Carburetor Dyno Comparison: Edelbrock VRS 4150 vs Race Demon

Рет қаралды 5,255

Күн бұрын

Пікірлер: 21

@ddogmog 3 ай бұрын

Thanks for the great post - The first one I've seen w/actual runtime and real time data. Thanks for sharing your findings and opinion.

@MarksMuscleCarGarage 3 ай бұрын

Thanks, glad it was helpful.

@longhairscorpio3976 4 ай бұрын

annular discharge is an advantage especially on the top end have had three (hollley 4010/4011/560 race 2bbl)annular carbs and both top end and cold weather performance was great the 4 bbls didnt like getting warm in the case of that model type the 2 bbl had no issues

@willbar1961 4 ай бұрын

That Edelbrock is slick. I've been out of it so long I haven't ever seen it. Still have only smaller street carbs. 600 and 650 Holly and a 600 Edelbrock but they're for lower power small block V8s. The Edelbrock is much better than the Hollys for me.

@MarksMuscleCarGarage 4 ай бұрын

Yes, the Edelbrock Performer series carbs are very reliable and perform well for street driving. I've run one on my 69 Mustang for years and never had any problems with it.

@willbar1961 4 ай бұрын

@@MarksMuscleCarGarage Yeah I have the Edelbrock 1406 on a Jeep with a 304 V8, small cam and fenderwell headers. Not high horsepower but good low/mid torque.

@vrm86gt 4 ай бұрын

nice job!

@MarksMuscleCarGarage 4 ай бұрын

Thanks!

@approachingtarget.4503 4 ай бұрын

Annual boosters mix fuel better and allow more flow.

@oscaracme 3 ай бұрын

Annular boosters do mix fuel better early, but do not flow more air.

@TheDynotuner 3 ай бұрын

Those Demon's came with some other air bleeds as they had some issues. But having to run more than a 10 jet sized spread means the air bleed sizing is off... How did you convert it from alcohol to gas? Im gonna guess you changed to metering blocks. And curious what that mechanical pump is feeding them at 5000+ for psi?

@MarksMuscleCarGarage 3 ай бұрын

The 750 Demon I have has a stock jet size of 75/83 with power valve in front none in rear. I ran it on the street on another motor with 74/83 jets and AFR were pretty well calibrated. We went down 3 in the front and 3 up in the back on the dyno to arrive at the 71/86. This was what my machinist recommended to lean it out on the dyno, which seemed to work. We also made an air bleed change on the high speeds as well. If I ran a power valve in the rear the spread would not have been as large. The Edelbrock VRS 4150 has jet sizes of 72/72 out of the box but it has power valves both front and rear hence the square jetting. We used the same down 3 in front up 3 in the back to lean the VRS 4150 out, ending up at 69/75 .The Edelbrock and Demon use the same air bleeds oddly enough which differ from Holly air bleeds which are fatter on the top though the thread size is the same as the Demon and VRS 4150. For the alcohol to gas conversion, I changed metering blocks, squirters and needle + seats, all according to specs in the Demon carb book I mention in the Demon carb video I made on the subject. I'm not sure about the pressure on the carb during the dyno runs - we didn't have it instrumented. The gage on the carb fuel line showed about 6-7 psi when we were tuning it. The pump is a Carter "Super Strip" pump that flows 120 gph at 6-8 psi which is enough for 1000hp according to Summit's online fuel pump flow/hp calculator. The stock SBF pump only flows 40 psi and is good for 450 hp.

@ScottMartin-h1s 14 күн бұрын

BS.. we saw the demon hit 500, twice..

@MarksMuscleCarGarage 14 күн бұрын

The torque and hp numbers jump briefly at the end of the pull when he releases the theottle. I believe that is the dyno frewheeling as a result and are not real numbers

@markgoulette5056 3 ай бұрын

Additionally, there is no "ideal AFR" for an engine. An engine wants what it wants, period. One engine combo might make best power at 13:1 afr, another might want a 12.5:1 afr. It's all about the combo and what the engine wants. NEVER tune an engine to a specific afr, read the plugs, and give it what it wants. In this video, it shows the demon carb was either not well tuned or simply mismatched for the combo. The Edelbrock was a better match for the combo....

@MarksMuscleCarGarage 3 ай бұрын

@@markgoulette5056 Could be. Could also be we tune the Demon to perfection and doesn't outperform the other carb. +1 on reading the plugs. We read plugs on multiple runs.

@cedricwilson2055 2 ай бұрын

On a dyno, max power and plug reading don’t go hand in hand? I f I’m making max power what does it matter what the plugs read ?

@MarksMuscleCarGarage 2 ай бұрын

@@cedricwilson2055 Well if you're making max power your plugs will be clean, white looking for the most part with some tan further down on the insulator. If you were running rich you wouldn't be making max power and your plugs would be showing some blaok or gray on the insulator and electrodes. Also if the engine is running into detonation problems you should be able to see that on the spark plugs as well.