Interesting 351C engine info

[dingocooke]

Had some discussion with Dave Webb at AFD re my proposed 351C build, and heres what he had to say (I asked him about cam choice, inlet choice, whether to go stroker or not and the effect, and what compression ratio he would reccomend using alloy heads for a street motor that would see stop start traffic sometimes so needed to behave!)

He said:

'There are thousands of combo's out there and we find there are a few combo foundations that work over and above the general way of it being done.

It is a big advantage to have at least 10.5:1 compression ratio in your engine.
Our 2V alloy heads will take your exsisting exhaust system no problem.
If you would like to stick with a hydraulic camshaft, I would suggest stepping up to CompXE 284H camshaft. It is more aggressive (than my current comp cams 270H) and will provide good drivability with plenty of power to 65000rpm. We have had great results from this cam many times over.

The intake will depend on how much hood clearance you have in the cobra.The longer, taller the runners in the manifold, the more torque and horsepower it will create.
A TFC 2v intake from australia is probably the best intake, but it is 6.250" tall and may not be too good if your hood doesn't shut! Other than that any normal 2v style will fit, I would have the Edelbrock torquer on there as a second choice to the TFC if you have hood clearance issues with an intake that tall.

You are much better off getting the cam from the US yourself. It is a Comp Cams XE lobe part # 284H and is an off the shelf item.
This combo typically makes 480hp and 450 ft pounds of torque with a very broad torque curve, and it is very drivable with a 3.3 or better rear end ratio (note my car has 3.31 IRS)

It is always better to use aftermarket crank, pistons and rods, they now cost very little and will always be stronger than the factory parts, lighter as well.The cost of a stroker crank is generally the same as a replacement stock stroke item, so stroking the engine really doesn't end up costing much more. We use scat stroker kits; I find them good quality and a little cheaper to balance.
The comp ratio will run all day every day at 10;1. It is very conservative cr when it comes to a cam and alloy heads on a 351C. The diff gear ratio is what is needed to run that cam and have the engine behave itself when cruising around.
You can safely run 10.8:1 compression. I assume you have better fuel available to you than the Americans do; they do not get 98 fuel like here in OZ, that's why I suggest 10:1 for US customers.

Keep in mind, if you end up stroking it, the camshaft selection will change.You can stay with a hydraulic, but it will be larger to suit the extra cubes. It will produce over 500hp then.'

Some great info here, which I thought worth sharing, as I think AFD are one of the most experienced 351 Cleveland head and engine builders these days, and Cleveland info is not so readily available as Windsor info.

[wilf]

Those 2V closed chamber heads with their wide squish area are very good at fending off detonation.

You have to love an engine that went out of production nearly 25 years ago after only a short production life and you can still get new performance bits for it!

[dingocooke]

Know what you mean Wilf, for an engine that only had a three year production life stateside (1970-1973 circa 3 1/2 million engines produced) it is an incredible design, loads of torque, just loves to rev.
(Mind you, it had a further 10 years in Australia from 1973-1983 ish)

[ldtopham]

Thanks for sharing Steve The best bit for me is the sound, it's so different from most other small blocks, almost big block but without the same level of gruffness! Did you get a price to UK or would you buy from a reseller?

[dingocooke]

Yep hes spot on is Dave at AFD!! his heads are USD$2100 assembled delivered, which is a lot better than the resellers price.

[Martyn-ak427]

Guys,

I know the Windsor & Cleveland have their variances but I am running a XE284H bumpstick, Scat crank & H beam rods & am very impressed with the hardware. I did alot of research into cams & the general concensus was the XE284H will not choke a 393ci stroker but adversely will allow the car to be drivable as it is not overly aggressive. For information I am also running a CR of 10.5:1 & using a Edelbrock RPM Airgap manifold however this does sit very high in the engine bay & only just allows the bonnet to be closed.

Regards,
Martyn

[Cobmonster]

I am very impressed with the 65000rpm that must be warp speed.