Sandrail RX-7 Mazda Conversion FAQ

Mazda RX-7 Sandrail Conversion Frequently Asked Questions

Copyright (c) 2003-2004 Scott M. Baker.Note: Please do not plagiarize this page! You are welcome to place a link to this page from your site, but please do not copy the contents (or pictures) from this site to your website without our express written permission (contact: sandrail@smbaker.com).

You can ask me a question at sandrail@smbaker.com, and I’ll answer you to the best of my ability, and probably place the answer up here as well. I don’t know everything, but I will try to answer your question as to how it applied to my conversion experience.

Can I gravity feed my fuel into the stock RX-7 carb?

I don’t think so. Everyone I’ve talked to has told me that the stock RX-7 carb is very sensitive to fuel pressure. Too high pressure will cause the engine to run to rich. Too low pressure (i.e. gravity feed) will probably cause it to run too lean. 

1. Do I really need an engine from an Automatic RX-7 with the conterweight?Yes. The reason for this is that you will be using a modified non-counterweighted VW flyweel from the kennedy conversion kit.
2. Where do I get the pilot bushing from to mate the VW transaxle input shaft to the RX-7 output shaft?Mine came with the kennedy conversion kit. It’s a little bronze-looking bushing. If you knew the right ID/OD (which I don’t), then you could probably pick one up somewhere. Call the kennedy people — they might know.
3. How do you connect aftermarket gauges to the RX-7 engine?Mazdatrix and Racing Beat sell an adapter kit that lets you connect aftermarket oil presure and temp senders. You can also make an adapter by drilling & tapping an old mazda-style oil pressure sender. See the instrument-panel or step-by-step links to the left for more details.
4. How much more does a 12A engine weigh that a stock VW engine?Yes. The reason for this is that you will be using a modified non-counterweighted VW flyweel from the kennedy conversion kit.A reference at http://home.att.net/~marksmoore/Weights.htm lists the following weights:
   Mazda 12A: 348 lb
   VW Flat 4 air cooled: 215 lb

   You should also take into consideration additional weight from radiator, oil cooler, etc.

5. Under construction….

Questions / Comments / Etc — email me at sandrail@smbaker.com