NO BULL; how fast was a B-body 383 HP car compared to a GTO or a Chevelle SS 396 car?

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  1. oldbee

    oldbee FBBO Gold Member FBBO Gold Member

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    Correct me if I’m wrong but I think ‘Ma’ went with 2-bolt mains was because they were up inside the casting instead of hanging outside the skirts like GM’s?
     
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    • super-bee_ski

      super-bee_ski FBBO Gold Member FBBO Gold Member

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      Great to hear biomedtechguy, GREAT TO HEAR!
      Yeah, I know of their "shaky-reputation"

      But, just seeing the car in the video AND watching it perform is always a PLUS
       
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      • super-bee_ski

        super-bee_ski FBBO Gold Member FBBO Gold Member

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        Last edited: Jan 4, 2018
      • super-bee_ski

        super-bee_ski FBBO Gold Member FBBO Gold Member

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        Interesting quotes from: Hot Rodders


        1. Well, I think I'll start the shootout by drawing the MOPAR. In the first place, it's a big block, so the engine will be a lot stronger. Also, look at it dollar for dollar, the SBC has to be built up to get 383 cubic inches. The MOPAR starts there. The MOPAR has much better cooling, due to the full length water jackets in the block. You can mount inexpensive MOPAR 440 heads on it, giving it bigger valves so it can breathe better. As for sound, have you ever heard a MOPAR 383 running a high overlap cam? Way better than a SBC. Though my biggest argument for the MOPAR is, dollar for dollar, the MOPAR will end up with a lot more power. I realize this is presented as an opinion, but as I have said, my experience is only with MOPARs. If I've said anything wrong about the SBC, please correct me.

        2. I'm a Mopar guy, I think the best comparison would be the old raised block 383, not the newer B engine.
        Same bore, same stroke, both engines- are they not?

        The head design on each is very similar (rocker shafts versus studs doesn't make much difference IMO) and both engines respond much the same way to comparable mods IMO.

        The MoPar has a few pluses- front mount distributor, external oil pump, bigger stock valves, skirted block etc but the SBChev has lighter weight and a greater aftermarket.

        I would rather see the early 4.03 bore 3.75 stroke 383 Dodge used in the comparison, not the more familiar 4.25 bore 3.38 stroke 383 B engine....

        3. The Mopar 383 heads were the same as the 440 heads.

        Engine analyzer marginally favors the Mopar if all else is equal but the bore, stroke and rod length.

        Chevy:

        RPM···········2000····2500····3000····3500····4000 ····4500····5000····5500····6000····6500
        Brake_Tq······239·····309·····388·····425·····462· ····485·····487·····475·····446·····390
        Brake_HP······91.2····147·····222·····283·····352· ····415·····463·····497·····510·····483
        Exh_Pres······0.0·····.1······.1······.2······.3·· ····.4······.5······.6······.7······.7
        Int_Vacuum····.1······.1······.3······.4······.6·· ····.8······1.1·····1.3·····1.5·····1.6
        Vol_Eff_%·····64.6····72.7····84.6····89.8····97.0 ····102.8···105.2···105.4···103.4···99.0
        Actual_CFM····154·····216·····304·····376·····465· ····555·····630·····694·····741·····767
        Fuel_Flow·····56.3····79.1····111·····137·····170· ····203·····230·····254·····271·····280
        A/F_Mix_Qal···82.6····95.4····98.3····100.0···100.0· ··100.0···100.0···100.0···100.0···100.0
        BSFC··········.617····.538····.502····.485····.483 ····.488····.497····.510····.531····.580
        BSAC··········7.742···6.753···6.295···6.082···6.05 3···6.120···6.237···6.403···6.660···7.273
        Friction_HP···20······29······39······52······66·· ····84······105·····128·····155·····199
        Mach_#········.150····.187····.225····.262····.300 ····.337····.375····.412····.450····.487
        Piston_Spd····1250····1563····1875····2188····2500 ····2813····3125····3438····3750····4063
        Piston_Gs·····283·····442·····637·····867·····1133 ····1433····1770····2141····2548····2991
        Overlap_%VE···-4.2····-1.6····3.8·····2.7·····3.3·····3.9·····3.8·····3.4 ·····2.6·····.8
        Int_AvgVel····114·····143·····172·····200·····229· ····257·····286·····314·····343·····372
        In_InertiaPrs·.1······.4······1.1·····2.0·····2.9· ····3.6·····4.0·····4.0·····3.7·····3.3
        In_ResTunPrs··0.0·····0.0·····0.0·····0.0·····0.0· ····0.0·····0.0·····0.0·····0.0·····0.0
        Ex_AvgVel·····124·····155·····186·····217·····249· ····280·····311·····342·····373·····404
        ExTun_Prs·····.5······0.0·····-.6·····-.6·····-1.0····-1.7····-2.1····-2.2····-1.9····-1.6
        Lifter_Pump_UpNone····None····None····None····None ····None····None····None····None····None
        Spark_Adv·····28······29······29······30······31·· ····32······32······33······34······34


        Mopar:

        RPM···········2000····2500····3000····3500····4000 ····4500····5000····5500····6000····6500
        Brake_Tq······239·····309·····390·····428·····464· ····487·····489·····478·····451·····408
        Brake_HP······90.9····147·····223·····286·····353· ····417·····466·····500·····516·····505
        Exh_Pres······0.0·····.1······.1······.2······.3·· ····.4······.5······.6······.7······.7
        Int_Vacuum····.1······.1······.3······.4······.6·· ····.8······1.1·····1.3·····1.5·····1.6
        Vol_Eff_%·····64.0····72.2····84.4····89.9····96.8 ····102.6···105.1···105.3···103.5···99.2
        Actual_CFM····153·····215·····304·····377·····464· ····554·····630·····694·····742·····769
        Fuel_Flow·····55.8····78.7····111·····138·····170· ····202·····230·····254·····271·····281
        A/F_Mix_Qal···82.2····95.4····98.3····100.0···100.0· ··100.0···100.0···100.0···100.0···100.0
        BSFC··········.614····.535····.499····.482····.480 ····.485····.494····.507····.526····.556
        BSAC··········7.699···6.709···6.262···6.051···6.02 3···6.088···6.199···6.358···6.597···6.979
        Friction_HP···18······26······37······48······61·· ····79······99······121·····147·····174
        Mach_#········.150····.188····.225····.263····.300 ····.338····.375····.413····.450····.488
        Piston_Spd····1125····1406····1688····1969····2250 ····2531····2813····3094····3375····3656
        Piston_Gs·····243·····379·····546·····743·····970· ····1228····1516····1835····2184····2563
        Overlap_%VE···-4.2····-1.5····3.9·····3.1·····3.3·····3.9·····3.8·····3.4 ·····2.5·····.6
        Int_AvgVel····114·····143·····172·····200·····229· ····258·····286·····315·····343·····372
        In_InertiaPrs·.1······.4······1.1·····2.0·····2.9· ····3.6·····4.0·····4.0·····3.7·····3.3
        In_ResTunPrs··0.0·····0.0·····0.0·····0.0·····0.0· ····0.0·····0.0·····0.0·····0.0·····0.0
        Ex_AvgVel·····124·····155·····187·····218·····249· ····280·····311·····342·····373·····404
        ExTun_Prs·····.5······0.0·····-.6·····-.6·····-1.0····-1.7····-2.1····-2.2····-1.9····-1.6
        Lifter_Pump_UpNone····None····None····None····None ····None····None····None····None····None
        Spark_Adv·····29······30······31······32······32·· ····33······34······35······35······36
         
      • ksurfer2

        ksurfer2 Well-Known Member

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        Please excuse my ignorance....In this thread there are numerous references to "Day 2" and "Day 3" modifications. Can someone explain this for me please.
         
      • super-bee_ski

        super-bee_ski FBBO Gold Member FBBO Gold Member

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        Simply put:
        1. Day 1 is the day you purchased the car brand new....

        Typically, back in the day 'WE" would add 'MODs" within a short period of time after we purchased the cars.......
        A) Headers
        B) Bigger Holley
        C) Open air cleaner element if it didn't have one already
        D) Bigger tires in rear
        E) Jack up the Rear-end with Gabriel "Hi-Jackers" (Air Shocks)
        F) Cragar Super Sports, Cragar Keystone Klassics aftermarket wheels

        Day 2:
        More in depth, not necessarily on the 2nd day of ownership.....
        A). Hotter Cam
        B) Pull the heads, custom 3-angle valve job
        C) Thinner Head Gasket to increase the Compression Ratio (CR) OR Mill the Heads down for a smaller Quench in the combustion chamber (from 72 CC down to 64 CC)
        D) Re-Curve the distributor
        E) Change differential gearing to a numerically "higher" number (Lower Rear-End gear)
         
        Last edited: Jan 4, 2018
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        • YY1

          YY1 Well-Known Member

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          My "day 3" reference was because in 1990 it was a 20 year old car and several thousand days later than "day 2".
           
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          • lewtot184

            lewtot184 Well-Known Member

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            when the "b" engine was designed back in the mid '50's a 4 bolt main block was unheard of. keep in mind that a 300hp engine was the exception. ford went to cross bolts in '64 when power was closing in on 500hp (y-blocks are cross bolted) and Chrysler did the same to hemis because 2 bolts were unreliable in the 550-600hp range. chevy did the 4 bolt main on the rat motors, I believe in '65, probably because the '63 427 nascar engine wouldn't hold up with the power increases. in the late '50's up to the '60's fabricated girdles were used on blowen small block chevy and early hemis v blocks because 2 bolts couldn't hold the power.
             
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            • super-bee_ski

              super-bee_ski FBBO Gold Member FBBO Gold Member

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              Hi lewtot184!
              I "listen" and respect you and your info.
              All I know is:
              Take apart and build a few Pontiac 389/400/455s and then build up a 383 HP like I did in 2002
              WHEW!
              BIG DIFFERENCE!T
              The Pontiac blocks seemed like TOYs
               
            • lewtot184

              lewtot184 Well-Known Member

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              something I don't like about Pontiacs is cast rods and cheap internal parts; but there were good Pontiac parts made, but the average engine didn't have them. one advantage that mopar had was steel cranks and rods even in slant sixes (until the '70's rolled around). a lot of small block chevies didn't have steel parts. mopar did put money in their drivetrains but at the detriment to bodies. another thing to keep in mind is that back in the muscle car era only about 10% of the cars were performance orientated. bread and butter mopar muscle cars had 50,000 mile warranties; some gm's were only 12,000 miles. a lot to look at here.
               
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              • biomedtechguy

                biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

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                The 421 in the GTO has 4 bolt mains, but a cast iron "armasteel" crank. 4 bolt mains maybe because of the non-skirted block on the Pontiac as suggested?
                 
              • BeeKool

                BeeKool Well-Known Member

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                20171205_082241.jpg
                This edition of Car Craft was a good read.
                Explained the pros and cons of Poncho.
                Explained the switch from 389/421/428 to 400 to 455
                Heads cranks ect.
                IIRC the early year 400s were the best to build on because of the wider of the crank journals.
                Gotta love Ponchos, the GM product that cost as much as a Chrysler to restore

                That being said, the car on the cover would be much more handsome if it were a 64 tri-power. Lol
                 
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                • Photon440

                  Photon440 Well-Known Member

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                  Unless a dealer or owner shoved it in, there weren't 421 GTOs. Not as an option anyway...we know about the two that Jim Wangers built in 1964 so that magazine tests would look better in a comparison to the Ferrari GTO. https://history.gmheritagecenter.com/wiki/index.php/1964_Pontiac_GTO_Royal_Bobcat
                   
                • philcollins

                  philcollins FBBO Gold Member FBBO Gold Member

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                  Not 383 but my 1972 RR 400 was much faster that my freind 1972 GTO 400. Both stock, automatic.
                   
                • biomedtechguy

                  biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

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                  I do...
                  EDITED to suit mine and my wife's opinion, and choice. :)
                   
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                  • biomedtechguy

                    biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

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                    I had a steep but rapid climb up the Pontiac learning curve. Jim Wangers was nice enough to sign a pic of my wife's GTO Royal Bobcat tribute. Her car's PHS documentation tells the perfect "story" of what a Bobcatted car could be. Buy a 389 4bbl, get your ass handed to you one too many times, go to Royal and say "Give me the full performance upgrade". Get an October 1965 date coded 421 Tri-power shoved under the hood-which you don't pop, or maybe flash for big money-no way really to tell it's not a 389 without looking at the block casting number under the car...Maybe just say you swapped out the 4bbl for a Tri-power.
                    Line em up and show them your tailights!
                     
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                    • biomedtechguy

                      biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

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                      In the mountains near Pigeon Forge.
                      20170603_203140.jpg
                       
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                      • wagonman

                        wagonman Well-Known Member

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                        My good buddy recently got done with a 70 GTO 455 HO project. When I asked about the engine rebuild and the internals he said all was kept stock. I told him he should have upgraded the rods from the Armasteel cast to an aftermarket I or H beam. Yeah they are a lower RPM grunt motor but who wants to chance slinging one out the side of a #s matching car?? Anyway I remember Pontiac had a problem at the factory of keeping the good forged Super Duty in stock. Seems like the workers knew their worth and would take one piece at a time ( que Johnny Cash ). The only other Forged Pontiac rod came in the rare SD 455 circa 74 in the T/A cars. Good under rated engine that could really scream with work. His engine is still going strong with Lots of abuse. So what do I know? MEH. His machinist says they are good to 500 HP. Really? Eddy alluminum heads and a roller cam and a TKO with no missed 3rd gear shifts. Not me better safe than sorry. Enough about Pontiacs.
                         
                      • biomedtechguy

                        biomedtechguy Accelerati Rapidus Maximus FBBO Gold Member

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                        73, 74 HO or SD. Cam, carb, COMPRESSION and you had a SERIOUSLY competitive ride!
                         
                      • lewtot184

                        lewtot184 Well-Known Member

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                        I used to live a couple of miles from high school so more times than not i'd try to hitch a ride to school. there used to be a guy who'd pick me up with a '62 impala SS 409hp/409 4spd. it was 8 barrels open all the way to my drop off point! I was a somewhat shy kid and never said a word, just soaked it up. I wouldn't have traded those moments for a ride on the space shuttle. fast forward about a year and a friend had just graduated from high school. he was an only child and his grand parents bought him a new '65 tri-power 4spd GTO (this was like giving a kid a hand grenade to play with). there's hasn't been a sound any sweeter than those 3 rochesters at WOT!. long before I could drive I always looked at my brothers hot rod magazines and eyeballed all the engine stuff. I was stuck on multi-carbs before I could drive and still will be when I die.
                         
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