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Old 01-03-2011, 11:24 AM   #126
motornut
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Re: Improve mileage 350 with Quadrajet

too much water and it gets slushy in the rad,and driving, it would freeze up worse trying to thin out, to go threw the rad,would blow the hose hopefully first
not sure how cold it is there but in the morning or when it hasn't been driven take off the cap and see if it's fluid or slushy
of course one day it's -5 it's ok but
then may drop to like -25 or-30 and thats gona be a problem
but in the pics in a couple of drops on the belt it looks like bits of rust,sludge?
it looks to have material in the drops
it should be clear drops like water but green or red
but it could have been rust bits on your fingers working on it
i also thought the red was for newer stuff
and can't be mixed
then the bucket and the look inside intake same non clear fluid worries me
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Old 01-03-2011, 11:40 AM   #127
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Re: Improve mileage 350 with Quadrajet

copied from another source
but look it up


I own a 2006 Chevy Impala with a 3.5-liter V6 engine. The odometer is at 25,000 miles and the coolant has never been changed. The other day when I checked the overflow tank the coolant was low so I added a gallon of green anti freeze to the tank. I told my mechanic this and he said to have the system flushed immediately or trouble will crop up. Is this true?

Stanley from Reno, NV




Yes, get that cooling system flushed immediately or you are in for massive trouble (if it hasn’t already occurred)! Your car takes the coolant Dexcool. What you added is Ethylene Glycol, a chemical that is not compatible with Dexcool. Flush the system now before you end up with major engine failure.



This is one of those questions that I get after the fact and usually engine damage has already occurred. The green and orange coolants do not mix. There are some coolants that claim compatibility with Dexcool, but I would rather err conservatively and add what the system is supposed to take rather than take the gamble. Guard against major engine failure read on.

Can I add the green coolant to the orange stuff?
As I stated above, the two chemicals of Ethylene Glycol (green) and Dexcool (orange) are not compatible. When mixed together they form a gel-like substance that stops coolant flow and consequently the engine overheats.

What exactly happens when these coolants are mixed?
The coolants chemically react and form a gel rather than a liquid. The coolant stops flowing through the system, clogs up coolant passageways and water jackets, radiators, and heater cores. The water pump overheats and fails due to a lack of lubricant in the coolant. Head gaskets blow, heads warp, and the engine suffers major damage.

If I have Dexcool in my car can I leave it in for the life of the car?
GM suggests flushing Dexcool for the first time in the life of the car at 150,000 miles.

Here’s the skinny on Dexcool
Eleven years ago GM introduced an engine coolant called Dexcool. It’s supposed to last 5 years or 150,000 miles but there have been problems with this coolant. Cooling systems that use Dexcool exhibit more acid buildup and rust in the system when the coolant level gets low and oxygen is allowed to enter the system. The acid eats away at head gaskets and intake gaskets. Rust builds up in the system, inhibiting coolant flow, which causes overheating. Overall, numerous cooling system problems have been attributed to the use of this controversial product, although GM sternly stands behind it. There are class action suits against GM on this issue, but no settlements have been made to date.

So what are the guidelines on maintaining Dexcool?
Here’s the bottom line when it comes to cooling system maintenance. Whether you are running Dexcool (the orange stuff) or ethylene glycol (the green stuff), inspect the coolant level and the condition/protection of the coolant at every oil change. In addition, completely flush and refill the system every 2 years or 25,000 miles whichever comes first. These actions will avert the problems associated with Dexcool or any other coolant product.

When I check my engine coolant what do I look for?
Color, consistency, and smell.

Color
The color of healthy engine coolant is green (for ethylene glycol) or orange (for Dexcool). A rusty color indicates that the rust inhibitor in the coolant has broken down and it can no longer control rust and scale buildup. The system must be cleaned/flushed and a fresh 50/50 mix of coolant installed to restore integrity. A milky color indicates the presence of oil in the system. This is not good; it usually means that a head gasket, intake manifold, or transmission oil cooler is leaking oil or transmission fluid into the engine coolant. This is a deadly mix that will kill an engine or transmission in short order. Address the problem immediately!

Consistency
The engine coolant should feel slippery to the touch and smooth (like the engine oil). If it feels gritty, the coolant is dirty and should be flushed and replaced with a fresh 50/50 mix. If the coolant does not feel slippery then it has lost its lubricity (the lubricating and rust inhibiting agents have deteriorated) and the system is at risk for rust and scale buildup, as well as water pump wear.

Smell
Change the coolant if it smells burned. Also change the thermostat; it’s probably gone bad because it was exposed to overheating (or it caused the overheating). Overheating damages the bi-metallic spring that opens and closes the thermostat valve. Most importantly, find out what caused the system to overheat and repair it, or face major engine damage.
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Last edited by motornut; 01-03-2011 at 11:42 AM. Reason: The mix is wrong for colder climents but you get the idea
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Old 01-03-2011, 11:45 AM   #128
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Re: Improve mileage 350 with Quadrajet

this is what i'd wana see
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Old 01-03-2011, 02:47 PM   #129
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Re: Improve mileage 350 with Quadrajet

He Motornut,

thanks for all the info. I will for sure change and flush the cooling fluid. Just not sure yet if I will do that using coolant and some type of pump. or with a gardenhose and just clear water. I am afraid water will stay behind in the engine en cause for more rust after I flushed it and filled it with new coolant.

I probably wanna get a flush-kit as mentioned before. And probably wanna get a big tub like this for under the car to catch all the fluid while flushing:

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Old 01-04-2011, 10:42 AM   #130
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Re: Improve mileage 350 with Quadrajet

you do use some water mixing it
unless you get the premix stuff but i prefer to topoff with the pure
keeping it in the upper 60-70 %
got a sink you can hook a hose to use warm water?
Run the block a bit get some heat in it not much
could take the rad/heater core out
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Old 01-04-2011, 02:12 PM   #131
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Re: Improve mileage 350 with Quadrajet

Quote:
Originally Posted by motornut View Post
you do use some water mixing it
unless you get the premix stuff but i prefer to topoff with the pure
keeping it in the upper 60-70 %
got a sink you can hook a hose to use warm water?
Run the block a bit get some heat in it not much
could take the rad/heater core out
no way my wife will let me use the sink in the kitchen to rinse the heater core and rad. hahahaha...no, no sink with hot water elsewhere on groundlevel in our house.
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Old 01-04-2011, 03:47 PM   #132
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Re: Improve mileage 350 with Quadrajet

haha ok
what about the drain on the tank itself?
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Old 01-04-2011, 04:13 PM   #133
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Re: Improve mileage 350 with Quadrajet

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haha ok
what about the drain on the tank itself?
I dont know what you mean?

and can I just loose the coolant though the radiator plug? or do I also need to open up the plug in the engine? (somebody told me the engine also has one? (got any pictures?)

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Old 01-04-2011, 08:25 PM   #134
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Re: Improve mileage 350 with Quadrajet

Our hot water tanks have a hose fitting at the bottom to drain it, but you can get hot water out of it too,there are two small brass screw in plugs, either side of the block up almost at the oil pan,sure take these out,but some do snap off flush ,your truck is in good shape. Might be ez removing them,may need to poke something in the hole to start a flow.
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you prob have a knock sensor in the hole on the pass side
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Old 01-04-2011, 08:28 PM   #135
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Re: Improve mileage 350 with Quadrajet

Gee didn't think hot water was bad word Lol
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Old 01-13-2011, 04:12 PM   #136
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Re: Improve mileage 350 with Quadrajet

OK, I had ordered the parts. But the lower radiatorhose has a special form and wasnt in stock. Now I have to waite for a week before this parts comes and before I can treat the cooling system.

I did install a new radiatorcap, because I was loosing coolant and one of the places was the cap.


since the thermostaat change the cooling system is leaking coolant at the thermhouse and at the radiatorcap.

I dont feel like opening up the thermostathouse again. too much of a mess in front of our door...

I guess I'll have to fill her up every now and then for a week..

this is a picture of the rad. looks bad doesnt it?




my shop didnt have Wynns in stock

Wynns Cooling System Flush


he now delivered me WOMI Koelsysteemreiniger. I guess a dutch or european product.
http://translate.google.nl/translate...D82083&act=url


I am not sure if the WOMI is what I need...since is treats chalk and sludge...

by the way? is sludge what you see in my radiator pic? is that the orange thick stuff???

Since Wynns from America I guess the best way to go would be Wynn's.

any of you guys know WOMI?
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Old 01-13-2011, 07:22 PM   #137
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Re: Improve mileage 350 with Quadrajet

You are one hard working man! However, you should repair the thermohousing before you replace the fluid. The fluid looks to me as if it has caused corrosion and deposits in your radiator and system. Be careful where you dispose of the used anti-freeze as some types are very poisonous to pets, and they like to drink it. Nothing will make you more hated by your neighbors than killing their pets. I am not sure if your truck uses an "o"ring or/and a paper gasket, but you should clean the surfaces of the housing and use good bolts and nuts to retain it. Make sure the housing has not warped from overtightening if so, make it flat again.
Sometimes electrolysis causes corrosion in radiators, but I don't know how to cure it except keeping clean anti-freeze in it. Your photographs, as usual, are great, but they do make the radiator look rather dirty inside. I'm afraid to look at mine.
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Old 01-14-2011, 03:02 AM   #138
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Re: Improve mileage 350 with Quadrajet

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You are one hard working man! However, you should repair the thermohousing before you replace the fluid. The fluid looks to me as if it has caused corrosion and deposits in your radiator and system. Be careful where you dispose of the used anti-freeze as some types are very poisonous to pets, and they like to drink it. Nothing will make you more hated by your neighbors than killing their pets. I am not sure if your truck uses an "o"ring or/and a paper gasket, but you should clean the surfaces of the housing and use good bolts and nuts to retain it. Make sure the housing has not warped from overtightening if so, make it flat again.
Sometimes electrolysis causes corrosion in radiators, but I don't know how to cure it except keeping clean anti-freeze in it. Your photographs, as usual, are great, but they do make the radiator look rather dirty inside. I'm afraid to look at mine.
thanks. the thermhouse has a paperp gasket and I replaced it when I changed the thermostat. I also cleaned the engine en house, but probably didnt tighten it well or too loose. the bolts are bad as you might have noticed.

that is why I ordered a new house and new bolts.

I also told the guy from the shop to dump the WOMI and order WYNN's flush and leak stop for me.

I'll flush the baby first and then put leak stop in the new coolant to make sure it doesnt start leaking after I flushed it. because the rust and sludge seem pretty bad.

I'll post some more pictures when I get results. probably in a week.

thanks.
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Old 01-14-2011, 03:35 AM   #139
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Re: Improve mileage 350 with Quadrajet

Hey man this is quite a thread! First I would like to point out that the vacuum valve on your thermostat housing is only open when the engine is warm and is intended to prevent the vacuum advance from being pulled in when the engine is cold. Also your vac source to that valve should be ported (no vac at idle) The EGR system is also a good thing to keep!

Another thing that helps the HEI ignition setup is a good 12 volt lead direct from the battery. Like so:

Example of bosch relay:
Amazon.com: 12 VDC Tyco Relay SPDT 20/30A... Amazon.com: 12 VDC Tyco Relay SPDT 20/30A...
Be sure to use a fuse in the lead from the battery to the relay!!!

Also this thread here on the forum has the vac diagrams for your engine:
http://67-72chevytrucks.com/vboard/s....php?p=3287463

Basically the EGR should see vac at idle with the ngine warmed up but not cold
The distributor should only see vac with the engine warm but not at idle.

There should be 2 temp valves on your engine one is for EGR and the front one is for everything else if I remember correctly.

Several of the ports on the front temp valve are common to each other while one is closed. This is when the engine is cold. The one that is closed should get the vac source (ported) from the carb.

Hope that helps not hinders! I will try to come up with a diagram but I need to know exactly what was removed from your engine and what is left to work with.
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Old 01-14-2011, 03:38 AM   #140
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Re: Improve mileage 350 with Quadrajet

Also try to use a thin gasket on that thermostat housing! Thicker ones will increase the likelihood of warping or cracking and they are easy to crack! I'd say .5mm or thereabouts.
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Old 01-14-2011, 06:17 AM   #141
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Re: Improve mileage 350 with Quadrajet

Hey SPACETRUCKIN no offense meant but this guy runs his truck on LPG or LNG, not gasoline. Therefore, EGR and manifold crossover is unnecessary or counterproductive if he is running on compressed gaseous fuel. I made the same error earlier. Kikkegek, normally "stop leak" products should be avoided as they can block off necessary cooling passages. Cleaners; yes, stop leak; no, unless you are driving a "junker" and have no long range plans to keep it.
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Old 01-14-2011, 06:33 AM   #142
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Re: Improve mileage 350 with Quadrajet

Oh no offense taken, you are correct. I was thinking about him running so much advance that it could cause knock and forgot to include that it should be switched off for the LPG. Though if you only run gasoline on the very rare occasion Kikkegek, its just as well to remove the EGR system entirely and block off the port for the valve, while you're at it remove those A.I.R. diverter tubes coming off the exhaust manifold and all their associated tubing. Seems like 3/8 (~9-10mm) brass pipe plugs seal up the holes in the manifold perfectly and it will give a much tidier engine bay.

Also the temp switch on the thermo housing comes in different temperature ranges. They are color-coded in blue, gray, black, and I think yellow or orange. You will need one that matches your thermostat or your vac advance will come in to early or not at all. Their proper name is "water thermo switch" IIRC.

+1 on "stop leak" for anything! Those products are for shady mechanics and used car salesmen!
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Old 01-14-2011, 09:49 AM   #143
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Re: Improve mileage 350 with Quadrajet

don't use the stop leak it will just clog your rad tubes up or worse places like the core
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Old 01-14-2011, 06:27 PM   #144
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Re: Improve mileage 350 with Quadrajet

he Space truckin thanks for the help.

how much difference would the direct 12V lead to the HEI make? any numbers or more info on that?
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Old 01-14-2011, 07:00 PM   #145
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Re: Improve mileage 350 with Quadrajet

No specific numbers, but I can tell you that both of the big blocks I had/have HEI on ran like a whole different truck afterwards! My 3+3 is getting about 12 mpg as opposed to about 6 before and it starts on the first crank every time now but I also did a bunch of other stuff at the same time so not sure how much of that is the HEI mod. I know it is a pretty common thing to do since HEI does some really weird stuff if it doesn't get good power. I'm kinda surprised nobody else mentioned this already.
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Old 01-15-2011, 01:24 PM   #146
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Re: Improve mileage 350 with Quadrajet

Is the vapourizer/regulator/heat exchanger functioning properly?

Every LPG system on a vehicle will have a preheater for the propane fuel. the preheater is part of the regulator/vapourizer assembly. It preheats the propane before it is injected into the engine. This helps warm a cold engine sooner and keep a warm engine from being blasted with a super cold fuel mixture. My guess is, without a properly functioning propane fuel preheater your engine is constantly being injected with a very cold fuel mixture. (just hold your hand in front of a propane bottle and open the valve slightly to see how cold).

If the engine is not warming up then the choke will be on. That rich air/fuel mixture should warm up the engine, but in the case of propane this will not be the case. Most people I know running a duel/fuel system. Use gasoline to start the engine and switch to the propane when the motor is up to operating temperature.

The vapourizer/regulator generally needs to be rebuilt every 10 years or so.

Here is a link to a catalogue page for the regulator that you probably have.

http://www.impco.ws/pdf/MASTER%20CATALOG%2010-10.pdf

Page 203.

Last edited by bctom; 01-15-2011 at 02:21 PM. Reason: Add link.
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Old 01-15-2011, 04:20 PM   #147
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Re: Improve mileage 350 with Quadrajet

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Is the vapourizer/regulator/heat exchanger functioning properly?

Every LPG system on a vehicle will have a preheater for the propane fuel. the preheater is part of the regulator/vapourizer assembly. It preheats the propane before it is injected into the engine. This helps warm a cold engine sooner and keep a warm engine from being blasted with a super cold fuel mixture. My guess is, without a properly functioning propane fuel preheater your engine is constantly being injected with a very cold fuel mixture. (just hold your hand in front of a propane bottle and open the valve slightly to see how cold).

If the engine is not warming up then the choke will be on. That rich air/fuel mixture should warm up the engine, but in the case of propane this will not be the case. Most people I know running a duel/fuel system. Use gasoline to start the engine and switch to the propane when the motor is up to operating temperature.

The vapourizer/regulator generally needs to be rebuilt every 10 years or so.

Here is a link to a catalogue page for the regulator that you probably have.

http://www.impco.ws/pdf/MASTER%20CATALOG%2010-10.pdf

Page 203.
thanks man! My IMPCO system is brand new and functioning fine. thanks!
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Old 01-29-2011, 04:08 PM   #148
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Re: Improve mileage 350 with Quadrajet

alrighty then!

Wednesday evening was the evening to do some cooling system cleaning and flushing:






First we let out all the old coolant. Man it was dirty, very brown, and lots of scale and sludge...can believe this system was filled with clean coolant last august.

then filled her up with clean water and put two cans of Wynns Cooling System Flush In her and started the engine. Let her run for about 10minutes.

I took picture from BEFORE and AFTER the flush. see if you can find the difference.

BEFORE


and AFTER


It is cleaner, but I was pretty dissapointed....

this is the result they put up on their website:



what we then did, was flush the system over and over again with clean water...for about two hours I think. Only then the water coming from the cooling system got cleaner. And in the end looked almost drinkable (NOT, hahahaha)...but it looked nice and clear.

then we filled her up with clean coolant. And I think we had the same problem everybody has when filling your system for the first time yourself. I could only put about 1,5 gallon of coolant back in...and then the system was full...hahahaha...ofcourse a lot of air in the engine...we loosened the thermostat house a little and let the air out...and then everything was fine. We filled her up again to the max and took her for a drive.


checked the coolant today and it is still clean....after 3 days of driving around...probably some 100 miles by now. So thats a good sign.

I was told this is my tempsensor. for some reason my gauge in the dash is till just saying 145-150F whiles the thermostat is 195F. So for some reason it is 40F off...

should this be my type of tempsensor?
http://d.pr/kRhN



one more question. I had bought new hoses for top and bottom of radiator. the new bottom hose had no spring in it,so I didnt use it. Now the guy from the shop checked again and he says that not all hoses nowadays have springs in them. Is this true? can I just use this hose without a spring in it?
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Old 01-29-2011, 06:25 PM   #149
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Re: Improve mileage 350 with Quadrajet

I found this short article on spark advance at this link:

http://www.rasoenterprises.com/index...-advance-curve

Dual Fuel Advance Curve
Sunday, 18 January 2009 13:20

When running a dual-fuel setup, ideally you should have both a gasoline advance curve and a propane advance curve. For older vehicles, Dual Curve makes a dual advance curve ECU for these applications under PN 40622. I contacted Dual Curve about the operation of their 40622 ECUs and they gave me the following response:


Regarding timing advance, the PN40622 is designed to give an additional 8-10 degrees of advance, after the distributor is recurved.

Please refer to the PN40622 instructions pg. 2:

“The Timing Recurve will electronically delay the factory set timing signal 15 degrees. The user must mechanically move the distributor timing ahead or advanced 15 degrees. Add 15 degrees to the original factory gasoline set point. With the 15 degree delay for gasoline, the Recurve can then provide timing advance for the higher octane LPG/CNG fuel. At idle on LPG fuel, only 10 degrees (CNG fuel, only 13 degrees) additional advance will appear on your timing device. The other degrees (5 LPG or 2 CNG) of timing are used to compute a smooth, accurate timing for RPM changes. After the (gray wire loop) fuel timing program is set-up and selected. The fuel selector switch will select the proper timing program via the yellow wire.”

You can use this ECU for straight LPG or CNG applications too. I believe the reduced timing advance when on LPG at idle would make the engine easier to start, which would be the main advantage for installing it on a straight (or dedicated) propane vehicle. However, I found that I have not had any starting problems with the advance curve used at the top of this page.


It was on this web site: http://www.rasoenterprises.com/index.php

There are also articles here on rejetting the carb, ignition and spark plug changes that are necessary in dual fuel conversions . They also state that your vacuum advance should definitely be hooked up. You might find the 195 degree thermostate too warm in the summer months. I don't have any experience running these engines at sea level, and I'm not sure how hot it gets in Holland in the summer time, so you will know better than me.
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Old 01-29-2011, 06:33 PM   #150
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Re: Improve mileage 350 with Quadrajet

Just reread your note on the hoses.

Yes, they come with out springs. Especially the bottom hose. In my experience it's the top one that takes the worst abuse when the thermostat sticks closed.

I suspect that others on this site will tell you that the factory gauges can be inaccurate. I mostly use the factory gauge to tell me if the engine is running hotter or cooler than I typically notice.
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