Vitamin B455 with a bit of TBI fortification

Howdy,

Call me crazy and bored at work but here's the idea. A Buick 455 (Vitamin B455) has a firing order of 1-8-4-3-6-5-7-2, same as a BBC, HEI distributor bodies are identical but not the shafts and gears, The Chevy 454 had TBI with a computer controlled HEI for many years. Why could you not take a factory TBI setup with computer, harness, throttle body, and distributor and then stuff the same stuff into a B455 distributor and use an adapter to put the thottle body onto a B4B or performer and have full factory reliable, computer controlled (OBDII if you wanted), Fuel injected fun without really messing with much?

Just some ideas,

 

I like the idea, any ideas on good donor cars/trucks?

 

Interesting idea. However, and I'm sure someone will correct me if I'm wrong, but don't Chevy and Buick distributors rotate in opposite directions?

 

no actual parts involved, its all in my head, for some reason I keep thinking budget beater since its taking so long for my high power, high tech project to get done. I'd just look for any old BBC truck and grab the computer, harness, Throttle body, and probably the transmission, heck my friend wants a BBC so I'd grab the whole drive train then sell him the block minus the stuff I wanted then pick up a salvage yard Vitamin B455 and then find something to put it in. Probably have to have a custom chip burned but that's not bad. As for the distributor.... no idea if they are reversed in rotation. I think you could use an MSD Pro Billet anyway and bypass the stuffing.

Don't get mad, get informed,

 

You can put the module from a TBI ignition in a HEI, you have to cut the housing and cap a little but no biggie, just seal it with silicone

 

tbi sucks

if the state of california would let me i would remove the tbi from my 454 suburban and install a q-jet!! i know i could make it run better and more efficiently than i does with the tbi. that system is junk from the start imho.

 

It ain't for power. Drivability and engine longevity are it's only benefits. They really stink on the 454's. The computers are crude too. you are better off building a port injection manifold and buying a megasquirt. It can all be done with junkyard parts and the megaswuirt will cost about what the dyno time would if you wanted a custom chip burnt for your mix-match of parts.

IMHO, of course

 

I'd like to see how to build a junkyard port injection manifold.... I'd agree that a TBI system is far from the ideal setup but considering it should run with the intial 454 tune on the computer I wouldn't think it would take too long or much doing for someone to custom make a chip, especially with virtually all the original equipment still inplace just on a different engine. Another thing is that I hate Speed density EFI systems if the megasquirt is really even a speed density not an N-Alpha. Besides this is more of a driver oriented project, not a speed demon. I'm thinking 4dr 61 Lesabre or wagon with a TBI 455 in the nose with a 4L80E transmission, should be a fun family cruiser. I've heard a rumor that 76 heads are closed chamber? Are they?

Don't get mad, get informed,

 

I'm with you, I'd love to get a cheap EFI on my driver.

I believe that the '76 heads have open chambers, earlier years are closed.

 

Hmmm.... I wonder what year of stock heads have the best chamber design? I'm not particulary worried about best port flow or anything, more along the lines of effeciency. A 9.0:1 iron headed 455 with some headers and a performer/B4B should be able to run happily on 89octane. I know of some decent 61 4drs around here but I'd really like a 61 wagon, you almost never see those.

 

Pretty sure the '70-'75 chambers are all the same design/shape, just different volumes, with the '70's being the smallest / highest compression. From what I've gathered here, any of them would do, the thing to shoot for is a good tight "quench area" between the piston and chamber, like .030" - .035", for the best combustion efficiency. You set the "quench" by decking the block and/or milling the heads.

 

Exactly the old school inverted dome pistons that Buick's use are horrible for that though, there isn't enough flat surface to really squish. I had custom ones made for my 4.1 V6 but at about $500 for a set of 6, I'd be blowing the budget part of the build. I'd think I'd want to run the shallowest dome pistons with the largest chamber of the '67-'75 heads with stage valves and compromise the cam for enough overlap to keep from knocking and pinging at low engine speeds, high loads on mid grade gas. I wonder if the TA heads are drastically better in the chamber department?

 

I thought there were flat-top pistons available in forged?

 

From what I've heard, even with 76 heads the true flatops still yield about 11.5:1 compression, I'll have to check TA about that

 

Talk to anybody that burns custom chips for a living. I think they will tell you that you'll never get it right without a full chassis dyno tune-up. don't take my word for it, call one of them and ask.

I think that TBI would be considered a speed density as it has no direct air-flow measurement capability. Wouldn't it?

I'm not against your way of thinking, I just want to see you succeed for the lowest $ possible.

The best chambers are the 67-70 with the 71-72 being close behind. The 75-76 are considered horrible with lots of volume and little/no quench. The stock dished pistons aren't that bad as there is a little bit of quench all around the outside of the piston when used with the earlier heads. The short ignition lead requirement of most Buicks proves that the CC design is a pretty good one (excepting the 75-76 heads).

Flat-tops are available if you want 12:1 compression or so.

 

Hi Guys,

'75-'76 heads ARE horrible and the MOST detonation producing BBB heads Buick ever produced....stay away from using them at ALL costs. Quench (squish) is a MAJOR key to detonation resistance...the tighter the better!:TU:

The '67-'69 Big Port 400/430 heads will get you the most flow without porting (if that's your goal for lack of porting funds) because the ports are actually cast bigger than later years BUT that makes them thinner in many areas so I would NOT port on them unless you have access to a sonic checker and know what you are doing. THEN the '70-'71 are the best if you plan on porting. '72-'74 are a VERY close second behind the '70-'71.

My personal opinion (further backed-up lately by the Jeg's Engine Master's Challenge) is as small of a combustion chamber as physically possible with as much volume in the piston dish as needed to achieve the desired compression ratio. Then with as tight of quench as you can get without any chance of the piston smacking the head deck at RPM.:TU: The quench area you SHOULD shoot for is .035"-.045"..., .035" being IDEAL for a street driven vehicle.

Hope this helps...

 

MPFI is what you want.

 

PRECISELY!:TU:

 

Well I did call turbocity and they said they have done a few so I trust them to get it close to right on the first try. However if I wanted to max it out I would have to dyno tune it because every engine is different and they have to protect thier liability by offering chips that run well but not extremely well sight unseen on a variety of different configurations.
Oh I am a believer in Multi Point Injection but the problem there is that you need a manifold that is setup for the individtual injectors and thats not such an easy thing to come by. Then you get into what kind of computer to run it aswell, and as I mentioned earlier I hate Speed Density and pretty much have decided to run a Mass Airflow system if I'm going to run an Multi Point Injection setup. The throttle body set up is pretty much just an electrically controled carb that sprays fuel into the intake stream instead of has it sucked into it so it functions much the same way as a carb but has superiour ability to compensate for engine coolant temp, engine load, cold start... that kind of thing. With this in mind I don't mind using a Speed density since the percision of the system is not nearly as high as an Multi Point Injection with sequental or batch fire, its just 2 or 4 injector duty cycles to adjust in bulk since the manifold is wet flow.
Will any subtly modified B455 run on 87 or 89 octane or is premium required for all of them? Right now this is rather dreamish but if it gets sorted out well enough and the part pop up, I might have to put my turbo6 65 Riv on hold and do some budget cruising.

Thanks,

 

To reliably run on 89 octane (I wouldn't feel real comfortable with 87 but it CAN be done)....factor in what I've described above then add in the intake closing point of the cam. This will determine your dynamic compression ratio...shoot for around 7.5 to 8.0 for this application.:TU:

IF this is for a turbo-charged application THEN absolute cooling of the intake charge is VITAL (cooler intake charge is good for ANY application actually!). Use as BIG of an intercooler as you can phyically fit in your car's given space....it WILL pay MAJOR dividends!:TU: Also the use of an alcohol/water injection unit will help too.:TU:

Hope this helps...