A: I have to say their customer support totally lacks. One of our customers spent $5,000 on Holley stuff, but when he tried to get tech support, they ignored him for 3 months, so he just returned it all new in the box! (Can you say ouch?) You'd be far better off with the GM TBI setup which has LOTS of support online and by phone. 670 would be great for racing, but would suck at the pump and idling the Pro-Jection system tends to overfuel no matter where you set it. That's been the experience of many with the V8 setup at least till they got the O2 sensor setup and plugged off all the AIR system. (Cam Brown's Flying Eagle did that as well as Don Hansen of the FSJ list and Garrison St Clair {MHRIP} of the strokers list in Mexico) Others poke and prod and keep tweaking the system and change the MAP programs to match what they need from it. (Several suffered total system failure during the Ouray FSJ Invasion of '02) From: Tom Jennings <tomj@xxxxxxx> To: AMC List <mail@xxxxxxxxxxxx> Subject: Holley Pro-Jection for a 258? Message-ID: <20050418150242.D651@localhost> I tried calling Holley, but they don't seem to have application support... I may get rid of my tax return with a Holley Pro-Ject system for my Hornet. (No LP conversion at this time; I want on-road fast!) Holley makes one kit, 501-12, that is a 300cfm bolt-on for the Jeep 258. This sounds like the correct kit for me. However at least one person is saying I should get the 670 CFM kit instead. There's no real difference in price, and both are 2-bbl replacements. Will the 670 work OK at low speeds/low CFM? Does this sound right? Are holley CFM ratings conservative or bragging? I'm looking for a used one, if anyone has one, digital only.