Engine talk

[TassieCobra]

Hi all,

Apologies if there is already a thread about this but I could seem to find one.

I am in the early stages of a cobra build and are still deciding on the choice of engine. I would really value your opinion.

I would love to have an "old school" sounding engine with all of the burping and farting at idle but are weighing this up against the newer/higher performing and probably easier to maintain engines.

Could I get some thoughts from the group about what the best new but "retro" engine they would choose for awesome sound if they had their time again (eg windsor vs coyote vs godzilla vs LSA vs others). Performance is important of course but for this thread I am mainly interested in the sound/fun factor.

Thanks in advance

Addit:

Thanks to everyone for all of the great advice. To give more information I am based in Australia (Victoria or Tasmania for registration purposes). I am looking at a higher end Cobra build with an aluminium body. The manufacturer can accommodate a variety engine choices/mounts. As pointed out though I suspect we will have more stringent emission requirements etc.

Thanks again

[Unique427]

There's a large menu to choose from, but if you want the "burp/fart" sound
nothing sounds like a naturally aspirated Ford 427 FE Side Oiler configuration.
Topped with the eye candy of a polished fuel injected 8 stack.

Find the right builder with proper components and it will be dependable.

Also consider a proper color scheme that complements that engine jewelry.

If you ever decide to sell, open the hood and that buyer's reaction is .....

[Tommy]

Engine sound is also very important to me and I like the old school sound of high compression and a big cam at idle. But sound is also very individual like beauty. All I can offer is that I loved the sound of the 408 ci Windsor in the Cobra I used to have. Of course it was heavily modified with aftermarket crank, pistons, heads, cam, etc. . . When I started building my Cheetah tribute my goal was to have a sound much like the Cobra. It has a 427 ci Chevy engine with all aftermarket components that hit 600 HP on the engine dyno. It sounds good, but I still like the Cobra a little better.

Here's a short video of the Cheetah at idle.
Video

[Grubby]

427 Side Oiler.

No other choice for a high end S/C build

John

[twobjshelbys]

Search will find you plenty of topics on this subject...

You don't say what base Cobra you are considering. Alot will have to do with what the ending config you desire. Don't put a 50K engine in a 40K car.

Windsor based. Lots of displacement options available. And you can get one that will shake you to death at idle if you get the right cam but it's much easier to build a streetable car with one.

Used "side oilers" are a crap shoot. You never know what you're getting and mistakes can be expensive. Modern incarnations like from Shelby are also expensive.

I would avoid the Coyote. The Cobra group is still pretty old school and cars with Coyotes are harder to sell. Cars with Chevy engines are even harder sells.

Godzilla is a tight fit although someone did manage to put one in - I don't know if there's a topic here but my recollection was the car was built knowing it was going to be used because it wouldn't fit in a standard Cobra configuration.

[letsboogie351]

If you are in the early stages of a build you will probably find that your engine choice will be limited to what you can get through emissions test.

[twobjshelbys]

Originally Posted by letsboogie351

If you are in the early stages of a build you will probably find that your engine choice will be limited to what you can get through emissions test.

Yes. Not only do we need to know what direction you are going but where you live. If you are, for example, in Australia, a Coyote may be among your top choices...

[Hapnyny]

Hi!

I recently had gone through this exact dilemma. I have a CR with a ERA correct 289 but wanted more than the 274hp. I did a lot of research with history search. What I found out was the Cobra handled better with the 289 over the 427 according to the original drivers that dominated back in the 60’s. Caroll Shelby jumped to a 427 to keep up with the Corvette’s. In a documentary the question came up to Caroll if you had a choice of Cobra what would you want. Carroll said a 289 with an automatic would be his choice. I was surprised but I final figured out why he said it. The 289 was the perfect motor for the AC for SCCA racing. For street use the 427 was the best choice. I ended up going with a 347 Stroker from Prestige Motors pushing 483 HP and 434 TRQ. Waiting for the motor to be shipped to me this winter. I felt that I was able to take advantage of a small block pushing big block hp. The automatic piece that Carroll spoke about was more about always having control of the drivetrain all the time and never a break in between gear changes.

[Hapnyny]

A link to a 347 Stroker 500 HP, I think this is what your looking for? I was going to get the 363 Stroker 7K RPM pushing 575HP but it was $5k more in price. I paid $15k for my engine. I also added my engine build as well on the dyno, small but strong. I went for weight reduction and I was able to use my existing headers and side pipes with this motor.


https://youtube.com/shorts/lmNs7ZLeLHs?feature=share

https://youtu.be/dKgfhkReNkc

[xb-60]

TassieCobra,
Your best route for deciding on engine selection is to talk to your local Cobra community. They will tell you what you can and can't do legally.
I'm starting to feel like an advocate for the Victorian Cobra Club here - your best bet is to (if you're not already a member) go to a club meeting and talk to people who have started down the same path as you. Theirs would be the best advice you can get if you want something you can drive legally on the road.

Cheers!
Glen

[Hapnyny]

Glen is correct,

Your DMV will be a deciding choice on what you can do to get it titled. Local members can give you an insight on what you can expect with your choice of engine.

Good luck!

[eschaider]

Well, why don't we start with what kit you are beginning this adventure with? No real point in trimming the tree untill you plant the seed and grow or start to grow one.

[twobjshelbys]

Glen (XB-60) seems to be pretty sure that the OP is in Australia - perhaps from his screen name, maybe Tasmania? If he is, all of our US-based and biased advice is moot. Their choices come down to only a few and get further restricted depending on the kit.

OP, please clarify your location and what kit you plan on starting with.

Probably scared the dude away

[eschaider]

The OP has a brushed aluminum one in his pic gallery so I am suspecting it is one of the aluminum Australian manufactured Cobras.

[Tommy]

I seem to be the only one who noted that the OP wanted to know about the sound of various engine choices, not the legality or desirability for any other reasons.

[eschaider]

Your eyes hear better than the rest of us Tommy.

[eschaider]

To the OP,

If you want one of those '60s rock and roll sort of performance car idles, you can do it by tightening up your camshaft's lobe separation angle (LSA). Go down to a 104 to 108 LSA (104 on a SB nd 108 on a BB). You'll get a 800 to 1000 rpm rock and roll sort of idle. Be prepared to keep the engine speed at or slightly above 1800/2000 rpm driving with that kind of idle.

CompCams has several grinds specifically designed to do that. They call them mutha-thumpers.

[xb-60]

Originally Posted by Tommy

I seem to be the only one who noted that the OP wanted to know about the sound of various engine choices, not the legality or desirability for any other reasons.

Valid point Tommy .... but if a new builder doesn't know the legal situation and proceeds to build a re-hot (but great sounding) Cobra replica that then can't be registered for road use, that might be a problem. Would be for me anyway. Doesn't matter how good an engine sounds if you can't legally drive it on the road..... if you want to drive it on the road

Cheers!
Glen

[Tommy]

Glen - you make valid points. But there is a more fundamental issue here.

I am usually the person who has already done some research and not found the answer to my question before I post it. So I will ask either an open ended question or a very specific one. I find responses that don't address specific questions to be somewhat annoying. For example: "Who here has actually used Brand X carburetor?" Response: "My buddy has a Brand Y and he likes it a lot." That response was not useful IMHO.

On the other hand we have all seen a question from someone who plainly did not know what question they should have asked. Example: "My engine dies after about twenty minutes. What octane gasoline do you guys use?" . . . So the challenge for those of us who want to be helpful is to read between the lines and reply in a way that both answers the OP's question AND suggests the question they should have asked.

Getting back to this thread, it appears to me that someone answered the question he thought the OP should have asked and then lots of folks started down that path. I'm simply suggesting that it could have been better if members first answered the OP's specific question and then offered advice on the question he should have asked.

[eschaider]

For the OP;

The engine oiling system has nothing to do with exhaust note. Side oiler, top oiler, no oiler — no difference in exhaust note.

Your engine sound wil be primarily affected by your compression ratio, camshaft lobe separation angle (LSA) and your cam phasing. There are excellent sounding big blocks, small blocks and even transplants like certain GM engines.

Any of the modern 4V EFI equipped engines will disappoint you with respect to the exhaust note. They tend to be sewing machine like in their idle note consistency — no audible change in note. They are reliable, start in any weather, don't leak oil and some make monstrous power.

In the end this Advanced Engine Decision Tree Logic Chart will probably be the most helpful for you;




p.s. Your first consideration should be getting it through Australian certification. Once you have done that you can always put the camshaft in that produces the exhaust note you want.