v6 buick motors

[old fella]

hi i am trying how to find out how to work the 3.8 litre Buick motor which was put into the Holden commodore in Australia, i was told that you can get 300-400 hp out of them naturally aspirated, i know that they used them in race cars any help would be appreciated.

[revolutionary]

What year range? old style or Series II 3800?

[stage1scott]

There is a TON of power in the cylinder heads, I believe Dart makes/made alumnum head s for them. Also intakes that will accomodate 2 or 4 bbl carbs, or use digital injection. The biggest downside to them is the oiling system-spend your money on that so you don't wind up with a pile of melted iron. I saw a couple of them kick the rods out on Ken Duttweilers dyno from time to time, he finally upgraded to an external oil pump, belt driven on the front of the engine, NASCAR style with an external pickup line inplace of the internal block passage. the #1&6 rods are the last place to get oil, after the cam/lifters/top end, so oil level and volume are critical to avoid starving those rods.

[CTX-SLPR]

The majority of the Aussie 3.8's are the 3800 Series I, II, and III variety though the pre-series stuff did make it's way down there. I don't know so much about what's available down there and N/A versions but they are stoutly built motors from the factory and the Aussies were lucky to get them in RWD instead of just the 95-02 F-body like here. Look up L36 modifications and that should get you started if what you have is what I'm thinking.

[SpiderGearsMan]

I think the busch motors may have had 450 hp , the cranks would not last more than one race

[old fella]

it is the series 2 motor, i new they had crank issue after 6500 rpm but didn't no about oil prolbems, i want to put it into my boys dirt speedway car which ways 1.1 ton race weight, quater mile circle sort of, car running electrcial injection on methol with a mircotech computer, with extrausters, doing around 5500 to6200 rpm running top gear 1.1 with a 5.78 diff ratio,need torque to come on around 2500 through to 6500 rpm.i also heard they have to flow injection ports 5 and 6 because of the sharp radius into heads, any ideas?

[realsteelfreak]

Cam bearings is the weak link in the oil presure on the Buick V6.
Nascar engines was based off of the 4.3 Buick V6 at 262ci with bore and stroke increases and those parts were available in different stages eg(1, 2 ,or 3)(heads ,block,crank(really just bare castings needing finished) got wilder depending on he stage.

[SpiderGearsMan]

cam bearings on the pre 3800 for sure
galling ft covers oil pump
the fixed it with a rotary oil pump

[CTX-SLPR]

Cam bearings is the weak link in the oil pressure on the Buick V6.
Nascar engines was based off of the 4.3 Buick V6 at 262ci with bore and stroke increases and those parts were available in different stages eg(1, 2 ,or 3)(heads ,block,crank(really just bare castings needing finished) got wilder depending on he stage.

The only Stage 3 was an experimental 4-bolt main 455, not a V6. There were Stage I's (Big Blocks had Arabic numerals, V6's had Roman) which were the early racing pieces then the Stage II came out which had different heads, 14 head bolts, available in On and Off center varieties, and could be bored to 4.020. There was never a 4.3L Buick V6, there was a 4.1L V6 with a 3.965in bore and there were lots of different strokes you could get to go from 3.5-4.7L using a Stage II dry sump block to get the oil pickup gallery out of way of the stroke. Stage II heads came in 3 different varieties that I know of, Big Port Busch, Tall Port Indy, and Square Port Indy. They were all symmetric (I-E I-E I-E) vs the production pieces which were clustered like an SBC so they took specific cams. The cam bearings on the stock stuff are a weakness because of the oiling restrictions but the Stage II had drastically improved oiling.

Finally back on task, a Series II/III block in a cross bolted main, short deck, on center version of the classic 3.8L Buick V6 with a gerotor oil pump to replace the spur gear unit and a balance shaft. People have made 400hp on them NA by upping the compression, porting the heads, and running some insane rocker ratios (a lot of which are imported from Australia, Yellow Terra). Intense Performance and ZZP are the ones that were pushing the technology when I was into Series II motors. I've never heard anything about the rear 2 cylinders needing more injector because of the heads. Intake yes because on the classic 3.8L LC2 Turbo6 the plenum would cause air to pile up in the rear and make those cylinders run lean and need more fuel. I also know nothing about a Microtek computer either.

[SpiderGearsMan]

if you have enough cam - leave the rockers alone .......