Holley carburetor tuning guide ( 4150 Carbs ) Part 2 

This is the first guy that actually speaks any sense about holley carbs everything you say I agree with. I have a fully built 351 Cleveland and It got to the point with my Holley that the factory metering block was crap and was not giving the engine enough fuel when the power valve was open it would just lean out no matter what I did. I went and bought a QFT metering block that has the adjustable power valve channel restrictions and upped the jet engine has never run better after that. I’m event thinking of buying a QFT brawler carb.

I just found this old video of yours. Thanks man this is by far the best video on tuning in a carb

Hands on best tuning video i've seen yet. Fine work.

Very informative Mate. Thanks, this will definitely help me tune my Cleveland. All the best from Australia 🇦🇺.

Be thankful that she allows you the small corner, bro'! :P

Either you have a cam with ridiculous duration and your engine needs to idle at 1200+ RPM to keep running, or you hooked your vacuum gauge up to a timing port if you're only seeing 5" at idle. The number of the power valve is the inches of vacuum at which it opens. If you really had 5" at idle and swapped in an 8.5 PV, it would always be open, adding to your mains. Since you say the default 6.5 wasn't enough, that means you have at least 15" at idle which is in the "good" range for a street motor. Just so everybody knows, that port on the primary metering block is a timing port for vacuum advance and shows a very weak signal at idle. Manifold vacuum ports are always on the throttle plate, and that's where you should connect your gauge. That being said, great videos. You're doing a great service to enthusiasts.

Your vids is excellent, very well made! I feel sad when I see that they got viewed rarely and rated. Subbed to you back then when you commented to roadkill co-host video. Just excellent

Cool vid. I've argued with tons of people about power valve tuning and the stupid holley method. I usually explain it like an adjustable lean cruise afr to full power afr switch. Also been known as an economizer valve cause it leans the mix when closed.

Thanks man, I just finish building a 505ci. I live in Co so as you know its starving for air. Had a 770 Holley Avenger, but these stroker motors like at least 1150-1200. I borrowed my buddy's 1000 4150 and just got it on and will be doing some tuning. Thanks to you, you made it very simple. In the past, I've paid people bc I was scared of the tune! Not anymore;)

nice video bro! goodjob at the end showing your tach and adjustments made. appreciate the video. helpes me tune my 850dp. on my 402ci big block chevy.

Sweet I've just got my wideband in ! Your the first to suggest no PV's which may suggest why I'm running rich, I went down 2 jets but still foils the plugs slightly !! I have a primary PV but I'm gonna try blocking that too cheers for the great tip and I'll also pay better attention to my wideband rather than vacuum :)

Bad ass Tyler ! Thanks for the tips....Coors Light RULES!!!!

Thanks for the 4150 videos Tyler. It helped me get my bbc idling correctly this weekend with some new Proform bowls. Probably didn't need them, but the sight glass really helped. Your video goes in depth, yet explains a lot of basic carb concepts and links them all together. Great job!!

Very in depth videos. Two thumbs up

That was really great. Great video and a ton of help!

Good job. I like learning from your gauge and seeing what works for you. Currently installing an AEM wideband and E85 metering block kit in mine.

Seems crazy that your PV would be so far off the Holley Chart...the number is supposed to be set based on the vacuum, I would think maybe your vacuum reading was wrong.

Thanks for the video! I believe I learned something

Again, Thank You! Wish you were my neighbor lol

time 5:55: wouldn't worse hesitation w/ 2.5 PV indicate not enough pump shot? starvation before redline at WOT would indicate PV opening too late (PV number too small), correct? momentary hesitation is pump shot (volume and or timing). higher speed starvation is PV opening too late (PV number too low), starvation at WOT redline is jets too small / PV not flowing enough. starvation above a certain RPM regardless of tune is carb too small.

Hey thanks for adding your setups and results! Mine is about identical to the first setup on the video right now, but I have a summit 750dp and there is no info on it

4 corner idle = 3/4 turn on each corner and that's a start ……… you turned in a lil over 3/4 …. than turned them out like a 2 corner idle 3 flats 1.5 turns ….. might confuse some

Nice info on both vids! Thank You! Much better than Holley's. Wish you were here to fine tune the MasterCraft Ski Boat

Nice helpful vid, but really man; Coor's lite has nothing to do with beer!! :D LOL

My dad has tried everything, he has a mild bbc 750 vac 2nd, 70 squirts 6.5 pv, and 12.5 to 13.0 vac reading but seems to idle rich, strong fumes and visible out the pipes and plugs are black

This weekend I drove my car up to T-Mobile store, when I was ready to leave, the RPMs on my car has gone from 600/700 up to about 1600/1800. So I drove her home, the RPMs will not drop below 2500. Got into the garage, looked over everything didn't see any leaks around the carburetor I did notice that my throttle cable to my transmission had broken off at the carburetor. You think this could have been a problem? I get driving it could be, but at idle it still wouldn't come down to guards if I adjust the idle screw or not. Thank you in advance

When you turned the carb upside down without the squirter installed, you never mentioned the needle underneath the squirter that fell out! 8:39

Nice info and great angles !! how come you can't make a longer video and go more in depth that's what your all about :) Cons. you said in Part 2 you will explain why you don't believe in using a vacuum gauge to dial in idle or power valves...be good if you elaborated on getting close to exact idle mixes correct & how/why. *Maybe a vid on proper tuning and common issues & fixes (eg lean/rich idles or bad mileage issues) doesn't a power valve rely on correct idle & vacuum to open although I didn't see you talk about this maybe I missed it or maybe because you chose the 8.5 which throws Holleys method out the window (but you didn't confirm if this was why) Keep up the great work

When you watch air fuel ratios, what are you using to monitor? Do you have a dual sensor setup per bank?

Holley 4150...idles good..no leaks...put car in gear i got flopped around like im stabbing the fuel and letting off getting jerkered around...any ideas..this carb did work and for no reason its all messed up..car is runable..not deivable

Great job with the carburetor. thanks

I probably missed it in the video but why do you prefer not to tune with a vacuum gauge.

good videos, interesting results going to the 8.5 p/v goes against everything I've known but I am going to try the same with a 351C that is giving me headaches How do you have your A/F ratio gauge hooked up. Thanks

Man corner? Ha i have a whole garage! She doesn't even dare try taking that over.

Sounds to me like you got the motor running real sweat 👍

Great job very informative

Would this be similar for all Holley carbs? I have a Truck Avenger 670 carb that needs some adjustment

whats the trans and rear gear? 7 grand in my truck in 2nd with a th400 and 2:08's is 162 MPH!

i just liked the Music theme on this video, that's All.. 👍

5.5" of vacuum is a lot lower than I was expecting. What are your cam specs if you dont mind me asking?

Is Coors a sponsor? If not you need to hit them up, lol What should your A/F be at WOT? Thanks for the great video's

How long does it take to dial in this

Well it sounds Nice.

What motor is in this vehicle? It pulls nice and sounds great! 👍👍

Nice vids. Subbed.

that truck hauls a$$

My Barry grant 750 has 4 corner idle mixture but no power valve in the rear. I get a bad hesitation going from primary to secondary. And I don’t have a a/f gauge I do it all on plugs. Plugs look a little fat on the gas ring (100 octane av gas) but it seems to lose power on the top end. It’s a 302 and I think it’s just not getting enough vacuum signal because the carb is too big. What are your thoughts on power valve block off. Will be primarily a track only setup.

Isn’t your power valve opening at idle once you up it to 8.5?

great info!

To hear my wife let me just breaks my heart no man should have to say those words be single my friends

2 words that should never go together-light and beer = yellow water. Carb stands are cheap. Otherwise youre working with the unit being supported by the linkage and pumps .

Nice info! What do you think about using a block off for the power valve on a street car?

What about transfer port sync...no mention at all??

P.s i have never rebuilt a carb..i have 5 that leak gas from all over

Is that an S10?

2 way relationship.

coors better be sending you cases of beer..

Where did you place your O2 bung?

Thanks for the info but your beer choice Coors Lite is like making love in a canoe , fning near water .

On your truck)

Dump the background music

you not orgenized well loll, strip the carby on a tool box, ??????

n.m...lol

Your video popped my tire... thanks for nothing

Daamn dude you might wanna quit smoking...your air exchange sounds horrible...