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Straight 8 Buick Questions

Discussion in 'The Hokey Ass Message Board' started by chuckspeed, Dec 1, 2005.

  1. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    Gang -

    Being a car slut and all (I want to love them - all of them), my attention has swung over to GM turret tops as of late - specifically the late 30's straight 8 valve-in-head Buicks.

    I've been doing quite a bit of research on them - and they're pretty intriguing. Torque tube driveline, synchro trans, vacuum assist shifting, independent front suspension - lots of neat stuff to start with.

    But what really floats my boat are the large displacement, long-stroke, straight 8 motor. Damned thing appears to be built like a brick shithouse - and had some interesting features available - like Compound Carburetion. HP ranged from 107 for the 248 single carbie unit to 165 for a high-comp, dual carbed 320.

    It seems like it would be possible to build up one of these grand old dames so that they generate a fair amount of torque. Granted, you're never gonna spool up a longstroker much past 4 grand - but that's the attraction! Motor makes max torque only a few hundred RPM's off of idle, damned near.

    So - does anyone have experience with the following:

    a) refitting Compound Carburetion to an earlier (1937) motor
    b) non-stock cam grinds in the 248
    c) boring the 248
    d) piston swap/head milling for increased compression
    e) refitting later model conrods for modern bearing inserts (as opposed to babbiting)
    f) Head work - porting, valvetrain, et al.
    g) exhaust system upgrades, such as a custom header
    h) and the biggie - anyone attempt supercharging? Crank's got diesel-sized journals - does the material spec hold up to forced induction?

    No offense to the bowtie gang, but dropping a SBC in is about as exciting as dry white toast, IMHO. Gotta do something *different*...

    thanks in advance,

    Chuck.
     
  2. InjectorTim
    Joined: Oct 2, 2003
    Posts: 2,241

    InjectorTim
    Member

    I've got a factory dual carb setup for sale.
     
  3. HEATHEN
    Joined: Nov 22, 2005
    Posts: 8,583

    HEATHEN
    Member
    from SIDNEY, NY

    A '37 engine will accept the '41-'42 dual setup with no problems, and the '49-'53 insert rods are a bolt in as well. If you're into the 320s, try to find a '52 Roadmaster and steal the one year only 4 bbl. intake off it. I saw a small ad in the back pages of a 1955 Hot Rod for tubing headers for straight Buicks, but have never seen them in the flesh. If you run across a Mallory distributor with a "189" number on the tag, grab it!
     
  4. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    thanks!

    I knew the later conrods were a bolt-in; are they strong enough to take the pressure of forced induction?

    FYI - Howard and Isky both made performance cams with bigger lifts and longer durations - I'm hoping that Isky will do a grind if I supply them with a core.

    As for headers - I REALLY want to take a whack at building my own. After doing this for nearly 30 years, I'm ready to design my own set of longtube step headers to maximize low end torque - think double tri-y's; 8-4-2's.

    I think that a straight 8 with a custom chrome header, chrome valve cover, chrome dual carb intake, chrome plug wire cover and chrome tappet cover would look like a piece of serious eye candy!
     

  5. 50Fraud
    Joined: May 6, 2001
    Posts: 10,101

    50Fraud
    Member

    When I was a kid in the early '50s, old Buicks were right up there with Olds V8s for quickest production car honors. Best performance choice were '37 Century coupes. With some tweaking they would turn over 90 at the drags, and had torque enough to make the front wheels leave the ground on the 2nd gear shift!

    Among the aftermarket parts available for them was one of the all-time wild looking induction systems: the Howard 5-carburetor log manifold!
     
  6. 50Fraud
    Joined: May 6, 2001
    Posts: 10,101

    50Fraud
    Member

    The only blown S8 Buick I'm aware of was Mark Dees' '41 Century sedanette, running a McCulloch blower from a Kaiser Dragon (!!). I was interested in acquiring from Mark's estate, but it got away before I connected. I understood that it ran, but I don't know how well.

    Re S8 headers: several years ago I saw a '32 coupe running at El Mirage with a Buick engine and a spectacular basket-of-snakes header. Maybe Elmo Rodge would know who that is, and you might want to have a look at it?
     
  7. leadsleadolds
    Joined: Jun 7, 2004
    Posts: 1,817

    leadsleadolds
    Member

    There is a book on hopping them up
    California Bill's Chevrolet GMC & Buick Speed Manual

    Hot Rod and Custom Supply has them in there catalog
     
  8. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    50 fraud -

    thanks!

    I'd kinda figured a well-tuned VIH S8 was good for at least 350 ft-lbs of torque, and one with forced induction could whip out 500 flt-lbs at the flywheel.

    As I do the research, the rate limiting event in these motors (aside from ring speed and frictional losses) seems to be the siamesed intake port configuration. Forced induction would overcome the static pressure limitations imposed by the siamesed port - literally 'forcing' the engine to breathe. Seems like 10# of boost would make for a nice snarky motor that idled like a stocker, but kicked it down low where it counts!

    I've located a solid '37 slantback sedan not far from where I live. The 'look' of the slant really floats my boat; if I can get one to roll out with modern traffic then I'll be one happy camper!
     
  9. Jdee
    Joined: Feb 19, 2002
    Posts: 485

    Jdee
    Member

  10. sojerscraper
    Joined: Nov 12, 2005
    Posts: 214

    sojerscraper
    Member

    good stuff guys - i have a 51 with a 263 & have yet to tear it apart. i have a ton of hot rod mags from the 50s & 60s & there were quite a few buick straight 8 slingshot dragsters back in the day. i agree, that intake/exhaust manifold setup really gets me thinking about a crazy custom setup made from some bent up tubing.
     
  11. chub chub
    Joined: Aug 15, 2004
    Posts: 289

    chub chub
    Member

  12. fatassbuick
    Joined: Jul 6, 2001
    Posts: 989

    fatassbuick
    Member

    You might want to look up Broman or Scotch..they've gotten into these things pretty deep. I know you can mill the hell out of the head for more compression, someone's stuck bigger valves in them, intakes are basic and can be made, as TP did (I had an Edmunds 2x2 on my 263). I'd LOVE to see one do in the 90s at the drags naturally aspirated (shit, even blown for that matter).

    Also look at www.uncommonengineering.com as they have a Hudson with a blower setup and could probably talk to you about it.
     
  13. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    Thanks for all the great info, guys!

    Yah, I'm aware of uncommon; was thinking hard about a husdon build but the bodies are in such stanky condition after 55+ years that the project just seems like its a bit too much. Besides - If I get a turret-top, a frame off resto ain't all that hard to do on account of everything can be unbolted, dipped, welded, and hammered at shop bench height. It's nice to work on one panel at a time!

    Back to the straight 8 motor...

    it would be very cool to pipe up a driver's side octopus. I've got three thoughts on that...

    1) OEM Compound Carburetion manifold - for the 'look'.
    2) Four constant velocity M/C carbs on 10" runners; tune it with a jap bike carb stick. CV carbs alleviate much of the throttle response/idle quality issues, as the motor takes only as much air as it needs - regardless of throttle position. Kinda like cheap-ass fuel injection.
    3) A pair of custom-bent manifolds holding up a pair of Weber side-drafts.

    Any one of these combos will allow mondo air flow into the motor; it's just a matter of whether the motor will handle it. I've got a ton of the old HR's from the early to mid 50's, and a significant number of the really serious mills ran side-draft carbies, so there's nothing wrong with either #2 or #3 from a vintage speedmill standpoint.

    Having said all of that, the real rate-limiting event is to make power without having to spool the snot outta the motor. The solution just SCREAMS centrifugal supercharger! With a Paxton turning *about* 10# of boost, a properly prepped S8 should be good for 250-ish HP and nearly 500 ft-lbs of torque, methinks. If it's possible to adapt a Tremec TKO to the motor and retain the stock 4.40:1 gear ratio, then a 70 year-old motor *should* be able to trip the lights well over 90 MPH - hell, a reasonable goal would be triple digits and a high-14 trap!

    A turbo ain't the right sort of power adder for this kinda motor, 'cause they like a few RPM's B4 they make boost. Turbos are happier on motors that rev; a slow roller like the Buick 8 needs to be makin' torque like a diesel - almost all of it at 1500-1800 RPM.

    A 70 year old blown octopus. Damn.
     
  14. fatassbuick
    Joined: Jul 6, 2001
    Posts: 989

    fatassbuick
    Member

    I think that 10# may be too much for the cast pistons and flimsy (and VEEERY long) crank. I wouldn't suggest over 6# even with a fresh rebuild of stocko stuff. Lemme look on my old shit to see what articles I have on hopping up these things and I'll email you some stuff.
     
  15. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    that was my question h) from above - will the crank take the heat? Journals are big (bigger than BB chevy) journals, so that's not an issue; motor's got five main bearings; if they can get 300 HP outta a three main bearing flattie, then there's enough surface area to maintain hydrodynamic lubrication at forced induction pressures - I think. The other issue would be crank whip - I was hoping that low rotational speeds would mitigate the whip.

    I agree on the pistons; either an aftermarket cross reference to a modern piston would be needed, or a set of custom pistons fabbed to spec.

    anything you can get man - I'll read it! thanks!
     
  16. fatassbuick
    Joined: Jul 6, 2001
    Posts: 989

    fatassbuick
    Member

    Wulp, about yer fancy hydrodynamo stuff at forced infection...I know the old farts that took their 320+ cid I8 Buick out to Bonneville a couple of years ago busted 4130 cranks at $10k a pop, and that's with a 4bbl. and home made header. They also put BBC rods on it, did some weird stuff to the head, had a cam ground...you know the deal.

    Well, I don't know all that first hand, just from the magazines and some folks on here. It goes to figure that if the journals are larger than a BBC, but the crank is a lot longer, the harmonics will have as much or more of an effect (no harmonic balancer to speak of on the I8, either!), as well as the torque bending the thing all over the place, the goofy intake manifolds that tend to run the outer cylinders leaner and the inner ones richer, somewhat poor breathing, etc, etc.

    Basically, your enthusiasm is great, but I wouldn't expect too much from 70 year old inline technology except fun. I'll look on some old CDs in the next few days...moving screwed me up pretty bad...
     
  17. Broman
    Joined: Jan 31, 2002
    Posts: 1,487

    Broman
    Member
    from an Island

    I'm here...

    look at this link and become a worshiper...our arms are open and we won't make you clean your room and cut your hair. Join us and freedom is yours to take.

    http://www.jalopyjournal.com/forum/showthread.php?t=25465&highlight=Straight


    Please take a look at some of the links that are posted in that page - I think a couple go back to the old HAMB, which is cool and it all pertains to the enjoyment of our big fat inline eights.....

    Speaking of inlines....did you try www.inliners.com ?
     
  18. Broman
    Joined: Jan 31, 2002
    Posts: 1,487

    Broman
    Member
    from an Island

    Ahh I just went the inliners web site - they are changing it so it's not up now. Used to be a forum there too. I was at a car show once and there were a bunch of the guys there trying to get me to join their club. Well first they started BEGGING me not to pull the I8 and put in a SBC......I laughed out loud.

    They have a good thing going though it is mostly geared towards the Jimmy sixes and the more popular inliners, but they/we were all pretty like minded. I thought I might give 'em a heart attack if I told them about this place. I was affraid they'd waltz in thinking they could just blurt out whatever,,,,well the HAMB was different then.....
     
  19. Jai
    Joined: Apr 16, 2005
    Posts: 90

    Jai
    Member
    from Dallas, Tx

    here's another inliners site....

    http://www.inliners.org/

    I aso just have to chime in about how giggly I've been over all of the I8 talk lately. Between Scotch, Bowman, and FAB, i have been reeling with ideas about what I want to do with my 263.

    And I have been pining for Tims dual carb setup ever since I saw it. I can't believe no ones snatched it up yet. If I weren't piss poor I would have pm'ed on it weeks ago....

    Thanks fellas, for making a girl giddy again!! :D
     
  20. Jai
    Joined: Apr 16, 2005
    Posts: 90

    Jai
    Member
    from Dallas, Tx

    here's another inliners site....

    http://www.inliners.org/

    They have loads of useful info on the boards there too.

    I also just have to chime in about how giggly I've been over all of the I8 talk lately. Between Scotch, Bowman, and FAB, i have been reeling with ideas about what I want to do with my 263.

    And I have been pining for Tims dual carb setup ever since I saw it. I can't believe no ones snatched it up yet. If I weren't piss poor I would have pm'ed on it weeks ago....

    Thanks fellas, for making a girl giddy again!! :D
     
  21. Jai
    Joined: Apr 16, 2005
    Posts: 90

    Jai
    Member
    from Dallas, Tx

    NOOOOOOOOOOOOOOOOO!!!!!!

    I double posted!!!!!!!!!!!

    Karn sarn frickle framness bloody farghen piece of......
     
  22. fatassbuick
    Joined: Jul 6, 2001
    Posts: 989

    fatassbuick
    Member

    I called Don Montgomery "George" in that Scotch thread. What a dork.

    Where in the hell is Scotch and his Super 8, anyways?

    BTW, Isky and Howard I'm pretty sure will grind you a cam (weld up and old one and grind it down), but Moon has an old fart that used to do I8 cams and knows a good grind for them. I know of two people that got 'em from Moon. The price wasn't too bad, either..like around $250 for cam and lifters seems like.
     
  23. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    very,very,very good thread!

    Answered a bunch of questions I had about what could be done...Thanks!
     
  24. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    This is the sorta discussion I need to roll around the idea, man - thanks!

    Back in the day when I thought I was gonna end up designing powertrains for Ford, I spent a gajillion hours in the basement of Lawrence Tech poring over old SAE papers on engine theory and design; that's why I get all techie. The Marmon engineers had the best shit, FWIW.

    Anyway...

    I've had some experience with LSR engines - they're a bitch to design, as a normally aspirated engine has to be designed to develop about 15% more HP at sea level to compensate for Bonneville altitude. When you're designing for N/A - the easiest way to make the HP to push the lumpy brick of a body thru the air is to spin the motor faster.

    While I know *nothing* about the S8 LSR motor - when I did the build sheet for a pushrod OHV LSR motor, the requirement was a 100% increase in HP at sea level and a 34% increase in rotational speed. The motor was originally designed to live at 5600 RPM; the re-design necessitated life at 7500 RPM.

    Inertial loading is follows a logrithmic function; this means the crank stress load increases by nearly 90% - BEFORE adding in the differentials imposed by an increase in BMEP. By the time it's all done - the crank is being SPANKED with some serious loading! Spin it for the time involved to get back to back traps at Bonne', and you've got a prime recipe for crank dislocation.

    The beauty of using a blower is that the power output characteristic can be modified to do damned near anything you want it to - within the stuctural and architectural limitations of the motor. There can be a significant increase of the 'area under the curve' - this translates into a faster vehicle, even tho peak HP may not be significantly more.

    In the doodling I've done so far, a vintage S8 should be capable of intermittent 300+ HP/500 ft/lb power peaks AS LONG AS rotational speeds are held to 4000 RPM. Keeping the crank speed down reduces the stress on the crank - this limits the crank's tendency to 'whip' at speed.

    To manage this, the motor will require a computerized ignition system and quite possibly EFI. Fuel and timing maps will be critical; the motor will have to be 'tuned' to provide a flat torque curve throughout the RPM band. This is accomplished by pulling out timing advance as the revs build; doing so reduces peak pressures which contribute to crank failure.

    If it blows - so be it. It's been a while since I've really grenaded a motor - starting to feel like a conservative old fart! Worst I've done this year is to munch a trans, so dressing out a straight 8 only to have it spit out its bottom end on a dragstrip sounds like a helluva good way to spend one's free time!
     
  25. wannabewannabe
    Joined: Sep 1, 2005
    Posts: 259

    wannabewannabe
    Member

    It'd be a shame to lose another motor they ain't making anymore though... But I endorse your plan.

    Chuckspeed, you said earlier that a turbo is wrong for this motor, but in the same post you talked about diesels. Of course, that got me thinking: why not use a diesel-spec turbo on the ole Buick? Diesels don't turn anymore revs than the a S8.

    One consideration on these old motors is the manifold heat if you decide to run headers. The stock intakes don't have the provision for water heat like V-type engines do, so they used a thermostatically controlled flap in the exhaust manifold that warmed the intake while the engien was still cold to keep the gas from pooling (or condensing on those long intake runners). Without it, these old inlines don't run worth a shit when cold. It would probably be wise to fab up some provision for the heat like there is on Fenton headers for Chevy/Jimmy sixes if you plan to drive it on the street, i.e. not as a purely race motor.

    Also, the 320 motor was introduced in 36, so parts will interchange that far back. The 248, as you seem to know, was introduced in 37. From what I remember, according to California Bill's Chevrolet, GMC & Buick Speed Manual, the 248 will take up to a .125" overbore with sonic checking, and I think the 320 is supposed to be able to take .060" overbore. You can mill the shit out of the head, but with a motor like this (the old combustion chamber technology and slow revs) I'd keep the compression relatively low.

    The slantbacks are simply awesome. They're like baby Cadillac Aero-dynamics. As for working on them, a word to the wise: if I am not mistaken, the 37s still use some structural wood, whereas the 38s do not. They made a slantback century in 37 but not 38, Specials both years.

    Good luck with it all. I have impure thoughts about these cars and motors, too.
     
  26. wannabewannabe
    Joined: Sep 1, 2005
    Posts: 259

    wannabewannabe
    Member

    Oh yeah, I forgot.

    I don't know where you live, but Chuckspeed, in LA at the Petersen Museum, they have a small exhibit that is made to look like an old-timey speed shop. On the counter there (if they haven't moved it in the 3 years since I worked there, and given the way the place is run, they probably haven't, but I digress...) is 5 or 6 carb manifold for a straight 8 Bu. It's right out in the open where you can even touch it, so if you need some ideas... go take a look.
     
  27. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    I live in the Center of the Known Motoring Universe - Detroit. Of course, if GM decides to go tits-up, the COTKMU may relocate to Toyota North American HQ...

    Eww. That's a nasty thought. Scratch that.
     
  28. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    Your points are well taken, thanks!

    a turbo would work if:

    a) the turbo size was kept bitty.
    b) Fuel indjection and timing were used to retard the timing and enrich the mix to the point where there was post power-stroke combustion. This is a trick the turbo geeks use to eliminate turbo lag - along with a BOV to keep the turbo spooled between shifts.

    I dunno - feel like that you gan get to the same point with less plumbing and widgetry with a blower. Blowers are famous for down-low revs, and they do a GREAT job of overcoming intake tract/exhaust manifold inefficiencies. 6-8 PSI on an inefficient motor is good for a 40% power increase; my problem is I want more than that.

    As for the intake...

    Since the motor is essentially a torque monster to start with, it may be better to run short runners and allow engine heat to migrate back. If not, then I've had luck fabbing up water preheats on some of my other 'creations'; the advantage of a water preheat is that it can be thermostatically controlled - or completely shut off once the engine gets up to operating temp - thus optimizing power.

    Fuel injection would solve the issue on all counts, and by installing the injectors upside-down along with the rail...The motor could employ a couple of vintage carbies as throttle bodies while keeping the 'modern' stuff outta sight. Would be a trick setup.

    Been thinking about the bottom-end issues, and it may be that the bearing caps 'squidge' around like they did on early race FE blocks. When the bearing cap moved with the crank whip, it would allow the main cap bolts to loosen - the loosening of the cap bolts permitted more whip, and eventually the motor discharged its crank onto the track. The fix was to fab up billet caps and cross-bolt and jackscrew the cap to prevent the 'squidge'; betcha the motor would benefit from a bottom-end girdle and some crossbolting, if possible.

    As for blowin' up motors outta production...

    That's not slowed me down in the past. Back when I worked at the Henry Ford Museum, I'd get pissed off at the guys trailering in their vintage rides and cleaning out the dirt from the tire treads with a toothbrush. The engineers designed cars to be DRIVEN, dammit! Besides - Buick made about 2 million straight 8's over ten years of production. While they're not exactly layin' in the ditch plentiful - they aint exactly hen's teeth, either. A guy vintage racin' a chrysler 392 or a Hudson 7X is playin' with much more irreplaceable iron than the valve in head Buick 8.
     
  29. Broman
    Joined: Jan 31, 2002
    Posts: 1,487

    Broman
    Member
    from an Island




    It's about goddamned time someone else said something like that....I keep sounding like a fucking scratched record.



    You have WAY more know-how on what these motors need than I do, I have just been an advocate in the consecration of life beyond the evil SBC ;) . There is no excuse for tossing out a perfectly useable engine to make way for a SBC because it's "easier".......

    Thanks for getting my hair up again, it's been a long while since the Buick Brethren have united to advise another convert.

    I am pleased..... you amuse me, I accept your initiation request and dub thee an honorary member of the Secrect Society of the Brotherhood of Buick, the keepers of the torch and TIG. Anoint yourself with a dab of oil and a prick of the finger. You may stay.
     
  30. chuckspeed
    Joined: Sep 13, 2005
    Posts: 1,643

    chuckspeed
    Member

    I love you, man! I accept the initiation, and promise to provide an ongoing log of the antics soon to unfold in the House of Speed and Chrome.

    Thought about it last nite, and I think I'll do a mild version of the small 8 to start - something in the 185 - 205 HP range. You know - head work, compression bump, cam, header, exhaust, and some sorta induction setup which looks hot yet is driveable. I've promised the Peebmonster creature comforts, so some time has to go into engineering in power steering, power brakes, and an overdrive auto trans (ick!) whilst retaining stock appearances. After getting chassis dynamics sorted out along with all that hokey little stuff that takes for-freaking-ever, a big 8 will be sourced for a forced induction build.

    Question: will finned alloy GM drums from a later Buick/Olds fit the '37 spindles? I am NOT gonna go the modern shit under billet fat fender look; rather the car will have a circa '58-'62 'cruiser' feel to it. While a power booster under the floor is acceptable, discs ain't.
     

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