Stroker 445 with 428CJ exhaust - worthwhile?

[cheeser]

I’m thinking of having the 390 in my 68 Cougar rebuilt in a few years with a stroker kit and Trick Flow heads, but keeping the 428CJ exhaust manifolds (installed by original owner) for appearance and clearance.

I’m curious what type of a power hit I would see using the CJ exhaust vs installing headers.

I understand the need for headers to make max power, but headers in these cars seems to be a pain.  I live in Denver and already see a performance hit due to altitude, but my goal would be around 425hp, but more wouldn’t hurt.

Just exploring options for now, before getting serious in a few years.

[jayb]

On the 390 stroker engine chronicled in my book, the different headers I tested ran from 485HP to 500HP.  The same engine with the 428CJ manifolds was just shy of 460 HP.  So I think you could probably figure on a 30-40 HP loss if you stuck with the CJ manifolds.

[1968galaxie]

Sounds like a cool project.
You may want to contact Brent Lykins here regarding a custom camshaft for that particular application.
I am sure he has a few ideas regarding camshaft duration split when using CJ exhaust manifolds.
My initial thoughts would be more of a duration split as well as opening the exhaust valve a little earlier.
Perhaps Brent will chime in.

Cheers

[Barry_R]

Recently dyne's one similar.  I can verify that +/-30-40 HP loss with the manifolds.  We have done several strokers with manifolds for folks looking for the power and torque gains while retaining that concourse cosmetic appearance.

[aj]

One way of looking at it is:  To gain 30-40 hp out of a 390,  a guy can add 55 cubic inches OR add nice set of headers.   

[GerryP]

I removed the Hooker Super Comps from my Fairlane and put CJ manifolds on it.  Yes, I know the manifolds will be down on power.  But I'm not class racing the car, so the simplicity of the manifolds overrode the power difference.  It still will flywheel the tires, so it appears I'm making enough power to get some tickets.

[cheeser]

So I haven’t heard anyone saying I’m nuts so far :-).  With the stroker kits and nice heads out there now, I assumed decent power could be obtained, while keeping an outwardly stockish appearance.

My last adventure with an FE engine was in High School in the 80.  I had a 64 Galaxy with 4 spd and blown 390.  I found a wrecked 62 Galaxie with a freshened 406 tripower.  My auto shop teacher let me transplant the 406 into my 64...had a lot of fun, but it rusted out being WI and I left to join the military.  I sold the motor about 15 years ago as I thought I’d never have another FE, but here I am again.  I had a blown Coyote in my 13 Mustang w 609 hp for a few years...extremely fun and smooth, but sold it for the Cougar.

The existing 390 runs decent now, but it has the stock 2 barrel.  Until I can convince the spouse on this, I was going to put a Blue Thunder 427MR intake on and 4 barrel in the interim...later this summer once I work the rest of the Cougar gremlins out.

I have been watching Barry and Lykins, and this forum just to see what is out there.  I am not aware of any knowledgeable FE builders in the Denver area, thus another reason for me to stalk this forum.

[plovett]

Is there any practical, economical, and worthwhile porting process that can be applied to factory iron exhaust manifolds?  Sand blasting?  Acid porting?   I understand Extrude Honing is very expensive for very small gains.

paul

[cjshaker]

There are a number of 'shorty' tube headers that are being produced for the FE now. Since you're not in a big hurry, it may be worth some time researching to find out if any of them fit the Mustang/Cougar engine bay. I'd imagine that a shorty would cut that HP loss in half and still be easy to install without most of the interference issues associated with long tube headers.

[Skeeter65]

Doesn’t Sanderson make shorty headers for the FE that will fit the Mustang and Cougar? The build from the OP sounds a lot like what I’m doing with mine but it’s going in my ‘67 S Code Mustang coupe.

[cheeser]

There are a number of 'shorty' tube headers that are being produced for the FE now. Since you're not in a big hurry, it may be worth some time researching to find out if any of them fit the Mustang/Cougar engine bay. I'd imagine that a shorty would cut that HP loss in half and still be easy to install without most of the interference issues associated with long tube headers.

I actually thought about “shorty” headers over the winter, but didn’t find anything for my application in a Cougar.

I considered custom, but assumed prices escalate fairly fast.  I don’t mind somewhat of a premium if they were available though. 

I currently have a very slight exhaust leak at the manifold as it appears the shop used a gasket when it was rebuilt back in 2008, and the CJ manifolds were installed. I’m probably going to have to address that at some point...not looking forward to it as I don’t have a lift.

[turbohunter]

Just a quick word on the Sanderson shorties.
I have a set that came on my wagon. By far the biggest piles I’ve ever had. I have had them off my wagon at least five times to weld them up. I’ve reflattened the flange twice and welded up many cracks. It’s like they used sub par metal that crystallized when they welded them originally.
There is one leak in the middle of the collector I can’t get a torch on. Tick tick tick when I lay on it.
They are horrible.
Why haven’t I replaced them yet? Waiting for new heads and just trying to get by.
Your experience my vary but beware. I don’t like being negative but these deserve it.

[70bosscat]

FPA tri-y perhaps?

[Cyclone03]

Just a quick word on the Sanderson shorties.
I have a set that came on my wagon. By far the biggest piles I’ve ever had. I have had them off my wagon at least five times to weld them up. I’ve reflattened the flange twice and welded up many cracks. It’s like they used sub par metal that crystallized when they welded them originally.
There is one leak in the middle of the collector I can’t get a torch on. Tick tick tick when I lay on it.
They are horrible.
Why haven’t I replaced them yet? Waiting for new heads and just trying to get by.
Your experience my vary but beware. I don’t like being negative but these deserve it.

If your headers are stainless and your putting a torch to them they will crack.

[turbohunter]

Not stainless

By “torch” I meant a mig or tig gun/torch.