440Source.com Stealth heads

[Moparman01]

Quick question, planning a 440 build right now, want to stay looking fairly stock, will the 440source.com Stealth heads work with stock "HP" exhuast manifolds with out any modifications? If not, would the HP manifolds need to be port matched? I'm not concerned about the performance loss between manifolds and headers, i need new heads anyways so i'd like to go aluminum and keep my stock exhuast in place. Thanks! 

[BSB67]

".....will the 440source.com Stealth heads work with stock "HP" exhaust manifolds with out any modifications?"   Yes

"If not, would the HP manifolds need to be port matched?"  No, but most of the guys looking for some hp improvement at least port match the exhaust manifold window, or even make it slightly larger.

A professional high performance valve grind and bowl work will add measurable power.

Measure where your piston is relative to the deck @ TDC.  If your compression ratio is low, you may consider milling the heads to put some ratio back in.

Exhaust manifold engines are a little finicky about cam timing.  Consult with someone experienced in specing cams in exhaust manifold applications.

These are just some thoughts.  If your budget allows, this will be a good time to add some decent power back.

[AKcharger]

I have cast iron HP's on my 440source heads, They work fine. One suggestion is get the HP valve retainers, I heard one guy dropped a valve and the ones that come stock are IMO substandard. I changed mine out after they were on the car and it cost me some $$$

[Moparman01]

I have cast iron HP's on my 440source heads, They work fine. One suggestion is get the HP valve retainers, I heard one guy dropped a valve and the ones that come stock are IMO substandard. I changed mine out after they were on the car and it cost me some $$$

Thanks for the info! I'm going to the engine shop today to finalize the plan for my new motor, i'll be sure to let him know about the valve retainers if he doesn't already know. Haven't looked but is there an option for the HP retainers when you order the heads??

[bobs66440]

I have cast iron HP's on my 440source heads, They work fine. One suggestion is get the HP valve retainers, I heard one guy dropped a valve and the ones that come stock are IMO substandard. I changed mine out after they were on the car and it cost me some $$$

Thanks for the info! I'm going to the engine shop today to finalize the plan for my new motor, i'll be sure to let him know about the valve retainers if he doesn't already know. Haven't looked but is there an option for the HP retainers when you order the heads??

I just bought a new set and they came with Comp 7* locks. They may have had issues in the past but I think they are installing these now as a result? They recommend 10* locks if you are running a big cam and high rpm.

[Moparman01]

Ok, well that works out good then, i'm not planning on any big cam or high RPMS, just a good street/cruiser motor!