6066 (1960-1966) GMC Truck Club

6066 (1960-1966) GMC Truck Club (https://6066gmcclub.com/index.php)
-   GMC V6 and V12 Engines (https://6066gmcclub.com/forumdisplay.php?f=9)
-   -   305e Holley 500 swap question (https://6066gmcclub.com/showthread.php?t=50616)

jerrspud May 9th, 2019 05:00 PM

305e Holley 500 swap question
 
2 Attachment(s)
Hello,

I was able to get the info about the carb type and adapter needed for the swap, but there is some basic info that I'm missing. I'm normally an all stock guy, so I'm a but stumped with modifications :eek:
http://6066gmcguy.com/holley.html


1. Do I put the mr. gasket adapter on top of the original spacer or do I remove the original spacer?
https://6066gmcclub.com/attachment.p...1&d=1557417129

2. Linkage: I don't see an easy way to get the original throttle linkage to fit. Is there an adapter I need for the carb or different linkage?
https://6066gmcclub.com/attachment.p...1&d=1557417158

thank you
Jerr

63gmc4x4 May 9th, 2019 06:23 PM

Re: 305e Holley 500 swap question
 
remove the factory spacer and studs, your current accel rod should fit on the bigger hole just fine you may needs to unthread it for more legnth

jerrspud May 9th, 2019 06:58 PM

Re: 305e Holley 500 swap question
 
awesome.... that sounds simple.... thank you!


jerr

jagarra May 9th, 2019 11:39 PM

Re: 305e Holley 500 swap question
 
Now if you bought a Holley with a manual choke you will find the cable isn't long enough with the new carburetor. On the right side of your column there is a block off plug in the dash for something not installed, I moved the choke cable assembly from the left side to that side and had enough length.

bigblockv6 May 10th, 2019 03:55 AM

Re: 305e Holley 500 swap question
 
On my 68 the choke cable was actually long enough without requiring to move the cable to the right side of the cluster.

jbgroby May 10th, 2019 02:11 PM

Re: 305e Holley 500 swap question
 
2 Attachment(s)
Because I had a '60, I had to create this linkage. Works perfect.

jerrspud May 12th, 2019 05:01 PM

Re: 305e Holley 500 swap question
 
Quote:

Originally Posted by jbgroby (Post 70974)
Because I had a '60, I had to create this linkage. Works perfect.

what's the number for that spring bracket? I don't know what it's called.

jerrspud May 12th, 2019 05:01 PM

Re: 305e Holley 500 swap question
 
yes... I have manual choke. I have to buy a new cable so I hope it comes long and I can trim it down.

i found the adjustable end of the throttle rod and it seems like it will work well.

truck stated really well with new carb. I assume I'll have to do some tuning to get it to be drivable, and I need to hook up the vacuum advance to the carb as well.

jrmunn May 14th, 2019 03:23 AM

Re: 305e Holley 500 swap question
 
Jerrspud,

Others might disagree (and probably will), I have found that my 305e engine runs a little rich with the stock Holley 500 (which does help the engine start easier), but I have not taken the time to play around with it. Because the choke on the 500 also moves the throttle on the other side of the carburetor, it is difficult to pull out the replacement choke and longer cable (from NAPA) that I am using. This is made easier by pushing down on the throttle pedal. But converting to the 500 is well worth the effort and makes the engine run much better at higher RPMs.

JRMunn

bigblockv6 May 14th, 2019 04:21 AM

Re: 305e Holley 500 swap question
 
You're right the 305 V6 may run rich with the Holley 500 but it's an easy fix by just installing leaner jets.:upyes:


All times are GMT +1. The time now is 06:26 PM.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.