The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-02-2005, 11:04 AM   #1
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Pertronix Ignitor Problems...

Hey Everybody! First time on the site and I'm loving it! I have a '69 GMC 1-Ton Longhorn, SM465, 104,000 original miles. I just dropped in a new 350 w/ZZ4 lo-compression heads, big lopey cam, holly carb, and the latest upgrade was the swap from good ole points to the Pertronix Ignitor II and a new Flamethrower II coil. I am apparently the only person on the face of the earth whose performance has gone DOWN (the truck's performance, not mine!) by swapping out the points! Pertronix has no ideas, nor has anybody else I've asked. The cold starts are worse, it hesitates in the lower RPM's, and the mileage is worse than it already was. The plugs, wires, cap and rotor are fairly new, all the clearances for the Ignitor module meet their spec's... I'm lost. Can anybody help?
soundspecilist is offline   Reply With Quote
Old 11-02-2005, 11:13 AM   #2
jhow66
Registered User
 
jhow66's Avatar
 
Join Date: Jun 2002
Location: Knoxville Tenn.
Posts: 3,058
Re: Pertronix Ignitor Problems...

Did you have the Dist. out? Is the clearence the same all the way around? Is the dist. out a notch and made up by moving the dist. back or forward? Have you got # 5 & 7 plug wires crossed?
__________________
56 Chevy Bel-Air 2dr. HT (purchased new)
71 Chevy Cheyenne SWB PU (502HO)
65 GMC short bed step--work in progress and my gofer
jhow66 is offline   Reply With Quote
Old 11-02-2005, 11:41 AM   #3
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Re: Pertronix Ignitor Problems...

1) Yes.
2) Not Sure, but I'll check this weekend when I pull it again.
3) Distributor is in the correct position. I've learned from my mistakes on that one! (blown muffler from backfire, carb fire, fun stuff!)
4) 5 & 7 are correct.
A new stock distributor doesn't cost that much and the one in there is probably original. I'm thinking of buying a new one and seeing if that helps the issue. Thanks for the reply. I'll let you know what happens.
soundspecilist is offline   Reply With Quote
Old 11-02-2005, 11:53 AM   #4
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: Pertronix Ignitor Problems...

origal wiring in these trucks includes a resistor circuit//most changes require running a new wire to the dizzy for a full 12V supply
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 11-02-2005, 12:06 PM   #5
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Re: Pertronix Ignitor Problems...

I did confirm that there was 12 volts being delivered to the coil. I haven't found a resistor circuit yet (nothing on the firewall or obviously displayed), but it could be hidden. I'll check it out.
soundspecilist is offline   Reply With Quote
Old 11-02-2005, 01:17 PM   #6
72 longhorn BB
Registered User
 
72 longhorn BB's Avatar
 
Join Date: Jan 2000
Location: Michigan
Posts: 312
Re: Pertronix Ignitor Problems...

I put a used GM HEI in my rig and when I did, It was recommended that I get the thing curved for my engine.

Never had a problem with it, but was told I could expect those kinds of problems if it wasn't checked out and matched to the setup I had.
__________________
Chuck

1972 C-20 Longhorn
402 BB .030" over (409?), curved HEI,
RV cam, quadrajet, dual 3" exhaust, TH 400 ported w/shift kit

1999 K1500 Suburban (old style)
5.7L Vortec
4L60E

"No matter where you go, ........ there you are"
72 longhorn BB is offline   Reply With Quote
Old 11-02-2005, 01:34 PM   #7
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Re: Pertronix Ignitor Problems...

I hadn't thought about recurving it. That's a good idea. Thanks!

Since you're a fellow Longhorn owner, any idea where I can buy a pre-fab bedwood kit? All I can find are either short or long bed, but no Longhorn. Can you help?
soundspecilist is offline   Reply With Quote
Old 11-02-2005, 01:39 PM   #8
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: Pertronix Ignitor Problems...

the resistor is the original wiring in the truck//not a seperate resistor//if you peel the wiring harness that goes accross the firewall the dizzy wire will go into a thicker wire thats lookin like it's wrappedv in old electricaltape that's the resistor circuit
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 11-03-2005, 02:45 AM   #9
tomatocity
Registered User
 
tomatocity's Avatar
 
Join Date: Jun 2005
Location: Sacramento CA
Posts: 1,255
Re: Pertronix Ignitor Problems...

Quote:
Originally Posted by cdowns
the resistor is the original wiring in the truck//not a seperate resistor//if you peel the wiring harness that goes accross the firewall the dizzy wire will go into a thicker wire thats lookin like it's wrappedv in old electricaltape that's the resistor circuit
I agree. Should be easy to test using a a new wire.
__________________
Got bored, sold everthing. Got bored, looking for a 1960-66 C-10. Want to build my last truck.
tomatocity is offline   Reply With Quote
Old 11-03-2005, 08:35 AM   #10
72 longhorn BB
Registered User
 
72 longhorn BB's Avatar
 
Join Date: Jan 2000
Location: Michigan
Posts: 312
Re: Pertronix Ignitor Problems...

I guess I'm a little confused - did you hook you HEI up to the existing wire that went to the old distributer?

If you did, thats' wrong. You need to go to the fire wall connector and remove the pin from the connector and replace the whole wire and terminal (buy them at Pep Boys) to the dizzy, regardless of what you measured at the wire. That wire IS the resistor and will never supply enough voltage to make your HEI work right.

After that, try recurving it if you still have problems
__________________
Chuck

1972 C-20 Longhorn
402 BB .030" over (409?), curved HEI,
RV cam, quadrajet, dual 3" exhaust, TH 400 ported w/shift kit

1999 K1500 Suburban (old style)
5.7L Vortec
4L60E

"No matter where you go, ........ there you are"
72 longhorn BB is offline   Reply With Quote
Old 11-03-2005, 10:25 AM   #11
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Re: Pertronix Ignitor Problems...

I didn't hook up to the original wire that went to the DISTRIBUTOR. The Ignitor came with its own lead for that. The only original wire is the one going to the positive side of the coil (which is a new Flamethrower). So are you saying that the Pos wire going to the COIL is the resistor lead? Sorry if I'm a little dense, but I want to make sure this is clear as mud before I get in there and start replacing wires.
__________________
'69 GMC C3500 1-Ton, Longhorn, SM465, built 350,
soundspecilist is offline   Reply With Quote
Old 11-03-2005, 10:32 AM   #12
Scrubby
Check out GMTrucks.org
 
Join Date: Sep 2003
Location: Boise, Id
Posts: 284
Re: Pertronix Ignitor Problems...

He shouldn't need to recurve it. He only went from points to a pertronix. I'm guessing that he didn't touch the weights or springs, so no need for a recurve.

I would run a new wire from a 12 volt source and see what that does.
Scrubby is offline   Reply With Quote
Old 11-03-2005, 10:40 AM   #13
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Re: Pertronix Ignitor Problems...

I just filled up and got 10 MPG, mostly highway miles! I was getting 11 - 12 before the Pertronix. This weekend I'm going to tackle it and see what I can do. I'll update y'all after that. Thanks to everybody for the advise. Hopefully it will pay off!
__________________
'69 GMC C3500 1-Ton, Longhorn, SM465, built 350,
soundspecilist is offline   Reply With Quote
Old 11-03-2005, 10:52 AM   #14
jhow66
Registered User
 
jhow66's Avatar
 
Join Date: Jun 2002
Location: Knoxville Tenn.
Posts: 3,058
Re: Pertronix Ignitor Problems...

Here is the way it should hook up:
Attached Images
 
__________________
56 Chevy Bel-Air 2dr. HT (purchased new)
71 Chevy Cheyenne SWB PU (502HO)
65 GMC short bed step--work in progress and my gofer
jhow66 is offline   Reply With Quote
Old 11-03-2005, 10:59 AM   #15
soundspecilist
Registered User
 
Join Date: Nov 2005
Location: Los Angeles, CA
Posts: 15
Re: Pertronix Ignitor Problems...

That is awesome! Thanks for doing that! I just printed it. I may tackle this tonight!
__________________
'69 GMC C3500 1-Ton, Longhorn, SM465, built 350,

Last edited by soundspecilist; 11-03-2005 at 10:59 AM.
soundspecilist is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:02 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com