Thermoquad on Edelbrock RPM Airgap

[71duster06]

I just copied and pasted this from another thread i had going but didnt get any responses.

Well time for opinions guys..... I just came across a newer Edelbrock 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 of the adaptor 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.........
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[roccodart440]

The Eddy Perf RPM intake is probably the best dual plane out there. I'd definitly run it. A 1" HVH supersucker or wilson spacer will get you about 10hp and 10-15 ft. lbs.

The carb would be the next thing to upgrade. Putting a thermoquad on that intake is like... well you guys filll in that analogy

 

[K.O. SWINGER]

The Eddy Perf RPM intake is probably the best dual plane out there. I'd definitly run it. A 1" HVH supersucker or wilson spacer will get you about 10hp and 10-15 ft. lbs.

The carb would be the next thing to upgrade. Putting a thermoquad on that intake is like... well you guys filll in that analogy

I disagreeIfeel the rpm has a small over all advantage but will even get smaller with your planed mods for the L D .as far as the thermoquad you will be hard press to find a better all around performance cab if set up correctly and if you are versed in T Q mods it can be a monster!! with best mpg as a added plus

 

[71duster06]

I disagreeIfeel the rpm has a small over all advantage but will even get smaller with your planed mods for the L D .as far as the thermoquad you will be hard press to find a better all around performance cab if set up correctly and if you are versed in T Q mods it can be a monster!! with best mpg as a added plus

Agreed. I am sticking with the thermoquad as my carb. Im my other thread youll see that I did a 1/4 mile comparison between a new Holley 750 and the TQ. I picked up over 3/10 of a second but more importantly i gained 5 mph with the TQ at the traps (mid 13s). The issue im tweaking with right now on the TQ is the 60 ft time which was much worse than the Holley's.... once i get that adjusted im in the high 12s with 3.23s.

So with that... now its deciding which intake to go with.....

 

[71Scamper]

The Eddy Perf RPM intake is probably the best dual plane out there. I'd definitly run it. A 1" HVH supersucker or wilson spacer will get you about 10hp and 10-15 ft. lbs.

The carb would be the next thing to upgrade. Putting a thermoquad on that intake is like... well you guys filll in that analogy

....is like tits on a bull! :glasses7:

 

[K.O. SWINGER]

I would say to increase primary jet size, bore shooters and steeper rear gears would provide much stronger launch ...with rpm air gap a having small advantage

 

[71duster06]

I would say to increase primary jet size, bore shooters and steeper rear gears would provide much stronger launch ...with rpm air gap a having small advantage

I have the primary jets for a 440 carb. Right now it's just some tuning that I have to do.

I'm sticking with the gears I have since I do primarily highway travel. Im totally fine with sacrificing a bit of launch. Sounds like its not really worth me switching intakes tho....

 

[rumblefish360]

The LD-340 modded as per the MP books is an excellent t mod except the center divider wall should be left alone. Milling the divider is for a leagal cheats d works with high lift cams with a good bit of duration.

The TQ mod to the LD-340 is excellent by itself. For certain, space the carb up.

Now the RPM-AG is a better intake by a few scant ponies. The carb of choice should be a Holley and not a run of the mill cheapo Holley. Spend some dough on a nice serious unit and tune the heck out of it. It'll take the edge over the older units, but, not by much.

 

[71duster06]

The LD-340 modded as per the MP books is an excellent t mod except the center divider wall should be left alone. Milling the divider is for a leagal cheats d works with high lift cams with a good bit of duration.

The TQ mod to the LD-340 is excellent by itself. For certain, space the carb up.

Now the RPM-AG is a better intake by a few scant ponies. The carb of choice should be a Holley and not a run of the mill cheapo Holley. Spend some dough on a nice serious unit and tune the heck out of it. It'll take the edge over the older units, but, not by much.

Well I think I'm going to stick with the LD340 and mod it to fit the tq so I won't need an adaptor. I will try one of these tho just to see the difference at the track. http://m.summitracing.com/parts/mrg-3406/media.

 

[rumblefish360]

IF I am correct, that will NOT fit a TQ. It is for a Rochester.
MoPar used to sell 1/4 inch tuning spacers. The aluminum open units sold for typical adaption could be hogged out for use.

IF anything, try and find the OE "Thick" gasket to use. This would be best to keep the TQ cool and raise it some. (1/4 inch)

 

[71duster06]

IF I am correct, that will NOT fit a TQ. It is for a Rochester.
MoPar used to sell 1/4 inch tuning spacers. The aluminum open units sold for typical adaption could be hogged out for use.

IF anything, try and find the OE "Thick" gasket to use. This would be best to keep the TQ cool and raise it some. (1/4 inch)

Ok. I did find a couple spread bore spacers, not adaptors.

Another random question... any difference between an open spacer or a 4 hole spacer?

 

[71duster06]

IF I am correct, that will NOT fit a TQ. It is for a Rochester.
MoPar used to sell 1/4 inch tuning spacers. The aluminum open units sold for typical adaption could be hogged out for use.

IF anything, try and find the OE "Thick" gasket to use. This would be best to keep the TQ cool and raise it some. (1/4 inch)

Also, Mopar Muscle had an article that used a performer RPM (non Airgap).... if the car is summer driver only, street/strip, then they highly recommend blocking off the heat crossover ports. this would help keep some direct heat away from the carb.... Typically doesnt get out of the garage under 60 degrees

 

[roccodart440]

I disagreeIfeel the rpm has a small over all advantage but will even get smaller with your planed mods for the L D .as far as the thermoquad you will be hard press to find a better all around performance cab if set up correctly and if you are versed in T Q mods it can be a monster!! with best mpg as a added plus

A small advantage is an advatage, not to mention the air gap function and the looks of it.

Agreed. I am sticking with the thermoquad as my carb. Im my other thread youll see that I did a 1/4 mile comparison between a new Holley 750 and the TQ. I picked up over 3/10 of a second but more importantly i gained 5 mph with the TQ at the traps (mid 13s). The issue im tweaking with right now on the TQ is the 60 ft time which was much worse than the Holley's.... once i get that adjusted im in the high 12s with 3.23s.

So with that... now its deciding which intake to go with.....

3/10ths is HUGE! I learned this early on with my first dodge dart when I switched to a holley, easy to tune, easy to get parts and without a doubt offers more performance as you have proven for yourself.

....is like tits on a bull! :glasses7:

Also, Mopar Muscle had an article that used a performer RPM (non Airgap).... if the car is summer driver only, street/strip, then they highly recommend blocking off the heat crossover ports. this would help keep some direct heat away from the carb.... Typically doesnt get out of the garage under 60 degrees

This is what I was talking about. Also the blockoff is a no brainer for a performance oriented car. It's fine to far below 60 degrees.

 

[rumblefish360]

Ok. I did find a couple spread bore spacers, not adaptors.

Another random question... any difference between an open spacer or a 4 hole spacer?

In general a 4 hole spacer adds torque a d a open spacer adds HP.
I do not think you will find a 4 hole TQ spacer or adapter.

Also, Mopar Muscle had an article that used a performer RPM (non Airgap).... if the car is summer driver only, street/strip, then they highly recommend blocking off the heat crossover ports. this would help keep some direct heat away from the carb.... Typically doesnt get out of the garage under 60 degrees

Yep

 

[roccodart440]

The HVH 4 hole made 10 more hp and 12 more ft lbs on back to back pulls on my 440 at the same RPM. I've seen simliar results on my engine builders dyno with other engines, not just MOpars.

 

[71duster06]

A small advantage is an advatage, not to mention the air gap function and the looks of it.



3/10ths is HUGE! I learned this early on with my first dodge dart when I switched to a holley, easy to tune, easy to get parts and without a doubt offers more performance as you have proven for yourself.





This is what I was talking about. Also the blockoff is a no brainer for a performance oriented car. It's fine to far below 60 degrees.

Actually the TQ was the faster of the two. Not going back to the Holley.

 

[DaveBonds]

Are you planning on running it chokeless or manual choke? I have a TQ with no choke on one of the cars here and it is very tricky engine to start cold.

 

[DionR]

Are you planning on running it chokeless or manual choke? I have a TQ with no choke on one of the cars here and it is very tricky engine to start cold.

I fought that also on my Magnum headed 360 with the dual plane M1. Ended up building a mount for a choke off an aftermarket TQ. Seems to work good, haven't have to pop the hood to get it started since I got it working. Not going to pretend it is perfect, but it was kind of fun and got the job done.

 

[rumblefish360]

Nice bracket job! I had done something similar in the past and hooked up a Edelbrocj electric choke for my TQ.

 

[roccodart440]

Actually the TQ was the faster of the two. Not going back to the Holley.

I went back and caught that. I can't begin to understand this but hey, use what works for you.

 

[rumblefish360]

The spreadbore tends to make more torque at lower RPM's and provide more top end power per build, not every build responds the same way. Steve Dulich has had a few write ups where he had his TQ out perform the dyno shops Holley.
IMO, a well tuned TQ is a great street strip carb worth looking into.
Remember this carb, the TQ was born and designed to be a race carb before it was redone to be a daily operator for cars.

 

[DionR]

Nice bracket job! I had done something similar in the past and hooked up a Edelbrocj electric choke for my TQ.

Any pictures of that? Really like to see how you made that work.

I looked at doing something difference since my setup uses some parts made of unobtanium. Still looking for a better cover, probably go EFI before I find it. A more mass produced aftermarket kit for a difference carb would make a much better setup.

 

[K.O. SWINGER]

The spreadbore tends to make more torque at lower RPM's and provide more top end power per build, not every build responds the same way. Steve Dulich has had a few write ups where he had his TQ out perform the dyno shops Holley.
IMO, a well tuned TQ is a great street strip carb worth looking into.
Remember this carb, the TQ was born and designed to be a race carb before it was redone to be a daily operator for cars.

thanks RUMBLE...I couldn't have said it better my self

 

[rumblefish360]

thanks RUMBLE...I couldn't have said it better my self

Thank you! Most everyone forgets this and super short sells the carb.

Any pictures of that? Really like to see how you made that work.

I looked at doing something difference since my setup uses some parts made of unobtanium. Still looking for a better cover, probably go EFI before I find it. A more mass produced aftermarket kit for a difference carb would make a much better setup.

Ahhhh, I don't think so on the pictures. Basicly what I did was take a flare plate and cut the TQ shape out and drilled it to fit the intake. Put the carb on top to clearance it. Then I took the electric choke a d made "L" brackets to hold it up straight. Used a metal coat hanger for the connecting rod.

It's something you have to fiddle with a while to get it to work just so. It was t to pretty looking when ingot down with it. It was just an"Rough drafts" to see if I could do it. I never got to a finished state/version of it. I could probably duplicate one in 2 hours from scratch to working unit. Though it would still be a butt ugly version.

Finish work could take some time though since you would want a good looking piece because it is an interesting part to begin with. Making things look good cam take awhile.

 

[DionR]

Hmmm...might have to look into that again. I didn't think it spun the right way to close the choke but I see now I missed something. Sure be nice to be able to buy a new cover, the setup I have needs a better one and it doesn't seem that they made a replacement for them.