind of power on a 10:1 motor. They do not use pump gas.

I have done the refueling at PIR in Phx when nascar is in town and they run 110 leaded...RR

We have 76 stations here, but I can't buy 110 octane at the PUMP here! Can anybody, anywhere?

If not, does it really qualify as "pump gas"? PSB is onto something (and NASCAR doesn't want you talking about their little secret I would guess)! LOL

Ernie

They don't run "pump gas" they are 14:1. They are about to switch to Sunoco instead of 76 anyway. I have seen many a windsor that makes 550 hp with less than 11:1 compression and staying below 7000 rpm, give those another three points of compression, move the powerband up 1000 rpm, and maybe. It wouldn't even think about being a street motor by then however.

You cannot pump leaded gas into your car anywhere in the U.S. You can certainly buy leaded race gas in containers from 76 or other outlets.

After reading the link, I think the seller is claiming that his motor makes 700 hp on 93 octane unleaded, based on his use of the term "pump gas" It does have some funny intake ports on those heads

Actually NASCAR engines right now are on a 12.5 to 1 compression rule and have been for three or four years now..... They use aftermarket blocks and all other parts are aftermarket top shelf parts,they turn as much as 9300 rpms and right now they are saying they are in the 750 to 800 hp range,running 110 octane leaded gas....The restrictor plate engines are in the 450 to 500 hp range....

They only run the engine one race and all engines are rebuilt after each race. Some of the parts are re-used but not that many,mostly cranks/rods/heads,most other parts are discarded after one race....Some teams even change valve springs after practice before the race. Those springs may have less than 100 miles on them....

You would be suprised to know they only run the rear ring and pinion one race and the rear end housing 3 races before changing them out... Also, all electronic boxes (MSD) are changed after every race,even the back-up box that may have never been used....

There are a number of sites that sell these used parts,some parts sell very low....

I think I remember reading on this site some time ago about a Cobra built for Goldberg (the wrestler) with an Ernie Elliot 454 stroker in it. It was built with mostly all NASCAR parts and said to make around 850 to 900 hp with a 930 cfm Holley.... I'm sure those NASCAR boys could build these engines and probably do,but I do not think they would be very street friendly or have a very long lifespan....


David

I have bought 100 octane low lead AvGas from a small private airport nearby. But I can't pull the car up to the pump. I have to pump it into a 5 gallon can, then carry it over and pour that into the car. PITA, but my engine loves that stuff...:JEKYLHYDE

Since you guys seem to know something a/b NASCAR.
I have always wonder why the air breathers you see
are always closed in front and flair out towards the
windshield. You would think they would use some kind
of cold air intake duct running to the front , and take
atvantage of "forced air" to create a supercharger effect.
Just always wanted to know - maybe someone could inform
me.
WB

David has it right. I have a detuned version and it was not 75k for the motor. Closer to 15k. It has 7500 miles, plenty of track time. All I have done is change plugs, change the oil, adjust the valves and replace broken tranny and rear end parts. 12 to 1 compression, 660hp at 7200, 358ci. It is very streetable. I run pump gas on the street without any problems. The tires spin so there is not much load plus with 3.89 gears, it cranks up fast. On the track, race gas as thmotor is loaded and thrashed with slicks. The power is obviously there, but the longevity of the motor is the reason that I would do it again. I have been wondering about the valve springs, allthough it was seeing 8200 rpm at road america without valve float so I will keep my fingers crossed. scott

If Ernie Elliott built the motor...bank on it being spot on the stated hp and torque. There are only a few Ford builders in the USA in Elliotts range...
As for the air cleaner, they draw from the windshield area because that it the best place to RELIABLY draw fresh intake charge. The front of the car can get crushed in a friendly tap session, covered by debris or merely blocked by running in close order. There is a ram air effect at the trailing edge of the hood, much better than our type of scoop, which is also why the Thunderbolts had a reverse opening scoop.

Robert is correct, there is a high pressure area at the base of the windshield.

Also, here is a stock displacement 360 with tests of different manifolds and flat tappet cams. Add a few more cubes and custom intake and who knows.

http://www.hughesengines.com/www/hug..._dyno_test.asp

The high pressure area at the base of the windshield was the whole theory behind the old cowl induction Chevell's (supposedly the only production car ram air that really worked as advertised I remember reading somewhere)

have a good one,
Dan

first generation camaro's also had a good cowl induction hood, it was RPO ZL-2. Smokey Yunik's 66 chevelle had cowl induction, the aircleaner housing attached to where the heater core is supposed to be on the firewall, it sucked air through the vents at the base of the windshield. Later chevelle's had the aircleaner mate up to the underside of the hood, with a flapper door at the rear of the hood, that would open under demand.

This is nothing new. Unique Motorcars has been installing Elliot built stroker windsors in customer cars for years. I don't recall the horsepower ratings, though, but an early one was featured in Nov '92 Kit Car with 565 HP. That engine was stroked to only 358 ci and ran a 10:1 compression ratio (I think some later versions went as high as 454 cubes). Turnkey price was listed at around $75K. An Elliott powered Unique also graced the cover of the famous Dec '91 issue of Car & Driver with the big Pat Bedard Cobra article. Interestingly, I recall reading in one of the articles that during intial testing, Elliott's best efforts failed to destroy the stock Jag IRS and one owner ran his hard for years including numerous dragstrip passes with no breakage.

This is a pic of the Unique "Nascar Cobra" as it appeared on the cover of the C/D issue. Interesting that Ole Shel decided to paint his Elliott cars the same solid red as the Unique "original". Hey ... who's driving a REPLICA now? :LOL: :LOL: