331 / 400 Horsepower Engine

Below is a list of frequently questions and concerns


What is the difference between the 331 and 347 Stroker Engine ?

There isn't a huge difference between the two engines.  The 331 has a 3.25 inch Stroke and the 347 has the 3.40 inch Stroke.  Horsepower numbers are very close to one another too. Many engineers say that the 331 has a longer life span due to a better bore to stroke ratio and perhaps better oil control. We've had success with both engines though.

What application vehicles would this engine work best with ?

The 331 stroker has the same outside shell as a 289 or 302. So this engine will work with a wide range of year, make and models. For instance Early to later model Mustangs, Kit Cars, Hot Rods & Trucks to name a few. We will match up the necessary components to your vehicles requirements. For Example a 1966 V8 Mustang will require a different oil pan, flwheel, harmonic balancer and Water Pump then a 1984 Ford V8 Mustang!

What about idle quality and will I have enough vacuum to run my accessories ?

This is a pretty common question. We would rate this engine as fair with a classic muscle car sound. A little bit of a lumpy sound to it but it's not going to shake you to death! Usual idle is around 1000-1100 RPMs. This will depend upon other factors.  Vacuum will be fine for running accessories like Air conditioning, Power Steering and Power Brakes.

What other engine will this engine interchange with ?

The 289 and of course another 302 will interchange very easily with this motor. Earlier applications like a 221 or 260 can work with some minor modifications. 4 and 6 cylinder conversions also a possibility. Speak to one of our sales / techs on this.

What octane gas does this engine require ?

 All our engines will run on good quality pump gas. This engines compression is @ 10 to 1 so it can run very comfortably within 91 to 92 octane range.

What is the Redline that this engine be taken up to ?

This particular engine we would suggest RPMs be kept to under 6000 RPMs.

What is the Power Range of the engine ?

2000 thru to 6000 RPMs  Making this great a very broad and streetable setup!

Will my stock Transmission work with this engine ?

In most cases the answer to this questions is Yes. A great deal of our customers re-use or freshen up their existing transmission.  For mostly cruising around and / or laying down some rubber once in a while the factory transmission will hold up fine. Those of you who are doing holeshots and abusing the crap out of your car (You know who you are!) you may want to step things up. We may be able to give you some ideas or just talk to a Tranny guy. If your without a transmission and looking for advice on which to choose from. A heavier duty C4, C6 or a modified AOD Automatic Transmission will do the trick. For Manual  Transmissions there's a lot available like the popular Tremec 5 or 6 speeds.

Will I need a higher Stall speed torque Converter to compliment this engine ?

This question applies to Automatic Transmissions only. It's usually recommended. Depending upon the use of the vehicle on the street or the track then perhaps one step up on the factory stall speed will improve acceleration off the line. Other factors like the weight, gearing , tire size can come into play too. Speak to a Transmission expert on this. 

Will it be required to change out my Rear End & What Rear end and Gearing is recommended with this engine ?

Two part question. Many of our customers past and present have used their existing gears and have been pleased with the results. But this again comes into play what you want to do with the vehicle. For the most part a rear end gear ratio of 3.55 up towards 4.11 would be ideal. The RPM range that you drive in most will determine what's best for your situation.  Speak with a Rear end expert for some assistance on this matter.

Can I use my existing Exhaust manifolds?  Are Headers required and what diameter should be used ?

Yes you can bolt up your existing exhaust manifolds and in most if not all occasions that will be a direct fit. But as you may know an engine acts like a air pump the more efficient the air and fuel is delivered  in and exits out the better and more responsive it will become. The Edelbrock Aluminum Cylinder Heads on this engine have the same factory bolt pattern to work with pretty much any standard Header. A general idea in Header size would fall in place of 1" 5/8 to 1" 3/4.

What size Radiator is recommended ?

Last but not least!  This engine or any other engine we offer needs to run cool to expect long term results out of it. A used / older radiator that has been sitting around is not worth cleaning and reusing . A new 3 or 4 core Radiator is a cheap investment compared to an overheated $6,000.00 engine!  It's worth the investment to spend a couple of hundred bucks to get a new radiator. Pay a little now or pay Later philosophy. There's plenty of good Radiator companies out there 


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