Considering using the Quick Fuel Brawler 670 when I do the top end performance upgrade on my 403. The quadrajet on it now has a solenoid that governs the engine idle when the AC compressor kicks on. I am wondering how will this be done if using the Brawler. Is there a solenoid and bracket that can be used on it the same as with the QJet? I have seen them for some Holley's but from what I understand that design actually requires a "tap of the accelerator" when the AC comes on in order to function. That isn't required with my current QJet. Anyone here have experience with this?

 

Here you go.

 

Yea I had seen that and was sorta hoping it wasn’t the only thing out there. Sorta weak and sorta expensive imo. I mean if one works on a a QJet without pattin the foot-feed what’s the weak link in this one. Or does it do the job ok, I guess would be my question

 

Look and see if you can adapt the stock one before looking to alternatives. Or you can try running without it and bump the idle up in the warmer months.

 

Will do @oldcutlass thanks. Will also search for a bracket and possibly use this less expensive solenoid

https://quadrajetparts.com/idle-sole...er-p-2131.html

 

As said, you should be able to adapt that bracket or make a new one to bolt to the intake. Also consider sending your 403 Qjet to Everyday Performance for a recalibration. Those are the best Qjet's, 800 cfm and have many improvements over the early Qjet carbs. But the idle especially is calibrated extremely lean. You can add a threaded removable plug and slot the APT or get Ken at Everyday Performance to do it, APT stands for adjustable part throttle fuel mixture. I cut off a 1/4" bolt, cut a straight slot in the top, tapped the APT access hole then cut a straight slot in the APT itself. You can go from a tire burning mixture to a lean as you dare mixture for fuel economy. I gained 3 mpg by doing that. With a core it will be cheaper for sure over the Quickfuel carb, even if your carb needs bushing work, which it probably will. I skipped the extra cost of plating as my carb was clean like yours. Good luck.

 

I had actually emailed Ken about doing a rebuild of my QJet before deciding to take on the top end upgrade. But one of the reasons I decided to go with the top end work was to hopefully get some better gas mileage, especially when towing, out of a different style carburetor that's easier to tune. One can watch the gas hand move when opening up those huge secondaries of the QJet which is quite often when pulling a 4000 lb Airstream. I currently get around 9 mpg around town and 5 mpg when towing. The 3 mpg gain you were able to squeeze out of it is certainly an appreciable amount, I'd love to get 9-10 towing. I've not seen any data on the mpg of the Quickfuel and am only assuming it will be be better. Anybody have thoughts on that?

 

My thought is if your new carb has smaller secondaries, your engine will have less power.

If you really want better gas mileage, why not go with a 2bbl carb?

 

Also, make sure it IS an AC idle solenoid and not an anti-dieseling solenoid that's on all the time. If it's the latter, you can ditch it and increase idle via the carb.

 

Have this on my son's 70 Cutlass Supreme - it works great:

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Have a toggle under the dash. Flip the toggle and it pushes that gold piece on the end forward. You can screw or unscrew to make it as long or short as you want. It took some trial and error but it raises the idle by about 300 RPM. I actually use it during warm up too. For the AC I flip the switch, press the gas pedal and the RPMs go up 300, run the AC and the car idles at the same RPM as it does with the AC/toggle off (about 800 RPM). When I turn the AC off just flip the switch and it drops back to where it was. I used it on my 442 also before I upgraded to Go EFI 8. This one is on an Edelbrock carb. You may have to mod a custom bracket but should be able to use it on any carb. I don't think tapping the gas pedal is a big deal but you do have to do it with this one. The only negative is if you're sitting at a light in drive and want to turn it on you have to put it in neutral or park. I understand it's better NOT to have to do that (like with my GO EFI 8 on the 442), but don't think it's that big of a hassle.

-Joe

 

That is a tough one, it will be in the secondaries a lot. Another carb to consider is the 750 Street Demon. A bit smaller secondaries, but still has triple stack boosters on the primary side. They enlarged the 625 to 750 by enlarging the primary bores. What are you currently running for timing? Ethanol gas? All these things make a difference.

 

Embarrassed to say, I don't know what the local garage that did the tune up on the engine after I bought the car about 4,000 miles ago set timing at. I do use ethanol, currently 93 octane, would love to be able to drop to regular or mid .