HEI Ignition Tips for Your Engine

Nothing proves engine theories or new parts like a little dyno time. Horsepower Monster decided to take a closer look at ignitions in general and the ever popular HEI ignition in particular. We also tested a stock unit against a high-performance unit from Performance Distributors, and the dyno proved that all HEI ignitions are not created equal.
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[@hmayerv8]

All well and fine for high performance engines. Seriously the stock points system and thereafter the stock GM HEI is the perfect distributor for stock engines. They've run these on millions of American made cars from 70s onwards. Time tested perfection.

[@ViewThis.]

On my supercharged engine I first used a regular distributor and separate coil. I later changed to HEI 50,000 volt and it made a huge difference, especially in the strength of the idle while in gear with my foot on the brake.

[@Dannysoutherner]

For the average street motor an off the shelf HEI is perfect. They are dirt reliable unlike the Ford Durafail system. If you have the misfortune of losing an ignition module they can be gotten pretty much anywhere. Walmart used to carry them. I have made the mistake of using esoteric fancy gear and having it die on me leaving me on the end of a hook. Edelbrock carb and HEI is a bulletproof combination for daily use.

[@garylemay9275]

Where do the wipers attached to the distrutor go to

[@michaelstarr5861]

Since I started driving with a vacuum guage on my dash, it's gone from from 10mpg to 14mpg! Simply installed a brass T adapter and ran a hose though the firewall. Then just keep vacuum in the optimum zone while accelerating.

[@MiguelSanchez-st3pv]

Just got a dui dizzy for my ski boat excited now 😁

[@TubeKontrast]

hi, what is the way when the removal position is lost? the zero mark on the flywheel is finger on the cylinder 1 cable? I have made the fine marking before, but which gear position clicks is lost, is a Nissan H25 engine Forklift,

[@jayhagsrc3322]

I'm pretty sure the vacuum advance advances timing because at part throttle the air and fuel in the cylinders isn't as dense as wide open throttle, therefore it takes longer for the mixture to burn. Vacuum advance isn't going to make a difference doing wide open dyno pulls. Vacuum advance is done for driveability. If you have too much vacuum advance the motor will "ping".

[@AustinHarmon1994]

On my 350 vortec i set my timing at 10 and total was 34 and dint use vacuum advance for that reason. Didnt want any pinging.

[@DANTHETUBEMAN]

@@AustinHarmon1994 how is your gas mileage? It would be great to see if you can improve mileage and keep performance.

[@earlbrown]

It's nice to see someone that ACTUALLY knows how vacuum advance controls the curve under real world use. At WOT vacuum advance doesn't nothing. I could tell they weren't fully up to speed when they hooked up the advance. They ran the hose to a ported vacuum source, then had to move the distributor. The whole point of a ported vac is it does nothing at idle. So if they had to move the distributor, they throttle blade was open too far on the carb. Which doesn't explain why the HP didn't move much. If they had to back off on the base timing setting to maintain base timing, they should have been lacking full advance up top. ....so this video isn't really a tech video, it's an ad for D.U.I ignition systems.

[@FastBowtie388]

I'm confused. What does a vacuum secondary carb have to do with the vacuum advance? Mechanical secondaries still has a ported vacuum connection for the distributor.

[@DANTHETUBEMAN]

Great video own dat zapper, and big gap plugs. I been doin this way 4 yearz

[@bobstephens8851]

I use vacuum advance on full manifold vacuum to help my engine idle better with a big cam, also keeps plugs cleaner.

[@aboutmyfathersbusiness8324]

Agreed; It also drops my idle temps 20 degrees.

[@cjbert6790]

On some engines it really helps. The reason being that it can increase the vacuum signal to the carburetor.

[@roadrunner0079]

Question if the gear bottom of the distributor fit sworn what did affect the advanced vacuum on the distributor

[@rockinbass01]

you guys should make a video explaining how to tune the vacuum advance like how much to safely ad and how to tune when it drops out

[@Gettinbentoffroad]

It helps mainly at low rpm when the car runs lean at idle the higher vacuum also at low rpm advances your timing to burn the fuel better when you open up the advance does nothing.

[@hotrodray6802]

I dont believe that they actually know how, based on this video.

[@jamyers1971]

@@Gettinbentoffroad not low rpm, but at low LOAD. Vacuum advance simply adds timing at low load, regardless of rpm

[@earlbrown]

@@hotrodray6802 They don't. When they had to adjust the distributor after hooked up to a ported vacuum source,they should have known the throttle blade was open too far. What's 'odd' is they had to back off on the distributor timing, didn't change the stops on the mechanical advance, yet the engine made the same power up top... With a backed off distributor. Not to mention, ported vacuum is a sloppy way to lower emissions at idle by intentionally making a car run poorly by filling the exhaust with unburned A/F. That kind of ''tuning'' has no place on a dyno or when dealing with professionals setting up a vac advance distributor. Manifold advance if what you want when you're tuning a car for part throttle real world use and gas mileage. (and the weights, springs, and stops set accordingly). A lot of 'experts' think manifold signal causes pinging and detonation due to the signal source. When they don't realize you can't use ported stops and base settings with a manifold signal. Same as you wouldn't use a distributor set up for full manifold vac and send it to a ported vacuum port. There's a whole lot of 'turners' out there that don't know how to tune. This wasn't tech, it was an ad for D.U.I ignition systems. That's why they had to close the gap with the stock unit. So the dyno curve would show a loss of power. A good HEI will light off only 400hp all day long if it has full voltage running to it.

[@AZpatriot69.]

What is the part # of the cam?

[@markrussell1100]

I would have liked to have seen where you connected the wires.

[@braddenning1617]

I built a GMC 292 inline 6 , no expense spared in the build ,about 11.5 comp. forged 60 pistons,floating pins Major headwork, Lump ported ,175 rollers , ALL BEARINGS COATED, THE LIST GOES ON ! I bought the DUI distributor, basically it sucks. First thing is some of the module screws were loose, and for the inline 6 they give you a 2" adaptor that goes on the end of the main shaft to reach the oil pump ,rather then having a dedicated shaft for this application, Now you have to carefully file the adapter on the one end so it fits TIGHT with no play and is then held in place with a tiny roll pin, you have to "V" out the recess but on an angle this is precision work and no room for any tolerance. . the slightest bit of play will cause the adapter to vibrate and damage the distributor gear, Beside other shit first Dyno pull was 366HP, We swapped out the DUI coil with an Accel coil and picked up 10 HP !! 3 times we did this. Ended up building my own distributor with parts I had , Never will I recommend DUI !!! and made another 9 HP !!! side by side it is exactly the same as an E-BAY special !!! That two piece distributor shaft not only stupid but was incorrectly machined , ebay HEI with a accel coil and MSD module beat the DUI IN HP, Quality and cost .

[@frankzito1660]

I ran 6.80s in the 1/8 with a fairly strong solid roller 11 to 1 327 in a vega with at th400 and a 4.56 12 bolt. Stock gm hei. Shifted at 7000 rpm. Absolutely bone stock distributor. Switched to a DUI and didn’t pick up any et or mph. Ran 38 degrees total on both.

[@SteveXNYC]

Since resistor type plugs actually “resist” some of the spark energy, non-resistor type plugs actually deliver a more powerful spark. It is for this reason that most racing plugs are non-resistor types. However, in most automotive applications, a resistor plug is required for proper vehicle operation.

[@doncroswe1179]

The experts in my area , told me to not use the vacuum advance at all , instead set the timing that they suggested, in my case it was 38° before top dead center ☆ my motor is a 440 mopar thats some what modified * headers, cam & such ☆ its mostly street driven and go's to the drag strip once a year ☆ When i go to cruise ins , people want to know why my vacuum advance is blocked off with a pastic plug ☆ i tell them, thats where where it runs the best 😊 , they usually walk away is disbelief ☆ however, these folks do not run their car's at the strip ☆ in ending,, i will say this, im completely satisfied with the with the performance of my car , street or strip 😊 thanks for listening ♡

[@joealbert7773]

I don't understand why the timing had to be reset when you connected the vacuum advance. Vacuum advance only adds timing under low load conditions (high vacuum). It has no effect on high load applications such as a dyno pull. The maximum timing under these conditions is controlled by the mechanical advance. The real purpose for vacuum advance is part throttle fuel economy. That's the way most vehicles are driven.

[@ABs70nova]

8 years and I literally have NEVER seen another sbc with the same heads/intake as me until now

[@jayleno5652]

i like their stuff DUI rev limiter live wires and mini VIP on ,y 355 7000 plus no issues and the vip was what made power over anything else i used

[@stoneyswolf]

These dizzys are a good deal. I didn't need the entire unit so I purchased there module.

[@docholliday6635]

Timing that's referred to total timing. Vacuum plus centrifuge, and built in..8 degrees built in. Then vac time and centrifuge advance.

[@robertmacpeek424]

@ 3:11 I'm confused. I've always brought cyl 1 to TDC on compression stroke first Then installed dist w/rotor pointing @ the "5:30" terminal (If your looking at an HEI cap w/the power, tach and ground connector @ 3 o'clock then this is the terminal just before the 6 o'clock position)

[@shelbyavant5081]

That's literally what they did.

[@pauljanssen2624]

You bring your engine up to 10 degrees before top dead center on the firing stroke either by watching the valve train or compression you'll see the trigger wheel on HEI is pointed citizens points lineup and you go a hair father that's when the spark will happen you can literally shut your engine within 1 to 2 degrees by this method you won't even have to re-time your engine I've built many engines with this method knowing where the distributors fire I really have to move them after checking with a timing light basically I learned it from timing VW engines and mg midgets always Prime the engines with a dummy distributor before you 🔥 them up and it's not hard to build a oil priming tank out of an empty R134 tank just have to weld A fitting on the bottom and put some oil in it and a cap with the Tire valve to pressurize the tank

[@susanhenderson2322]

Seems like lots of folks commenting on here dont understand base timing, totatiming advance and vacuum added timing

[@joshuamoore24_7]

It would be nice if some distributer company made a top for a hei rotor company made a computer controlled ignition box like the ones that are found on modern engines. Like Ford's and some other ones.

[@bkcrim5395]

They're a little expensive but progression ignition makes computer controlled dizzys that you time using a timing table on the computer

[@smokey05sierra22]

Where can I find a set headers shocker or split sockets 13/16 and 5/8"

[@JohnSmith-bx1mp]

A store.

[@Hot80s]

you failed to mention a small detail those nylon screws on the dizzy, very nice touch

[@REDZ28won]

Those nylon screw break and will strand you. Get steel screws so you wont get stranded!

[@dickeymoore4264]

Do all dui distributors come with a melonized gear for hyd roller camshafts?

[@dansmith6990]

2:53 watch

[@Mcheal2474]

If your rotor button is slightly off how will your engine run ??

[@rodolt2659]

It sounds like the main difference is the higher coil voltage and larger plug gap plus custom timing curve for the given engine setup. Timing curve really isnt a curve however its really just a rate of increase of advance per rpm increase or a slope. I would say its degrees/rpm. I suppose you could create a curve with progessive rate advance springs and or multuple springs of different weights combined. So take a stock HEI put High Perf Coil on it and larger plug gaps and proper advance springs you prettt much have created a DUI clone.

[@72troy455]

Pretty much, they ain't the only game in town.

[@walkingman9171]

Factory HEI was current limited to 60,000 volts and that's not how vacuum advance works. This is just a glorified commercial.

[@jerryvaughn9834]

Does anybody know for sure what MSD recomends. As far as plug. Gap msd distributer w/ al 6 box

[@davidwarland2680]

i have 6al-2 and use Brisk spark plugs, 3mm gap, huge (118.11 thou)

[@cjbert6790]

Msd is high voltage because it uses a capacitor. The downside is a short spark duration hence they use multiple sparks at idle speeds to make up for it.

[@sidecarbod1441]

I don't think you guys fully understand what the vac advance system is for or if you do it was not clear in your video. You have established that the engine wants 36 degrees at WOT and that is what it is always going to want. The vac system should be setup to add more timing above this figure of 36 degrees to allow extra advance when the throttle is just cracked open (regardless of the RPM), the extra advance allows for the fact that the flame speed is low when the VE of the engine is low. Your total timing may go up to something like 50 degrees but only under very light throttle settings. You guys seemed set up the vac system then pull a WOT run on the dyno, of course it is not going to make any difference with that sort of test.

[@hotrodray6802]

Well said. 👍👍👍

[@thomasbutcher4424]

Good luck racing with that setup!

[@ben54322]

This comments are gold. Thanks for explaining

[@walkingman9171]

Yes you are correct, he doesn't know what he's talking about with the vacuum advance.

[@aboutmyfathersbusiness8324]

Agreed; Vac Adv also keeps the engine cool in long parade idles.

[@scootergeorge9576]

Great video. I own a 1965 Ford Mustang that I installed a 302 Ford small block wih an HDI distributor. It is conected to the original ignition lead with a resistor wire behind the dash. 1.5 ohms or so. What is the best way to get pesk voltage to the distributor and peak performance? I was going to bypass the resistor wire (pink) but it's a pain to get to. Anoter idea was a relay actuated by the existing igniton power wire feding power directly from the battery. What do you recomend? If a relay, which one? Thanks and once again, great video.

[@timokuusela5794]

GM has different coils for the HEI. The standard one uses normal plug gap. The stronger one uses different plugs that have over 2 mm, about 0,08 gap. I used to have a Buick -84 with 307, and it had that coil and plugs from the factory. When the coil failed, I went with it to the local speed shop here in Finland, and the guy looked at the coil wires and said "oh, it is THAT coil" They are of different color or something. I have a Ford Taunus (Taunus not Taurus, google Ford Taunus -82) that used to have a Pinto type 1.6 L four in it. I put a 302 to it, but bought a Hei with the Ford style base, Ditched the Ford strange ignition system. One + wire and good to go.

[@1967davethewave]

I love the HEI. I run them on all my GM cars. But one thing that was wrong, most stock cars in the 1970's with HEI distributors had the spark plug gap set between .045 and .060. so setting your plugs at .045 was actually on the low side of what stock would have been.

[@shelbyavant5081]

Nope.

[@skywalkeraviation84]

Nope that .060 advice was rescinded by GM(they had all sorts of problems)… with HEI the standard is .045, but anything down to .035 will be ok and depending on setup could actually be better. That doesn’t go out the window with new high tech ignition, but it’s no longer the standard/hard fast rule.

[@1967davethewave]

@@skywalkeraviation84 I'd love to see a link to the TSB that shows GM "rescinded" the .060 spark plug gap. There are plenty of engines where .080 was the recommended gap. Just look at mid 70's 455 Olds, Pontiac 455 used .060 as did many others. It doesn't really matter what the recommendation is though, what matters is what works. I have raced for many years with an HEI and I always gap my plugs at around .060. And that's even on my 69 GTO which has 11.5 to 1 compression. As long as your wires, cap and rotor are in good shape and you have the voltage it works very well.

[@1967davethewave]

@@shelbyavant5081 What was the gap on GM cars with HEI distributors set at in the 1970's then?

[@shelbyavant5081]

@@1967davethewave They started at .060, and it was too much. Olds did try .080, and it was also too much. The componentry doesn't last with those gaps. Hell, .055 is a lot. That's why they changed everything to .035-.045 IN THE 70s, and that range hasn't changed in 40 years.

[@mtnman6278]

I was told when HEI came out in 74 they were using .060 on the plug gap and it was burning through the center of the rotor and going to ground through the dis. Shaft so they reduced gap to .045 if this is true you are talking going to over .050 to .055 on gap.

[@colehara]

Mountain Man You're right. I had that happen. I reduced the gap and it didn't happen again.

[@mtnman6278]

@@colehara yeah I just remember the gap was actually .060 and they reduced it to .045 after it was burning through. I was told this by my boss back in the late seventies when I worked in his shop

[@danielbrealey2924]

On a stock HEI this is true. These DUI ignitions have a much better coil and can create a much more intense spark, allowing you to open up the spark plug gap more than stock. The bigger the plug gap the nicer the engine will run at idle and part throttle. When your building forced induction engines and haven't replaced the ignition for something more powerful you find you need to decrease the plug gap so the spark doesn't get "blown out". The higher the cylinder pressure the more difficult it is for the spark to jump across. Reducing the plug gap solves the problem you face at WOT but at the cost of slight ignition stumble or a very slight miss fire at idle and part throttle...

[@mtnman6278]

@@danielbrealey2924 "blown out" meaning the spark wont happen Or wont jump?

[@fredmendez4837]

Some engines had gap up to .080....the 1974 olds 455c.i. used an .080 inch gap...in 74 most chevys sblock and bblock used .060 inch gap, and eventually went down to .045 i believe...and it was because ignition was not capable of firing over .060 gap...I remember it was causing ignition failures

[@philipmetzner7243]

You describe the function of the vacuum advance as if its connected to manifold vacuum but you used ported vacuum. There is already too much confusion about where to hook up the vacuum advance.

[@fredmendez4837]

Holley carbbhas ported vacuum and one ot two ports also ruun manifold vacuum...one of the side connectors i believe

[@whirlwind8825]

manifold vacuum to the distributor only ... wot timing should be set and then lock the distributor, small springs on the weights ... you want to launch advanced .. then taper off to mechanical timing all in at wot... and always use mechanical secondaries for better response

[@johnnydavis8351]

36*....??? kinda sounds heavy.... How does it respond to restarting when engine is up to temperature.... seems like something you could accomplish through Cam degree... Harmonic balancer tab typically only goes 20* or so

[@realdeathpony]

That's pretty normal for a mild SBC. They have made adjustable timing lights since 1920. Just a tab and balancer line.

[@cliffbennett3372]

Aren't you supposed to set Base timing with vaccum advance plugged off. Why set timing again?

[@paulpasternak2026]

Not a single tip.

[@chevyjones7818]

Man nun at all

[@earlbrown]

They did show that you need to adjust the distributor after hooking up to a PORTED vacuum source. (which is wrong and shows the throttle blades are open too far at idle) And they showed that after backing off on the timing, the car made the same power up top (which is also wrong due to backing off the distributor causes all the ignitions events after idle being retarded) So I guess that's something.

[@tomconner5067]

The plug gap! Sort of?

[@Joe-bb5hf]

Thanks

[@SmudgyContent]

Mine failed from DUI distributors, within a year… though they are great about backing their products they over nighted me another, they’re not meant for dailies I don’t think…

[@joen5332]

Does vacuum advance have anything to do with vacuum secondaries to open up the back barrels

[@ViewThis.]

I'm not sure I understand you're question, but I'll try to answer it: The two are not related. The vacuum that would open the back barrels is measured or "Seen" by what's flowing through the barrels themselves. The Vacuum for the distributor is seen below the barrels and serves a completely different purpose. One is above the throttle plates (back barrels), the other is below the throttle plates. If I'm wrong someone will come along and correct me.

[@michealurias3010]

I have a 350 chevy in a 1973 blazer , the motor is new with everything else on it and won't start please let me know what tut I am doing wrong. I am puzzled about cause I have been doing this for 55 yrs

[@aboutmyfathersbusiness8324]

Check for fuel, Check for spark. You may be getting spark but the distributor is 180 degrees out of sync. Many put it in what I call fake Top Dead Center.

[@jeffbraden78]

It aint got no gas in it

[@PatrickBaptist]

Gonna do this to my turbo stroke diesel.

[@danielbrealey2924]

Hahaha! I wonder how many people understood that was a joke...

[@PatrickBaptist]

@@danielbrealey2924 LOL, I'm surprised it took this long for anyone to respond to that LOL, take care buddy.

[@phillipchristensen2393]

Did it to my duramax... I can run e85 now!

[@jennymann3704]

DUI 😂 nice never heard of it. I'm glad my timing marks are gone

[@40HudsonV8]

Did I hear correctly this is a 604 cubic inch engine? I would have thought the stock horse power and tourqe numbers would have been higher.

[@ScrewHeadJuNgle]

Its not referring to c.i. its the last few digits of the crate engine part number.

[@moedog07]

ScrewHeadJuNgle Thanks for clearing that upa

[@stoneyswolf]

That's a small block the most Cid I know of right now in a small block is 454. I have a 406 myself but if I had a reason to do it over if stroke it to a 427.

[@user-cy4gy7zm7u]

its a part #88869604 race CT crate GM New engine 350cid 400hp

[@JAHISRAEL]

Yeah my 1970 Olds 455 has 500ftlbs torque and 425HP stock with standard ignition (but I am about to switch to a Summit Racing HEI )

[@tombryan5653]

Are you run racing fuel

[@ashadams3956]

Does the Chevy HEI NEED resistor or Non resistor spark plugs?? Can't really get a answer from anyone. hope you can shed some light on it for me

[@telocho]

Ashley Adams The resistor is only to reduce interference on the car radio, not for performance reasons.

[@danielbrealey2924]

Electronic ignition systems like a resistor type plug. The increased resistance actually increases the energy of the spark jumping the gap of the plug. This only works with an electronic ignition like a HEI as the system is able to create enough energy to make this more intense spark. If you use resistor type plugs on a points ignition it will burn out the points very quickly. The low energy spark created by points ignitions are due to the lower voltage on the primary side of the ignition (which is done to make the points last longer). Electronic ignitions use the full 12v and when the magnetic feild in the coil collapses it induces a bigger, more powerful spark to be created in the coil. Points ignitions systems work the same way, but with half the primary voltage- so they will never be able to create a big powerful spark like an electronic ignition. Hope that helps. By the way, I've been a qualified mechanic for 19 years- I'm not an internet know it all just incase you were wondering... Cheers

[@danielbrealey2924]

@@telocho Condensors are used to reduce electronic "noise" in the car's radio with some ignitions. Plugs don't have anything to do with that bro...

[@sunking2001]

I had a DUI in '97...is that the same thing you're yakking about?

[@sharonburns4788]

sunking2001 no,no .if you had a DUI you were drunk and arrested. Ha ha.

[@kainariylius392]

Too bad they don't fit on a tunnel ram intake.

[@dannypeacock3994]

what is the spark plug gap

[@kansascityshuffle8526]

Can see the bunch of wrench heads who patented the name DUI cackling all the way to the bank.

[@kCI251]

Oh, it's really a commercial for an HEI, not just tips.

[@hotrodray6802]

PD HEI is the best their is.... think not... go out into the real world.

[@hotrodray6802]

DUI means Davis Unified Ignition now produced by Performance Distributors.

[@OldAndGettingOlder]

Yep. It's a commercial. Not for HEI per se, but for a particular HEI distributor brand. I hardly call this a tip video.

[@Moparmaga-1]

Oh good, well what's the cubes ? Its sweet

[@jimdavidson5208]

Those garden hose wires are lovely LOL. Did you get those at Home Depot?

[@TheHorsepowerMonster]

Ha! The wires are pretty standard at 8.8 mm, but the sleeves to protect against contact from the headers do puff them up a bit.

[@larrycumbo2023]

I used a magneto never had a problem

[@melvinnewsome6821]

HEI originall required spark plug to be set at .080, I have been setting gap at .060 starting in 1974

[@utooberblooper]

0.035 to 0.045

[@Handlehandlebars]

How do these guys run a dyno yet dont know the purpose of vacuum advance.....such a confusing video. As mentioned below it supposed to add advance at low load high vacuum engine condition when an engine actually needs more timming...

[@danielbrealey2924]

Yep, your 100% correct.

[@Gettinbentoffroad]

Which is caused why? Cause the engine is running lean.

[@homefront3162]

yup

[@daveponder2754]

Yep that's how to get it "timmed" (sic) right.

[@terrypikaart4394]

blake hastings Your so right, like on a heavy atuomatic car when it shifts at part throttle and lower rpms.

[@jessebaldwin7297]

want a please all I want

[@walterstanfield3662]

604 sbc?

[@OldAndGettingOlder]

It's not displacement. This is a 350 engine. 604 is the last three digits in a part number (88869604). This is Chevy's CT400 circle track 400 HP create engine. There's also a 602; the CT350. Now you know.

[@walterstanfield3662]

Oh okay i gotcha thanks

[@jesusgomez9915]

😊😊

[@jdsimons6115]

604 crate engine... with TBI valve covers 😆👍

[@davidstjames_]

Yes! Similar were used on some other factory engines as well. Did you notice the two vents on the left side and none on the right side? It doesn't make sense.

[@poortouringhotwiregarage5617]

You can tell they are real mechanics by the liberal amount of duct tape

[@Pork-Chopper]

All this is wonderful n marvelous, cept' most street engines run between 2000 n 3000 rpm, Not, 6000 rpm. Street engines are better off with low down grunt at the lower rpm's for pulling n cruising, not at sky high rpm's which they hardly ever see, unless you're building the engine for racing. Properly setting up your drivetrain also will help to get the most out of your engine n maximize MPG...

[@Mal_ware_666]

It's perfect for people that have had a D.U.I

[@bigaparker1977]

Conveniently named the DUI LOL.

[@cargojorts3038]

Nice name lol

[@Syrus54]

lol... This "DUI" distributor only has 50kv, and you're talking like it's the Shit... My Normal HEI has 65kv, and I think it needs MORE.

[@jimdavidson5208]

Riiiiiiiiiiiight. LOL. 65kv what a joke. Lucky to get 40kv out of ANY HEI DUI what ever shit ignition.

[@mcozpda3392]

65kv ??? .. what brand ??? .. ????

[@donrutter6765]

I just bought a 65k distributor online on ebay, they are everywhere for $40 , I bought a set of 10mm wires to go with it for 30$. I cant wait to get this engine off the stand, and onto my running stand.

[@79huddy]

Don Rutter don't run it it will eat the teeth right off your cam they don't index for shit ask me how I know

[@johnwolf1475]

Your website is coming up as dangerous.. better have webmaster check it out

[@KGisthename]

Did you say that 604 makes 400 something hp? Thats so sad 😔

[@TheHorsepowerMonster]

It's a Chevy crate, that's what they make

[@KGisthename]

@@TheHorsepowerMonster That makes me sad. That thing is a behemoth and makes the same amount of power as my 383? Nice big heads too.

[@TheHorsepowerMonster]

@@KGisthename I think we might have some confusion. It isn't 604 cubic inches. GM calls it their 604 crate motor because that's the last three digits in the part number. (They also have a 602 crate where the only difference is cast iron cylinder heads.) It is a standard 350 cubic inch engine that's generally used for spec stock car racing classes.

[@KGisthename]

@@TheHorsepowerMonster gotchya!

[@KGisthename]

@@TheHorsepowerMonster thats not bad at all for a 350.

[@crawford323]

DUI, HEI, Ari? Not one person bothers to explain what they are.

[@ThisNThatGarage]

Did he really say HEI is weak????

[@earlbrown]

That's what you say when you make an ad for D.U.I pretending to be a 'tech' video. That's why they had to close the gaps on the plugs to show the stock unit can't light off 400hp. (which it can all day long). Otherwise, the two power curves would have most likely both fallen within the realm of tolerances. Did you also notice they had to move the distributor after hooking up to a PORTED vacuum source. Vacuum signal on that port at idle means the throttle blades are open too much. But, at the same time, they backed off on the distributor setting yet didn't lose any power up top???? Just fluff to sell D.U.I distributors. Nothing more.

[@classicskrt2422]

Not a single tip, just a bunch of specs in your engine setup. Thanks thi

[@cheapshedkits]

Really, a name like DUI???

[@earlbrown]

It stands for Davis Unified Ignition.

[@markbarnhill6300]

Dahh. !

[@jessebaldwin7297]

just add beryllium push rods and were gonna go some wear

[@mobilechief]

Can you drive drunk with it?

[@Moparmaga-1]

604 cubes & only 400 and some change in power #s

[@d-swank7599]

604 is the part number not the displacement

[@72troy455]

It's a 350ci SBC.

[@anthonyr1080]

Well it's a great commercial for the distributor but you learn absolutely nothing but let me explain something to you you don't use vacuum advance on the High Performance Engine it's for station wagon so when your wife floors it to pass somebody she don't burn up the engine cuz she's running cheap gas. Hi vacume hi advance ok so far low vacume less advance step on the gas and your vacume drops so does the advance see it ment. To save the engine not make power now cruise and the timing goes back up for gas mileage also when you let off the gas you will see it spike up to like 40 for a few seconds this prevents back fire I got a lot more but you chew on that for now

[@texasdoc68]

Wrong

[@KingJT80]

Anytime you drive at part throttle you need vacuum advance stop giving bad advice for street cars.

[@m.m.aautos6608]

Ouuuu wow nice fancy gm motor only making 9.6:1. Compression 😂😂😂 my 302 makes 9.11:1 comeplte stock internals . 😂

[@tabbott429]

None of this will matter when the fastest thing on the road is an EV.