website:www.grannysspeedshop.com
289/302/351/5.0
The purpose of this guide is to lay down the necessary tasks in an orderly fashion, to hopefully minimize the
time and effort required to pull off a successful COMPLETE conversion.
Often times projects such as this are undertaken without a full understanding of
what is involved. Hopefully, this summary of the steps necessary will provide individuals
with the insight necessary to evaluate their own abilities, and help them come up with
accurate estimates for both time and cost. Most hot rodder types will not need these instructions,
but if they encounter a problem at some point, it's nice to know that helpful information is a close as their computer.
This is a very easy swap that can be executed successfully by the average shade tree mechanic. No special mechanical skills or tools are required.
Many, if not most of the steps described here, are the same regardless of the engine choice. Injected engines such as the TBI, TPI, Vortec and LT1 will differ mostly with regards to electrical connections and fuel system plumbing. The main mechanical components and basic proceedures are generally the same.
If you would like more info on completing a smog legal conversion in California, CLICK HERE
Additions and corrections to this guide are encouraged, and will hopefully result in an evolutionary process that will eventually include EVERY detail required, right down to the wrench type, sizes, torque specifications and parts required to carry out each individual step.
Effects On Maintenence & Reliability...
...If you already own a 1st gen RX-7, then you already know about the rotary’s
maintenance requirements, have probably heard stories about dealer service
departments that lack proper training on rotary engines, and chances are, your beautiful
RX-7 is probably on it’s 2nd or 3rd engine by now. The RX-7 has not
been sold in the US since 1995, and replacement parts are getting scarce.
The Ford engine, on the other hand, is a very common engine. Most any person with automotive experience has worked on one, and a large
factory trained network of technicians exist from coast to coast. The modern Ford
engine routinely goes 100k between tune-ups, and replacement parts are among the
cheapest and most common.
Effects On Performance...
...As you might suspect, the switch to a V-8 powerplant has an effect on
performance too. The additional low-end torque makes the RX-7 very easy to drive, and
is available throughout the RPM range. No longer will you have to excessively slip the
clutch at a stop light to keep from killing the engine. No longer do you have to downshift,
wait for your RPMs to come up (or boost to build) to pass a car. No longer will you live
in constant fear of the dreaded carbon lock. With the V-8, your power is always available.
If and when it comes time for an upgrade, things can really get interesting. Simple
$100. modifications can result in 15-20hp increases, while spending a mere $4-5000. can
get you up to around 500hp level. We are seeing low to mid 13 second 1/4mi times from
mild smog legal engines with around 300-325hp, which is better than the high 17 second
times that were possible with your RX-7’s stock rotary engine.
Effects On Weight, Balance, and Handling...
...This is where you probably expected there to be a downside. People have
probably told you that your handling and perfect weight distribution will be ruined with
the addition of that big, heavy, american V-8. Just ask yourself if any of those so-called
experts you have been talking to have any actual experience with piston-powered RX-7s.
We’ve got the numbers to prove all those bystanders and spectators are just
that....bystanders and spectators.
Skills Required...
...If you have a good grasp of things mechanical, do all your own automotive
maintenance, have a good selection of tools and know how to use them, you are probably
qualified to perform this swap.
Estimating Time For Completion...
...We have broken the conversion process down into smaller steps (links listed below). This allows the person actually doing the conversion to
estimate the time he should allow depending on his abilities and resources.
2....Considerations & Requirements....
4....Engine / Transmission Installation....
5....Exhaust / Throttle Cable / Accessory Drive / Pulleys....
6....Cooling / Fuel Systems....
7....RX-7 Wiring Harness Connector ID and Circuit Locations....
8....Electrical System Modifications By Circuit....