Holley 750 cfm, 4150, double pumper with mechanical secondaries and elec-choke

Discussion in 'Tri Shield Performance' started by VET, May 6, 2023.

  1. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    Stock converter should be fine with that cam. If you really want to wake up the motor, one of Jim Weise's 9.5" converters would be the ticket. Maybe it already has a converter in it?

    Torque converter replacement is only really necessary when you install a cam that raises the power range of the engine enough where the stock converter stalls too low. The best results are obtained when the converter is custom built for the engine and car. Engine torque, car weight, and gearing all affect stall speed.


    Last edited: May 10, 2023
  2. VET

    VET Navy Vet

    Wow, Jim helped me with the mystery of converters. I have no clue how they work.

    Based on your recommendation, I may stick with my standard Buick converter.
    I'am sure you know GSJoe in Ohio. He did the restoration on my car back in 2010 (way before I owned this Buick).
    However, he did have the TH400, BA trans rebuilt.
    The person who purchased the car in 2015 had a shift kit installed and I have to say, I have never experienced an automatic shift as quickly as this one does.
    When it shifts into second, it chirps the tires.

    I'am picking up my car from some work mods I had done in 18, May. I need time to see how it performs before I go off an buy one of Jim's converters.

    At this point, i'am not sure I have the HP power to justify high performance converter.

    I will revisit the converter option after I see what level of power my Buick will make.

    I'am still thinking about running it on a Dyno chassis to see what performance numbers I get. However, the engine is an old rebuild, maybe 2012, with only 3,500 miles on it but i'am afraid I might hurt the engine on the Dyno since it's not a fresh rebuild.

    Thank you very much for turning me onto Jim Weise.

    I can't begin to tell you how fortunate I am for someone of your automotive experience helping me out. Regards Vet
  3. VET

    VET Navy Vet

    Question for all you Buick lovers out there.

    I was just looking at all the hype of the E3 Diamond fire spark plug advertised.

    What's the deal, this plug any good????

    I'am running the Delco R45TS in my GS 455. I just had an MSD system installed to help prevent detonation issues I was experiencing. Everything seems to be working good during the engine test phase. I pick up my car from the shop in about 20 days.

    The E3 got my attention because of the manufactured claims. I'am not inclined to believe the manufacture until I hear what the Buick users of this plug have to say.

    Thanks in advance for your advice and experience with this plug.
    Regards, Vet (Navy)
  4. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    E3 spark plugs are no better than anything else. It's all hype to me. IMO, the electrodes just shroud the spark. I like NGK plugs. The UR-5 is a projected nose plug with a wider heat range. It's a great all around plug, and cooler for engines that are modified.



    I use the FR-5. It's equivalent to the UR-5, but has a flat seat and gasket for use in aluminum heads.
  5. VET

    VET Navy Vet

    Thank you, I though the E3 plug was all hype...

    I'am considering the UR-5, I want to pull the Delco's out after running them for 500 miles to see what they look like.

    If I need a colder plug, I will change to the UR-5's.

    Thanks for the tip.
  6. Mark Demko

    Mark Demko Well-Known Member

    I run an 850 AED on my 350, it loves it.
    Vacuum secondary carbs SUCK!
    Mart likes this.
  7. VET

    VET Navy Vet

    Mark, I just viewed an episode of Engine Masters where they compared a Mechanical Secondary Carb to a Vacuum Secondary Carb.

    The Mechanical Secondary Carb won hands down. They showed the performance on a Dyno and the power of the Mechanical is far greater then
    the Vacuum Carb.

    The big advantage of the mechanical is it's a double pumper. The secondary pumper really makes this carb really strong at the top end.

    As far as your 850 AED on a 350 goes, I'm blown away the 350 could take that huge size carb.

    Makes me want to put an 850 on my 455 GS. Vet
    Mark Demko likes this.
  8. Jeremy Zepnick

    Jeremy Zepnick STEELMAN

    The carb I have is a double pumper, vacuum secondary...works great!
  9. Mark Demko

    Mark Demko Well-Known Member

    I would for sure put at least an 850 on your 455 if it’s not stock.
    The 850 on my 350 is seamless in operation, no hesitation, I can idle all day and not foul plugs, throttle response is spot on.
    I’m set up like Larry, I can swap between my Q-Jet and my AED.
    I use the AED for the track, I couldn’t tune out the big bog in the Q-Jet when leaving the line with the SP3, with the dual plane Stage 1 intake the Q-Jet was awesome!
    Even on the highway at 70 mph (‘bout 3000 rpm) I’d floor it and the Q-Jet would hesitate. I honestly believe the double pumper fixed it with the secondary shot of fuel.
    The 850 cfm I wanted so not to leave anything on the table WOT wise, I’m sure I’m not using that much air, but it was fun to see if the 350 liked it.
    Chevy people say “you’ll loose low end with a single plane, 850 carb is too big”
    BS, not with a Buick 350:p
    I still do a 1.9 60’ with 3.42 gears:p:p
  10. VET

    VET Navy Vet

    Just read your comments, all I can say is WoW. That must be one bad Buick 350.

    My 455 GS is not stock but it's not crazy either, here are the specs.
    When I bought the Buick, some performance mods were already done. Some mods were never disclosed to me.
    (1) Port matched.
    (2) Comp Hydraulic Cam that's has more powerful than the original Stage 1 Cam.
    (3) Has Stage 1 heads.
    (4) I just had a full MSD ignition system installed.
    (5) Bored .030 over.
    (6) High compression pistons were installed but not disclosed to me and I have no idea what aftermarket brand pistons they are.
    I've looked for them on-line but can't find the exact piston (I had pics taken with a bore scope).
    I have no idea what the compression ratio is, but I ran into detonation issues that are now resolved by adding a HD clutch fan (better cooling) and adding an MSD ignition system. I had a compression test done and the compression averages 180 psi, pretty impressive I think.
    (7) The TH400 (BA) trans has a shift kit installed, another item not disclosed to me. It shifts faster than any standard auto trans I have ever run before.
    (8) Here's the strange item, this Buick has a 2.93 differential BUT, is a posi. I have the build sheet for this car and it came with an open 2.93. SO, WHO tries to build a performance car with a highway gear????

    Just so you know, I've been out of the performance cars for a very long time, family and job go into the way plus money (or lack of) is also an issue. Now I'm retired, saved some money for a GS BB.

    I've mostly been a SB chevy guy. One of my first cars was a 1956 Chevy Belair. Very fast in the day, 327, 365 HP, modified with an Offenhauser low profile tunnel ram manifold (same as the 302 Z28 used). 30/30 solid lifter Corvette Cam. T-10 4 speed and headman headers and a 650 Spreadbore double pumper Holley and Mallory ignition system. Made about 400HP.

    My father was a huge Buick fan, first car I learned to drive was his 1964 Wildcat 425 Buick. Did I say I was only 15?

    I bought my first automotive part, two new rear tires for his Buick. I was banned from driving the Buick. Bad day.

    I'm now 74 and bought my 1970 GS 455 back in May of 2021 and also joined the V8 Buick forum.
    My wife thinks I 'am trying to be 19 again, Ha, way to late for that.

    I just got the Buick out of some upgrades from a local restoration shop (18 months of waiting for parts mostly).

    What a BLAST this car is, Yaa. Can't wait to get more driving time on it.

    Mark Demko likes this.
  11. Mark Demko

    Mark Demko Well-Known Member

    Thank you, she runs pretty respectable considering the 3.42 gear and full options.
    I’m still 18 myself, I have 40 year’s experience at it, LOLOLOL
    FLGS400 and Brett Slater like this.
  12. VET

    VET Navy Vet

    OK, you win. Your 350 is packed with High Performance goodies.

    11.1, you run that on pump gas???

    I got on the AED web site, wow, I'm impressed with their carb products. Looks like they don't make any carbs with chokes.
    I live in northern Virginia, and I need a choke. it's gets cold here.

    13.40 et with a 350 and a heavy Buick, that's awesome. That's faster than a lot of stock 455 Stage 1's.

    Nice build. My GS 455 can't run with you.
    Mark Demko likes this.
  13. Mark Demko

    Mark Demko Well-Known Member

    Lolol, thanks again!
    Yes 11 to 1 on 93 octane.
    My theory on why I don’t have detonation issues is mostly from my torque converter, it’s a JW 9.5” converter, it stalls about 3000, flashes to 32/3500 the engine never really sees a big load, the car drives like a near stock converter, JW’s converters are magic:p
    I run 34/36 total timing. My initial is around 18.
    Larry suggested putting on 5 gals of race gas for the track as insurance against detonation.
    The AED carbs are nice, the have more tuning than I have ability LOLOLOL.
    Larry has an AED, that’s why I bought one verses a regular Holley 850.
    AED’s have no choke as you’ve noticed, if you can two foot it for a couple minutes while the engine warms up, it’s not bad:cool:
  14. VET

    VET Navy Vet

    Larry is a very smart guy, knows are the HP tricks.
    I'm learning fast to listen to what he has to say. Can't beat experience.

    You're pretty smart too. Getting a Buick 350 SB to run that fast is quite an accomplishment.

    I just had to get an HD clutch fan because my water temp was getting on the high side and it worked great.

    But, this caused a bad side-effect, the driver's compartment now sounds like an airplane, driving me nuts.

    I'm thinking about switching to duel electrical fans to keep the noise down. I also had sound deadening material installed in the floors during the renovation process. But the clutch fan noise still came through. I hope the electrical fans work, because this 455 really heats up on a hot day.

    Mark Demko likes this.
  15. Mark Demko

    Mark Demko Well-Known Member

    Yes, Larry is a knowledgeable guy, he’s also a very nice person;)
    A lot of my success with getting my 350 to run as strong as it does I owe to Larry and others on here, we share knowledge and experience, that’s what makes Buick people on this board really special!!
    On your fan and cooling, switch to the standard duty fan clutch, the heavy duty keeps the fan engaged too often.
    Make sure you have your fan shroud installed and your radiator is clean.
    On electric fans, unless your willing to upgrade your alternator, wiring, add relays and such there’s NOT any advantage to electric fans other than space saving and packaging, they DO NOT cool better than your engine driven fan contrary to popular belief, the ONLY reason the OEMs use electric fans is because an engine driven fan won’t fit, an engine driven fan moves WAAAAAAY more air than an electric one.
  16. VET

    VET Navy Vet

    Mark, here is my delima.

    My original clutch fan wouldn't cool down the water temp enough in traffic. I live 10 miles south of Washington DC, we get a ton of traffic.

    The shop installed the HD clutch fan and it does a fantastic job. However, it is really noisy.

    My thinking is, maybe an electric fan (duel fans) might cut down the noise?

    Back in the day (1972) I installed a flex fan on my 56 chevy and it did a great job of cooling down the water temp and it wasn't loud either.

    Maybe, I should bolt a flex fan onto my new HD clutch? I wonder if anybody has done this before.

    I love my car, but the fan noise is really bad. What a delima!

    Got any ideas????

  17. Mark Demko

    Mark Demko Well-Known Member

    Exactly how hot was it getting in traffic?
    You have aftermarket gauges yes?
  18. Mark Demko

    Mark Demko Well-Known Member

    I wouldn’t be concerned until about 22o degrees, BUT if the temp stabilizes at whatever temp it creeps to in traffic then comes down once you start moving, I’d say it’s ok.
    If it continues creeping after moving then it’s a radiator issue
  19. VET

    VET Navy Vet

    I had a Dokota gages installed, I love this setup.

    The water temp in traffic was 190 and going a little higher. Made me very nervous. O ya, A/C was running too.
    I have a 160 thermostat in the Buick.

    This is my first BB Buick, so I don't know a lot about how they react to hot weather and higher water temps.

    I also bought a new HD L1 alternator with a ton of amps. My original 1970 alternator would support recharging the battery when the A/C was running.

    I know you can't see the original clutch fan very well in this pic. Also, I changed out the A/C for a modern A/C unit. The original was toast.


    Mark Demko likes this.
  20. VET

    VET Navy Vet

    Mark, I have an appointment with my Tax lady.

    I will check latter today to see any responses you sent me. Thanks VET (Go Navy
    Mark Demko likes this.

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