Tom Langdon's web site has an HEI unit for a 230. I guess a junk yard is an option also. Tom checks out each unit for proper performance in fact on the bottom of the units you can see a hand written "OK" in white lettering. He stands by his products and will help with any technical questions via email or phone. In tech. articles on this site a guy converted a dizzy with a file and another guy said it was too much work and to buy a Langdon's? Its all good just personal choice.....T/C Steve