Figured out how to make external ESC work with a 7427

[CamaroDude85]

I figured out how to make a external ESC work with a 7427. I tried wiring it into B7 like I've seen in the conversion write ups but that didn't work, it would register knock counts like crazy. I got to thinking and figured the ESC mounted on the memcal and external ESC probably worked the same. So I cut the memcal ESC off, put a 4k ohm resistor between cal 29 and 31 to keep from throwing code 43 and soldered a wire with a spade terminal on one end to cal 32(esc output) of the memcal. Plugged the black wire that originally hooked to b7(esc output/knock sensor) on my 8063 onto my little pigtail coming off the memcal and bingo it works! I've started to get more aggressive with my spark advance as the stock table for a 305tbi is pretty weak. So far I'm at a max of 20 BTDC at wot with the main table plus 3.2 of PE spark and it has really woke up the engine. No knock counts to speak of other than a single one here and there which I assume is not actual knock because in 15 minutes of fairly hard driving with some wot mixed in I only got 5 total knock counts. To pretty it up some I'm gonna cut a slot in the metal PROM cover and put a grommet on it so I can still get easy access to the PROM.

[PJG1173]

Interesting have any PICs?

[CamaroDude85]

Gotta get the camera charged up, but I'll try and post some up sometime this evening.

[EagleMark]

Double check knock counts with engine running and scanning and hit block with hammer, look for knock counts.

[CamaroDude85]

Good idea about hitting the block I did that and each time I hit it, it would register a knock count. Here's the pictures you'll have to excuse my soldering and melting the dip socket some lol. I've got the grommet fitting pretty tight to act as a strain relief. Oh yeah I forgot that I didn't have a 4k resistor so I used a 100 ohm and a 3k9 to get 4k forgot all about that until I looked at the picture
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[RobertISaar]

the 3.9K alone would have been fine, since the knock sensor is actually 3900 ohms when not being rattled.

[CDeeZ]

This is cool. Did you do the ESC this way for any particular reason, or just to see if it could be done?

[CamaroDude85]

Only reason I did it like that was I couldn't find a 7427 from a V8 and from what I've read the V6 ESC doesn't work to well with a V8. I didn't intend on running any of the knock stuff at first anyways but then I got bored and figured it'd be good to have in the data stream. For what ever reason it's kinda rare to come across anything later model Chevy V8 at the affordable pick a part here, there will be plenty of Ford 4.6's but few if any Chevy's and if there is it's pretty well picked over before it gets set out for the customers. There is another pick a part here in town with plenty of later model stuff but you can almost buy it new for what they want for it