Q-Jet to Holley
NoRiceHere01
11-02-2006, 10:24 PM
Hey guys i recently bought an 86 Z28 from a friend and it currently has the stock quadrajet carb on it. i like the q-jet, but these year cars got the stupid half electronic carbs that dont work right without everything plugged in and operating.i have no cat and an aftermarket temp guage, which naturally removed the port for the old temp guage to plug in.because all this crap is no longer connected the mixture is never right, its always too rich.at any rate, i have a 4V holley single pump, single fuel inlet that im gonna put on. my question is how many of u have done this, because im curious what i need to perform the swap.the fuel line connects in a different spot and im not sure the throttle linkage will bolt right on.i can figure it out when i take it apart and find out exactly what i got, but any info i can get ahead of time would really help. also theres a strange whistle coming from the dash behind the guage cluster that im pretty positive is a damn vacuum leak.has anyone had this happen to theirs? and if so what was it?
wrightz28
11-03-2006, 10:08 AM
If it's constantly rich, the coolant temp sensor may not be any good or disconnected.
NoRiceHere01
11-04-2006, 11:02 AM
yes i know the sensor isnt connected.i have an aftermarket temp guage, so the fitting with the plug is gone from the thermostat housing.i dont think it matters tho cuz im gonna put the holley on anyway
silicon212
11-04-2006, 11:33 AM
You need to replace the distributor with one that has mechanical advance (vacuum/centrifugal) or else your engine might as well power a Yugo and your fuel economy will be similar to that of an EMD SD40-2 diesel-electric locomotive.
capriceowns
11-04-2006, 12:14 PM
and make sure it has the kickdown for your trans. I know holley sells brackets for Ford and GM kickdowns.
Morley
11-04-2006, 07:25 PM
yes i know the sensor isnt connected.i have an aftermarket temp guage, so the fitting with the plug is gone from the thermostat housing.i dont think it matters tho cuz im gonna put the holley on anyway
You are thinking of the temp SENDER, the sensor is something different, its only purpose is to send temp readings to the computer. The sensor should be in the T stat housing and the sender should be in the driver side head...someone may have put the aftermarket sender in the wrong place.
Personally I HATE holley carbs, never had one or worked on one that wasn't a total pain. The Q jets have more parts and take a bit of tinkering to get it set up, but once it is set it won't require constant "tweaking" like a holley.
You are thinking of the temp SENDER, the sensor is something different, its only purpose is to send temp readings to the computer. The sensor should be in the T stat housing and the sender should be in the driver side head...someone may have put the aftermarket sender in the wrong place.
Personally I HATE holley carbs, never had one or worked on one that wasn't a total pain. The Q jets have more parts and take a bit of tinkering to get it set up, but once it is set it won't require constant "tweaking" like a holley.
NoRiceHere01
11-05-2006, 12:01 PM
what kind of advance does it have now? electronic?
NoRiceHere01
11-05-2006, 12:02 PM
o and dont worry about the kickdown. someone already has it disconnected from the q jet thats on there unfortunately.i know all about that
Whoaru99
11-06-2006, 08:38 AM
Well, maybe you should reconnect all that disconnected stuff and actually fix it, rather than cobble it up even more. The "fix-it" route might just be easier and probably would run better than the Holley anyway.
I had, for a few years, one of the Z28s with the HO L69 engine that had the "electronic" Q-jet. It ran pretty darn good from what I can remember.
I had, for a few years, one of the Z28s with the HO L69 engine that had the "electronic" Q-jet. It ran pretty darn good from what I can remember.
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