Barry's thoughts on performance.

[BarryGMC]

Over the years I have had many discussions about sizing carbs and exhaust for the application the engine is being built for. Not just for the v6 but for all engines. I routinely pop out 550 hp 454s that run Holley 650 carbs and single 3 inch exhaust. These motors will burn the tires off a one ton dually all day long. Now I have concluded through trial and error that the 305 is best set up with a stormberg or Rochester carb and a single 2-1/2 exhaust. Even with a milled head and an 8.5 compression ratio. Volumetric efficiency is good and peak torque is achieved down low in the rpm's. Now it gets fun. It's really easy to get the 305 to put out 250-270 hp and 400 lbs of torque. Here is the heart of it. Let's see if some one knows what it is.and what it came from. Later we will discuss more of the details. Barry

[1969_CM2590D]

I bet it uses Turbo Rocket Fluid!

[BarryGMC]

Funny Dennis . I have been reluctant to share this. First the parts are rare and I really think the v6 runs well as is. But it have really pulled some hp out of these old guys. And after getting ripped by the ignorant I feel ready to dissect and discuss the potential of the small v6 engines. Barry

[1969_CM2590D]

It's really pure coincidence I came up with that, Barry. A little while ago, I put the post on here about a V-6 in a Jimmy. Well, I decided that motor would go better in a 3/4 ton Suburban, since they weigh about 800 lbs and up. So, i looked around for something smaller from GM (except Chevy) for the 104" WB Jimmy. I have the Pontiac OHC 6 at the top of the list. But then the Buick 215 aluminum V-8 came to mind. So needless to say I ran into the Olds Jetfire motor. Olds to0k a different tack than most with it as they used it on a high compression engine as opposed to a low one. It's a rare bird as most people forgot the Rocket Fluid and burned up the turbo motor, replacing it with a standard 4bbl. Obviously spares evaporated a long time ago. The Rocket Fluid was an alcohol/water mix, but it's said water alone works well. It's not a new idea, water (and methanol) injected turbos were used in WW II planes. I tossed the Buick /Rover V-8 for a Jimmy project though. Even though it was used in Land Rovers and eventually enlarged to 5 liters, the steel cylinder liners have been separating, so i wonder about durability.

I wonder if that would bolt up to a OHC 6 Sprint manifold, hmmm...

You are, of course, right. There are many intelligent/not so obvious ways to get HP and torque- with efficiency. I've got a couple of books here to study on that. Someday, I'd like to build a Locost BMC A-series that would burn the Porsche pilots.

You really scavenge! Maybe I can meet you at my favorite junkyard if you're on this side of the world sometime...

[BarryGMC]

It's funny you bring up the 215 buick. In 1960 gm came up with the big v6, the flat 6 corvair and the 215. I have used the 215 and love it. It's getting hard to find in its original form though . Best small jeep motor ever in my opinion. Buick bell with a 420 trans and spicer 18 and a warn overdrive with 4.88 gears. Love it. The little set up in the pic is crazy up to 5 litre really. A 3 to 4 litre up to 6000 grand it will pull your hair back. 4 to 5 litre max 5000. You would crap at the stuff I have collected. Not to brag if it's old and cool I probably have it. Barry.

[BarryGMC]

Hey Dennis we have better old stuff here. It's common to still see 60-70's rigs here as daily drivers. PS when someone tells me what this came off of we will talk about its application on the 305 v6. Barry.

[turbobill]

I have a complete 215 Jetfire engine. Fortunately it had a 4 speed so I can bolt most any other GM manual behind it.

The turbo set up is very similar to what Buick used on their later turbo V6's starting in 1978. The one you picture looks like the early Buick setup used on the carbureted 231's. I have about a half dozen of them floating around here, plus one Pontiac 301 turbosystem.

If I ever get the time, I'm going to single turbocharge both my 478 and one of my 305's. The turbo on my 468 Chevy will be used on the 478 and for the 305, I'm going to experiment with both the 231 and 301 turbo's. The 231 turbo should spool way down low and compliment the low RPM torque peak of the 305.

[BarryGMC]

I thought you might be the one to recognize it. I did one on a v 6 and it fit so nice that I could convince people it was stock. I plan on doing it again and look forward to your thoughts. Barry

[Larry]

Turbo buick/grand national clones