Hey Yall, I just finally bought one of my bucket list cars, a 1952 Buick Special 4 Door and I’m looking for some ideas for the engine bay and mild power gains. I’ve been doing some looking around on the forum but I haven’t seen anything recent on the topic. Here’s what I’m kicking around: multiple carburetors (4 DCOE Webber’s or 2x6 9super7’s), larger valves (maybe the Buick 401 V8 valves?), porting the intake and exhaust runners in the head, some sort of unique exhaust (matched length, 180 degree, front half of head/ back half of head), ect. What do yall think? What have you done?
Here's some info on the factory installed dual carb setup used on the earlier Buick straight 8s. You'll need to do a bit of research on interchangeability due to the shorter and longer blocks Buick used. https://www.jalopyjournal.com/forum/threads/straight-eight-multi-carb-intakes.61803/
I haven't done it but here's some reading: https://www.teambuick.com/reference/i8_speed-secrets.php https://californiabills.com/p-10-chevrolet-gmc-buick-speed-manual.aspx https://www.jalopyjournal.com/forum/threads/straight-eight-buick-motors.154779/
If the intakes will interchange (check the part numbers on the intake manifold to cylinder head gasket), then as mentioned earlier in the thread, a factory 2x2 intake, with slightly larger internal venturi than factory, Carter or Stromberg carburetors. Carburetors should be exactly identical. Run the carbs with straight linkage, not progressive. Your car, and your engine. But you couldn't offer enough for me to attempt to set up 4 webers, even if you can fabricate an intake, and especially not the 9super7's. Another option ONLY if either (1) cost is absolutely no object, or (2) you have excellent metal-working and fabrication skills, would be to fabricate 4 individual 2-barrel intakes, and run them as IR. Use four period matching Buick 2-barrels (either Carter or Stromberg). Do not interconnect the intakes. In a different lifetime, when I was still restoring carburetors, have set up a number of the 2x2 set-ups using period Stromberg and Carter carburetors, when the customer supplied the intake manifold. All of these customers were happy with the results. Have only done one of the 4 two-barrel with the IR design, but again, happy customer. In the same lifetime, sponsered a four cylinder circle track racer. The "hot set-up" was supposed to be a Weber whose specifications now ellude my memory (one tends to forget bad experiences when possible), but I believe it was a 48 IDA. After spending over $1500. in the original purchase of the carburetor, and venturii and jets of multiple sizes, and way too much time, neither myself, nor the then Missouri resident Weber expert could make it run as well as a $5.00 junkyard Autolite 2100 that I simply threw a kit in, and ran with the stock configuration. If you are searching for reading material on the internet, Buick called their dual two-barrel set-up "compound carburetion". Sounds like a fun project. Jon
The Buick 2 carb manifolds were stock in '41 and '42. Super and Special manifolds are the same, Roadmaster is longer. Only one carb had a choke. They came with "special" exhaust manifolds. As for larger valves I don't know if 401 valves have the same diameter and length as the st 8 If the car has a Dynaflow you have to get rid of that.
^^^^ The 2 carb intake and exhaust manifold setup would be a good mild performance gain, but that is a hard find. Other tricks include a little milling off the head and polishing the exhaust ports. There is not much meat in the intake ports, and aggressive porting may hit water. More intensive modifications such as re-grinding the camshaft may get a little more performance.
Getting some compression is the main thing. I bored mine 120 or so over and aftermarket pistons. Sized for 9.5/1. Had a performance shop do the head. I don't know what valves were used. "Little bit " of cam. OT fuel system. I am happy. Ben
Could you clarify the term IR for me? That’s definitely exactly the kind info I’m after for carburetor and fuel system stuff, thank you. I’m curious why you wouldn’t touch the webers or the 9super7’s? I was thinking for the side draft webers building that same style 2 into 1 intake runner that you were saying for the factory style carbs but instead of down draft OE style carbs, running the Webers in much the same configuration I can’t imagine it would be a whole lot different as you would only be tuning 2 cylinders per carb, please correct me if I’m wrong. As for the 2x6 9super7’s that I was thinking of building in a “log” type configuration and setting it up as secondaries at 1346 and primaries at 2&5 for what would hopefully be the best fuel distribution in that situation. Only thing with that set up will be figuring out the progressive linkage for running the manual secondaries. I forgot to mention I’m also planning on running a 700r4 with this engine no matter what (because it’s what I already had sitting around)
You do know that a 700R4 will require a different rear end and complete redo of the rear suspension, correct?
IR is short for "individual runner". There would be no interconnection of the four carburetors. For carburetion purposes only, this would separate the engine into four two-cylinder engines. The air flow requirements of two-cylinder engines is different than from four-cylinder or greater than four-cylinder engines. I was not knocking the Weber carburetor in my previous post. What I was trying to explain is that, while the Webers are infinately tunable; many parts (all expensive, and not readily available in the USA), plus equipment and individuals with knowledge of the Webers is required. I spent $1500. about 30 years ago trying to make what was supposed to be the hot set-up work as well as a $5. junkyard carb, and could not. And I will confess that I am NOT an expert on Webers; but the "local" Weber expert could do little better than I and not close to the junkyard carb. No comment on the 9super7 units; I am reasonably sure others will comment on these. For the record, I rebuilt my first carburetor in 1959. And while this is a hot-rod forum, and while any true hot-rodder can make a Holley Dominator work on a Sears lawn-mower (just ask them ), my experience since 1959 is that starting with something calibrated for the same or a similar engine saves money, time, and frustration! This is the reason for suggesting original Buick Stromberg (AAV series, or even later WW series) or original Buick Carter (WCD series or the later WGD) series. All of these are close to being as tunable as the Weber (the Carters possibly more so) plus parts and many folks with knowledge of these exist in the USA. As an example on parts, the Carters can use genuine Carter AFB low step jets, which are readily available, and cheap. As I mentioned in my first post, it is your car, and you make the decisions. I feel that going with the Webers would add a LOT of complexity, not to mention expense, and probable frustration to your project. Which ever way you go, have fun. Jon
Yes, I’m going to 4 link it and give myself the option of airbags or coilovers I have a chevelle 10bolt for the rear
Awesome was just looking for more information, things I wasn’t thinking about. I greatly respect that a lot of guys will have been at this longer than I have and that’s why I am asking questions, asking these kinds of questions also happens to help me at work so it’s a win win I did some research on the 9super7’s….. yeah if that’s the way I go, it will be real deal $tromberg. I hadn’t thought about the accessibility of parts and ect. when I was looking into the Webers. Using the Carters or the Stromberg that would have been on the car or available in the 50’s can I still do something similar to the 2x6 configuration?
Going to a 700R4 will require a custom adapter and crank spacer/for the flexplate. I would research what may need to be done to offset some of the "harmonics" inherent in that long crankshaft. Having the crank ***embly balanced with the spacer and flexplate installed may be in order. Those issues were one of the reasons I did not go the I-8 route.
I know a little about too many things but I will add, from Jaguar experience, Webers I have played with tend to need RPMs, and run in a narrow range. You will not get the torque for the bottom RPM range of the Buick, and the Buick can't run in the higher RPMs of the Webers.
Does it really need to be balanced? There’s a few different options for an adapter to go from the dynaflow to a GM TH auto trans
^^^^ Balancing the ***embly may be necessary, depending on the adapter used and how it is manufactured. I know the early Nailhead adapters come balanced for the application, but I never researched the straight 8 ones. I abandoned the 248s in my cars early on as there were too many hurdles. Going a 401/ ST400 combo in one, and a 292 Chevy 6/700R4 in the other.
I'd get all the transmission and suspension stuff worked out before starting on the motor. Then pull the head and o-ring the block. Larger valves if you want and mild porting. Probably a new timing chain. Leave the rest of the engine alone if its in good running condition. Then put a small turbocharger on it. Not huge pipes and stuff, just a small neat package like they used on 62 Olds Cutl*** or a Corvair and then an intake manifold that suits you. You don't have to get inside the engine and a stock cam may be just fine. Lots of room next to that inline 8. Good idle and good power when you want it. Bound to generate attention.
From my old Buick hunting days, wish I had more info for you but might sparks some ideas? Checked last year and unfortunately he sold all he had and donated one set-up to a museum he said.
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