Thermoquad race tune

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Whats your guy's take on milling the center divider of the LD340.... I see arguments either way...

One thing that does come up frequently is mill the divider so only 3/8" remains from the bottom of the plenum and also leave 1/4" of the vertical portion on the front and back of the divider too....
 
The MoPar engines book out lines the mod.
It also crypticly states that this mod is to be used with cams over .550 lift for best results.
Considering that this mod is old, one should also look at the cams of the day with the recommended lift to be used with the plenum mod and note there duration at .050.

Consider carefully before making metal removal.
 
Oh, personally, if I had the chance to do it again, I'd start with the spacer if room allows.
 
Well time for opinions guys..... I just came across a newer Eldebrock Performer RPM Airgap intake recently....

Im currently using the untouched LD340 intake with plans on blocking the heat crossover this spring. I was also considering cutting out the base flange so the thermoquad could bold directly onto the intake without using an adaptor... OR I was looking at keeping the adaptor on the LD340 and using the additional 1" of metal to create a long tapered transition from the carb into the intake and keep more heat away from the carb. Currently the entire spread-to-square transition takes place within the 1" spacer.

Should i go that route or should I try this new Air gap intake with the adaptor and TQ?

Im all ears.........
 
Have you guys had issues with fuel evaporating thru the bowl vent lines? When i rebuilt the carb last year i check to make sure fuel couldnt leak from the lower wells so i am ruling that out right now....

Seems that after about of week of sitting the bowls are dry since i can hear them fill with fuel when i turn the pump on......

Any thoughts?
 
71duster06 said:
Have you guys had issues with fuel evaporating thru the bowl vent lines? When i rebuilt the carb last year i check to make sure fuel couldnt leak from the lower wells so i am ruling that out right now....

Seems that after about of week of sitting the bowls are dry since i can hear them fill with fuel when i turn the pump on......

Any thoughts?
Click to expand...

A big YUP! I had to install an electric fuel pump to aid in getting the gas up quicker.

Just out of curiosity Kyle, I took a cap from a spray bomb and put about an inch of gas in it one hot humid afternoon and set it on the bench. 24 hours later the cap was bone dry, it had all evaporated in a 24 hour period. The gas we have today is lousy.
 
MoPar used a very thick gasket to help keep there carbs cool. It is not to easy to find that gasket by it self. AdamR did post a place that sells them. I lost the link though.
 
Bad Sport said:
A big YUP! I had to install an electric fuel pump to aid in getting the gas up quicker.

Just out of curiosity Kyle, I took a cap from a spray bomb and put about an inch of gas in it one hot humid afternoon and set it on the bench. 24 hours later the cap was bone dry, it had all evaporated in a 24 hour period. The gas we have today is lousy.
Click to expand...

I remember you saying that last year and actually got me thinking about this too....

Is there any improvement/change when capping these vents?
 
LOL, OK then. When I made the thick gasket mention, it was to add in an item that helps control heat to the carb which will produce multiple positive things.

Will it solve the mysterious disappearing gas issue? More likely not by itself. But! If MoPar used a thick gasket, there's good reason for it. If the carb see's less heat, then there's less heat after shut down. Keeping the fuel cooler will help it stick around.

I noticed earlier you mention capping the vents. Inside the air cleaner it is not a good idea. They are there to provide a vent to the bowl. Gas will escape from there but it should not at a rate of a dry bowl the next day.

There is also the tube on the drivers side that may not be sealing. That may be capped.

The only place I can think of fuel escaping is a cracked bowl or jet well downwards into the engine.
Floats adjusted well/right?

After this, I'm stumped.
 
rumblefish360 said:
LOL, OK then. When I made the thick gasket mention, it was to add in an item that helps control heat to the carb which will produce multiple positive things.

Will it solve the mysterious disappearing gas issue? More likely not by itself. But! If MoPar used a thick gasket, there's good reason for it. If the carb see's less heat, then there's less heat after shut down. Keeping the fuel cooler will help it stick around.

I noticed earlier you mention capping the vents. Inside the air cleaner it is not a good idea. They are there to provide a vent to the bowl. Gas will escape from there but it should not at a rate of a dry bowl the next day.

There is also the tube on the drivers side that may not be sealing. That may be capped.

The only place I can think of fuel escaping is a cracked bowl or jet well downwards into the engine.
Floats adjusted well/right?

After this, I'm stumped.
Click to expand...

Good call on the gasket... ill pick on up and try it soon. ill check the drivers side tube too.
 
Chek out Beweys post "Thermoquad mods that work" in search, posted a few weeks a ago,
lots of great performance mods
 
Brooks James said:
Chek out Beweys post "Thermoquad mods that work" in search, posted a few weeks a ago,
lots of great performance mods
Click to expand...
WHOA! 10 YO thread back from the dead.

I see your doing a deep dive there Brook! Nice find.
 
rumblefish360 said:
WHOA! 10 YO thread back from the dead.

I see your doing a deep dive there Brook! Nice find.
Click to expand...
A few months ago I tried to revive interest in the TQ. Ive not had a better street carb than the TQ, I had a Qjet in the 70s that also ran damn good. Ive been trying for years to learn the hot tuning methods for a TQ. Bewy came through, I am so grateful. I have heard that a good tune modify can bring 20 extra hp over a stocker.
I anticipated the demise of the TQ, understandably so, as metering rods, large jets are either non existent or expensive, and to get the last drop of hp , dyno tuning is best.
 
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