Most powerful Cobra engine

TheRobb · #1 (**permalink**) 06-19-2002, 07:55 PM

What have you guys came across, as being the most powerful engine you've seen or read about, in a cobra?

I know cobracountry had a Kirkham with a 427 and dual Paxton supechargers on it. Think it was 6 or 700 HP.

What have you guys seen?
How many people have engines turning similar HP?
(above the 514 crate engine).

I think I read someones sig had a 550ish with a supercharger! Thats some power!

(please feel free to provide details... engine, came, heads, etc)

thanks
-Robb

Venom S · #2 (**permalink**) 06-19-2002, 08:05 PM

Robb-

I'm about to start building my 521 ci BBF. Here is what I'm using:

SVO block (4 bolt center mains)
Scat stroker crank with H-beam rods and 10.5:1 forged pistons.
Mechanical roller cam (.663/.663 lift, 256/256 duration @ .050 lift)
Blue Thunder heads with Ferrea Racing valves (2.25 intake, 1.88 exhaust)
Single plane Victor Jr. manifold w/1050 cfm carb.

Using Desktop Dyno, the engine is estimared to produce 679 hp and about 600 pounds of torque.

Venom_S

Ikestaa · #3 (**permalink**) 06-19-2002, 08:15 PM

There is someone on this site who's cobra was featured as the Cobra of the Month. It has a claimed hp of 900+, why I have no idea

bmalone · #4 (**permalink**) 06-19-2002, 08:17 PM

There was a Cammer in a Contemporary running around Palm Springs area for quite a few years. Motor is now pulled and going in something else. The engine builder (same guy who did mine) said it put out 800 HP at the flywheel. I cannot even imagine how you would drive that.

Venom S · #5 (**permalink**) 06-19-2002, 08:18 PM

Getting 900 hp from a well built big block is not impossible. Will it survive long? Probably not. Will it be reliable? Probably not. Does it use pump gas? Nope!!

With an engine that big, you have to have 14:1 compression and run racing fuel.

Not very desireable for the street.

I know that even my motor with it's estimated 650+ horsepower will be a nightmare in a 2400 pound car. But that's me - different

Venom_S

BANDIT 1 · #6 (**permalink**) 06-19-2002, 08:53 PM

My engine will soon be 1,000 + horsepower (650 horsepower + 350 horsepower nitrous system (and ATI Pro Charger supercharger when available).

Tom-In-Ohio · #7 (**permalink**) 06-19-2002, 10:01 PM

Bandit,

When you fire that nitrous, you just might find yourself looping the Space Station.

Tom

ssirlin · #8 (**permalink**) 06-19-2002, 11:37 PM

Does that 1000 HP set up come with a neck brace ? Your chiropractor must love you !

RACER X #99 · #9 (**permalink**) 06-20-2002, 03:41 AM

HERE THEY GO AGAIN.

jrichard · #10 (**permalink**) 06-20-2002, 05:33 AM

last month's issue of HOTROD had a 1050hp motor that ran on 91 octane. it's a $30k piece of art that's evidently going in a boat. I guess there'd be no way to cool it with a radiator small enough for a car. Besides that, you'd have to run the softest slicks you can find to get the power to the pavement. That kind of power/weight ratio aproaches Motorcycle performance numbers, and Sprotbike rear tires only last 2000 miles at best...

BANDIT 1 · #11 (**permalink**) 06-20-2002, 05:45 AM

I have not hooked up the nitrous yet, I am waiting for ATI to finish the supercharger for the 460 engine family first. I did use a similar 350 horsepower nitrous system on my 69 Pro street Mach 1 (427 FE 650 horsepower + 350 horsepower nitrous) and it wasn't really no big deal (the difference was that the Mach 1 was set up for the power with huge slicks, roll cage, tubbed out (FORD narrowed 9") etc...).

jrichard · #12 (**permalink**) 06-20-2002, 07:26 AM

The engine I'm referring to in HotRod mag was NORMALLY aspirated, no supercharger/turbo/FI/NOS. Pretty cool. Unfortunately it would probably take a radiator the size of Rhode Island to keep it cool here in Texas.

Your Mach 1 (I love those cars!) was at least 1000lb heavier than your Cobra. You are going to tear up clutches/transmissions/u-joints and the competition with this monster. post pics when you can.

I used to build hi-torque Toyota FJ40 Landcruisers. It was pretty common to thrash u-joints and send the driveshaft wailing around tearing up sheet metal. consider a retainer strap or a shield around the driveshaft so when a u-joint does go, it won't take the fiberglass with it...

jrichard · #13 (**permalink**) 06-20-2002, 07:30 AM

and one more question: with the supercharger, how much hood/hoodscoop modification is going to be necessary? As a fellow SPF/460 owner the supercharger idea is tempting...

cobrashoch · #14 (**permalink**) 06-25-2002, 12:46 PM

Crankys right on this one guys. Horsepower numbers are mute. Using Cobra build orthodoxys of current thought, 500 honest horsepower is a very long reach when trying to put a leash on these beasts. The ONLY exception I can think of to this rule may be a JBL. And they even they say it shouldn't be done.
Jrichard - I've had some experiece w/Elegants as they were made in Indy. Is your car a stretch wheelbase car? Most of those cars will take centrifugal superchargers without mods if you mount them lowish. The 90 inch cars will need to be modified in the hood though and in both cases they need modified if you run a innercooler. If it is on a Corvette platform,with modifications it could take a bit more power than most Cobras but not that much as you will sacrifice handling. P.S. - My car is a N.H.R.A. approved attempt to be a exception to my statement above. Not only is my Cobra heavy by cobra standards it is built using a orthodoxy not discussed on this board.

cobrashock

Bill Wells · #15 (**permalink**) 06-25-2002, 01:07 PM

hmmm. a supercharger on a 460 under a spf hood and in that engine bay will be indeed tricky, if it can be done at all without body / hood mos, unless you have a contortionist method of installation. maybe you will be lucky and the ati s/c for a 460 family perhaps will be more accomodating than the ball drive paxton design of yesteryear. my 60's era vr-4 paxton on a 351 svo crate in my spf is a very tight fit but required no body / hood mods. if i had it on a single plane manifold instead of my dual plane the carb bonnet would hit the hood scoop when engine rocks under torque and would require the engine to be tied down more to prevent that from happening. i have the early spf version lower hood scoop however vs the slightly higher hood scoop on the newer spf's. have fun. bill

cobrashoch · #16 (**permalink**) 06-25-2002, 02:00 PM

Bill/Jrichard - The Vortec supercharger I am using on my derived 460 has a 5 inch intake and output. It is both heavy and BIG. Unless ATI has had some sort of break through I'm not aware of I don't see how they would fit a Superformance very well, as ATI's are now larger than Novi's and Vortec's but not the ball drive Paxtons. The key is the room in front of the engine, not above it. Also add to this is the fact that while the superchargers are made by Vortec and Paxton on big cubed motors they do not sell neat little kits of pulleys and brackets and pressure boxes and etc. to finish out these installs. Your on your own. VERY DISTURBING AND EXPENSIVE!
About 3 years ago I looked at ATI for the new promised big pump they said was forthcoming in a few months. HMMMMMMMM????
I keep coming back to my original premise of not if you can put one on (Yes,somehow you can) but rather if you should at all. And that goes double for a Superformance in my mind. Maybe the Elagant is somewhat O.K.
cobrashoch

Bowtie · #17 (**permalink**) 06-25-2002, 04:22 PM

Wow...after reading these posts I am humbled! I thought I was building a monster Cobra but seems I'm bout middle of the road. I wanted big HP numbers but wanted to maintain a usable idle and run pump gas so I started with a 454 Chev motor, put in 4.375 Diameter pistons and 325cc oval port aluminum heads...481 cubic inches. milled the pistons down for a 10.5 to 1 comp ratio (only 4.375 pistons I could find left me at 11.5 to 1...10.5 should be ok on 92 octane with the alum heads...) Victor jr, dominator, solid roller...should make about 570 (will dyno it before it goes in the car). I'm kinda shaky about getting the car to hook up...can't imagine what it would be like with 800, 900, or even a thousand hp!! If I can get the 60 foot times down in the low 1.50 range, a low or mid 11 E.T. isn't unreasonable...maybe even a high 10 on a cool morning?!?! We'll see....

jrichard · #18 (**permalink**) 06-25-2002, 05:51 PM

cobrashoch- yes, my Elegant is 6"longer and 3" wider than "normal" and it's on a '74 vette chassis with the center mount fuel tank. I have a modified 460with 280/288 duration cam and an Edelbrock 750 carb. Somewhere around 550hp at the crank. a blower will fit, but that's plenty of power for me. At least for now. But it sounds like fun to put a blower on it.

The SPF- it's a handful at 486hp and what, 2200lbs. It'll scratch the tires thru 3rd and gets sideways quick if you're not careful. not much room in front of the engine, that's for sure, and the aircleaner already touches the hoodscoop.

jrichard

Bill Wells · #19 (**permalink**) 06-25-2002, 07:12 PM

cobraschoch..."disturbing and expensive"..as you so wisely and correctly stated...is very true when there is no 'bolt on kit' for the chargers. Paxton ( old style ball drive) does not have one for the 351 either (289 and 302 yes) and alot of customization / fabrication was required ...but it does provide a unique look , rarity and sound. who said there were no expenses with this hobby ? hah....oops, that is what i told my wife but i got caught. now everything costs me double as she matches my $ one for one.....arrrggghhh....lets see, 4 tires at $100 each costs $800 !!! oh, love that modern math ! Bill.

cobrashoch · #20 (**permalink**) 06-25-2002, 08:00 PM

Bowtie - Your combo should produce the promised mid 11's easy. Don't forget you will weigh in at about 2500 lbs plus or minnus. What you will not like is your 60 ft. times. Most guys that run Cobras in the mid 11's sixty ft. at around 1.6 or 1.7. That's the nature of the beast! A mid 11 second blast with a drag car will usially have 1.3's sixty foot times so it shows you that most Cobras have that big end charge we all like. It's also been my experience that because of the 60 ft. times thing most Cobras will run about the same regardless of big block or small block. (sorry guys) There are a few guys out there that run them better but they are not the rule. Yes, you may see 10's if you go after that but I'm betting you will be having to much fun with your car to be doing such things. Welcome aboard to the madness train.
cobrashoch