03 cobra motor

[sstjet]

Just an idea I wanted to throw out there and get some feedback on. I was thinking putting a 03 mustang cobra motor in a jetboat would be pretty cool. Possibily swapping the blower for a turbo. These motors are pretty bulletproof stock up to 1000hp in cars. What do you guys think?

[George Pataki]

4.6 liter?
I'd be interested in seeing that.

[Bow Tie Omega]

Oh man, break out the popcorn:D All kidding aside, car motors and boat motors are different. Bearing clearances, valves, cam, exhaust, ignition, etc, all different. Now adding to it a computer management system? Not impossible, but alot of work...... But, I have always been a sucker for doing what people say is a waste of time or can not be done. If you are trying to be the fastest boat on the water, I would not do it personally unless you have alot of $$$ to throw at this project. But if you are just trying to be different and try something cool, I say go for it. I would appreciate the work alone that would be involved in such a venture. Just my two cents. Hope it works out and good luck

[pw_Tony]

Does the 03 Cobra motor make enough power at a lower RPM? I could be wrong but I think peak torque is like 4500RPM and peak HP at 6000rpm

[Placecraft Dragstar]

No replacement for displacement.

[SmokinLowriderSS]

If you think you can get that 1,000 HP down to 6,000 RPM, go for it and impress everyone.
4.6L!??!?!!??!!?
"E" impeller cut???????
I think that's a crappy idea, but, go for it. Somebody has to be the guinea pig for the new stuff to prove the bad ideas really ARE bad ideas. I might be wrong.

[75 spectra V-drive]

I have an 03 cobra. Trust me the bottom end is not bullit proof to 1000 hp:mad: or even 700hp. my new set up has ported heads,studs throught,headers,larger heat exchanger,larger radiator,with a kenne bell running 10lbs . I now have what I think is a safe tune 526 rwhp,It does not make good power untill 3500 rpm. cool idea, but I dont think it would make a good boat motor. just my .02

[VAMI]

I think youd have a huge headache and a empty wallet.There is a twin turbo nissan 4.5 or 4.6 on youtube that is BADAZZ.

[AaronL]

No replacement for displacement.
Boost replaces displacement pretty good in my opinion.
Here's some info on a friend's car that I helped build all the turbo stuff (headers, intake, etc..):
These are rear wheel dyno numbers (corrected) from a stock cube small block LS1 with twin t76's(camaro):
12 psi and 75 shot 919rwhp 880rwtq
He ran high 9's in a 3500lb car.
These numbers were around 6,800 rpm. Pretty good torque #'s too. I wish I had the dyno sheet to see how low the numbers were down in the lower rpm's, but I don't.
To me, the above numbers look like they would work pretty good with an A impeller. Maybe I'm wrong though...
Go with twins for good looks!
http://intakeelbows.com/ttls101.jpg
http://intakeelbows.com/chadtt.jpg
I say go for it and try to prove everyone wrong that is stuck in their old 'big block only' ways. It is always cool to see something out of the ordinary that kicks ass. Like everyone else that has posted so far, I have no personal experience trying something like this, so everything I have said is just an opinion (in other words, don't say I don't know what the hell I'm talking about, because I'm already aware of that). :)

[ap67et10]

I have an 03 cobra. Trust me the bottom end is not bullit proof to 1000 hp:mad: or even 700hp. my new set up has ported heads,studs throught,headers,larger heat exchanger,larger radiator,with a kenne bell running 10lbs . I now have what I think is a safe tune 526 rwhp,It does not make good power untill 3500 rpm. cool idea, but I dont think it would make a good boat motor. just my .02
just curious to know what happened to the original engine in your cobra? how did it blow up? (i'm assuming it did) what was the set up?
i had a friend that also had an 03 cobra with exhaust, reconfigured engine management, port and polished factory blower with small pulley. 14lbs if i remember right. but thats it...nothing else and he chassis dynoed at 595 rwhp. from what i found out from him those things are basically bulletproof in the sense that if you supply the correct amount of timing fuel and boost the bottom ends will hold together up to around 1000hp. factory forged everything, h-beam rods...definately not your average stock factory engine.
personally i think that would be a wicked set up! last time i checked a 1000hp is a 1000hp and you would be one of very few that could say you are packing it. somehow a 600hp bbc in a good hull can do 90-100 but a (probably lighter) 1000hp 4.6l efi overhead cam 32 valve....wait a minuite why is this not an awesome idea??? and why would anyone in there right mind say that it wouldn't run good or wouldn't be able to spank just about everyone out there? as long as you set the pump up right to be most efficient with the engines power bands your good to go. itd be sweet. probably have to fabricate a lot of parts ....a lot of parts, but if your up for that than go for it!
whats stopping you?
AP

[ck7684]

Go for it!! Biggest issue might be engine management...you dont even need 1000hp...

[George Pataki]

SSTJET if you need any Fabrication work done.
Shouldnt be a big deal with us being neighbors now!
Keep me posted so we can get this deal wet by spring!

[sstjet]

Just a pipe dream now, wanted to get some feedback though. You know I am a blue oval guy. Besides I like to be different so a 32 valve 4.6 would fit the bill. Btw I don't have to set any records!

[SmokinLowriderSS]

These are rear wheel dyno numbers (corrected) from a stock cube small block LS1 with twin t76's(camaro):
12 psi and 75 shot 919rwhp 880rwtq
These numbers were around 6,800 rpm.
To me, the above numbers look like they would work pretty good with an A impeller. Maybe I'm wrong though...
A year + ago, a guy had a 718 HP N/A 502, that should have been good to an A impeller as well.
I run an A impeller.
I was turning mine 5,000RPM, on a 400HP 454.
He was turning it 4,000 MAX, on his 718HP 502.
Seriously WEAK low-range torque and HP production hung him up.
Bad parts & machine work choices did it to him.
WAY too much cam duration & way too much head flow ability (huge valves and hogged to the max ports)

[ap67et10]

A year + ago, a guy had a 718 HP N/A 502, that should have been good to an A impeller as well.
I run an A impeller.
I was turning mine 5,000RPM, on a 400HP 454.
He was turning it 4,000 MAX, on his 718HP 502.
Seriously WEAK low-range torque and HP production hung him up.
Bad parts & machine work choices did it to him.
WAY too much cam duration & way too much head flow ability (huge valves and hogged to the max ports)
i find it slightly hard to believe that a 502 who's peak power output was 718hp can't make 200hp at 4000rpm. that is what the chart says it takes to spin an A at 4,000. if he can't go past that he must not be making that 200hp at 4.000 or theres something else that is the problem. so what was the end result of this 4,000 rpm 700hp boat? what did he change? how did he get more rpm? even with the biggest cam possible and the biggest valves possible and whatever else you can find that is the biggest and baddest out there. if you took all of it and put it on a 502 i garantee it would make more than 200hp at 4000 rpms. there was something else wrong. its not just big parts.
clearly this proves that your little boosted 32valve 4.6l won't work. your better off putting in a big block with a tunnel ram and headers. cause thats a way better idea!
personally i would do it just to confuse people. and just think if one of these people trapped inside the tunnel ram big block box got it handed to them by a 4.6l 32 valvle v8!!! you might as well be an import!!! i mean geezz 4.6L!!! how many cubic inches is that anyways!!! :jawdrop:
It annoying listening to a lack of optimism with something completely different. especially when its an awsome original idea. I really hope to see this take off!
AP

[dmontzsta]

You can get 500hp out of a Cobra motor with little effort. It weighs a lot less than a big block as well. I think it would be pretty cool, dual overhead cam will definitely help...

[Cole Trickle]

What about the 5.4L out of a Lightning?
Not sure how long it would last at high RPM's in a boat but it sure would be cool.:)

[dmontzsta]

I am sure it could be tuned to run fine in a boat. The newer overhead cam motors are made for running at higher rpm, a lot more so than a 40+ year old big block design.

[Cole Trickle]

I am sure it could be tuned to run fine in a boat. The newer overhead cam motors are made for running at higher rpm, a lot more so than a 40+ year old big block design.
Remember it's a ford;):( :eek: :D

[sstjet]

5.4 lightning I don't believe has as strong of a bottom end as the cobra motor, I could be wrong though. Also you would have to swap heads from the cobra, because the lightning only has 16v heads not 32v heads. The added diplacement would be nice though.

[455Rocket]

Sounds like the bottom line here is reliability... why the hell spend so much coin on a small block and then wait for it to blow up turning 5K on the river all day long?
Come on guys...

[sstjet]

03 cobra motor is said by many to be the strongest motor ford has ever built. Ford GT and SHELBY GT500 are variations of the same motor. Reliability would not be sacrificed with this motor. These motors rev high easily, they have no pushrods and all forged internals.

[Bow Tie Omega]

Sounds like the bottom line here is reliability... why the hell spend so much coin on a small block and then wait for it to blow up turning 5K on the river all day long?
Come on guys...
I could take your remarks about this project, plug in 455 Olds and what you said would be absolutely true:D
Sorry, could not resist

[SmokinLowriderSS]

i find it slightly hard to believe that a 502 who's peak power output was 718hp can't make 200hp at 4000rpm. that is what the chart says it takes to spin an A at 4,000. if he can't go past that he must not be making that 200hp at 4.000 or theres something else that is the problem.
Unless he was lying when asking for help, his problems were exactly as I related.
I did some engine modeling work on Desktop Dyno to try to get and give him a better idea of exactly what was happening.
My version came up at 709HP@ 7-grand, 714 at 7,500, v ery close to his claimed actual dyno run.
Cam was .629 lift roller cam, 306* intake duration, 260* exhaust duration (.050" specs). That is one HUGE cam, 63* overlap.
Rectangle port heads he claimed to have had "fully race ported", with 2.3" intakes and 2" exhaust valves.
I no longer have the pm's, so I no longer have any idea whose rectangle heads he started with, but I still have the setup on DD.
Single 850 holley atop a tunnel ram manifold.
Nothing about the setup was designed to provide mixture flow velocity worth a damn in the 4,000 to 5,000 RPM range, and the "A" impeller he had would not let him turn faster.
My intention was simply a warming to try to make enough power down low with the little motor to be able to get to the bigger power higher up.
Careful parts selection and setup.
so what was the end result of this 4,000 rpm 700hp boat? what did he change? how did he get more rpm?
I wish he had gotten back to the board with the improved version. :( I never heard from him again after he decided a cam change was a definite starting point and was trying to decide what to do about the hogged out head runners.
More folks that I were interested in improvements in it.
even with the biggest cam possible and the biggest valves possible and whatever else you can find that is the biggest and baddest out there
He had them, unless you wish to claim he was lying.
if you took all of it and put it on a 502 i garantee it would make more than 200hp at 4000 rpms. there was something else wrong. its not just big parts. Well, his wouldn't, even at 11:1 compression.
Again, I was spinning the same impeller, with 50 cubes less displacement, at 8.?:1, thru dead stock '049 heads (orriginal per 1978), with small factory valves, a dual-plane manifold, only 700 CFM of Holley, a thousand RPM higher, pushing my heavy old Taylor to 65 mph, while he was getting 45.
Unless of course, he was lying to us all.
I'm looking for the original thread.