305ci V8 vs. 292ci I6...just curious.

I may be wrong, but I don't think it does weigh less.

Reply to
Joe Smith
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Any bolt on for a 230 or 250 will work. Not 235 or 261 part. Also the

292 is not light in weight and likely weighs about the same as a 350 but is a lot easier to work on and very excellant low RPM responce.

----------------- TheSnoMan.com

Reply to
SnoMan

I wish I had the blueprints on it... It was a while back...

Reply to
Shades

Well right now I'm just trying to get a general estimate on cost of building one up. Of course, getting it in the truck will be another matter, but shouldn't be ridiculous seeing as how that engine was offered in that truck.

I'm looking into cams, and I'm thinking of going with something with short duration and little overlap to get a good idle with low-end torque. Plus if I were to super/turbo charge anything, that cam would be a good choice far as I can tell. If I plan on doing that, I'll go ahead and plan on having around an 8:1 compression ratio.

Know of any good sites that detail the specs on the I-6's? Like bore, stroke, compression, etc...?

~jp

SnoMan wrote:

Reply to
Jon R. Pickens

Not to rain on your parade but a 350 will out pull a 292 six. And if you were to start hopping up the six it will cost more per HP gained than a V8. If you want a lot of low end grunt build a mild 383, 350 with a 400 crank, or find a stock 400. No matter what anyone here tells you, you will be miles ahead. There are lots of low buck 383 rotating assembles around. Lots of early big Chevy's have 400's, and they were in pickups till 79.

No one mentioned this before but the 305 is anemic as produced. They, like most small blocks, come alive with a tiny bit of work. Cam, intake and headers will wake it up. It would cost a hell of a lot to get the same performance out of a 292. Change the pistons and heads and it will really wake up. Now you're in exotic territory for a 292:)

Al

Reply to
Big Al

Well...it's not about what will out-pull what... A Duramax would out-pull the 350, but I'm not going to install one.

Since this is now my fun truck, and not my daily truck, I'm approaching it differently than I would've in the past. I will be upgrading some parts along the way, like axles for instance, but it's not going to be an offroad beast with 12" of lift, and it's not going to be a towing vehicle either. It'll probably get a few inches of lift and 33" or 35" tires max, and I plan on 86-ing the fiberglass top in lieu of a soft top for cruising up into the mountains on nice days. If I can find a dirt trail to get into, all the better, but I'm not interested in competitive off-roading or pulling super-heavy loads, nor the power levels required to do it.

Not to mention, I like "different". K5's with 350's and 383's are all too common. Then you have the big-block crowd. I prefer to stand out in the crowd a bit. If you knew me personally, you wouldn't be surprised at all, LOL...

And for the record, my 350 won't out-pull anything. Yes, that could be changed by swapping the cam, but I'm over it. I say bring on the 6. :-)

~jp

Big Al wrote:

Reply to
Jon R. Pickens

Not to rain on yours but a 350 is no match for a 292 below 2000 RPM or so and with a stick is would be a real stump puller with nearly full torque availble right off a idle. It has low RPM torque that will even rival some old diesels because you can pull it at 1000 RPM and it will do so strongly and smoothly. You would need a 400 small block or big block to match this low RPM torque and a lot more fuel too. Myself I would be tempted to build one up with 12 to 1 CR or so and run it on propane as it would make great power, get about the same MPG as gas on

8 to 1 and there would be no carb to flood out or starve out in any position off road. On top of all of this it would be basically a zero emission vehicle too. Propane has a octane of 110 plus and while you have to have a heavier tak to store it, it weighs less than gas (4lb vs 6.5) which offsets tank weight and it energy density per lb of fuel is actually a bit higher than gas too. (about 10% more). If you realy want to get wild, GM made some truck V6 from mid 60's thru early 70's in 305, 351, 401 and 478. THey all shared same block. THe 305 was used in GMC pickups through about 70 and the 351 was used in a few too. These were real stump pullers too. THe 401 and 478 was used in HD trucks and the 478 saw a lot of use in HD drumptrucks during that time and was a force to be reconned with as it made almost 450 ftlbs of torque at 1400 RPM in stock form. Check out link below and check out the 637 V8 and 702 V12 GM had.

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TheSnoMan.com

Reply to
SnoMan

...'cuz we all nuthin' but a bunch of idjuts and you iz the only smart one...

Reply to
Shades

I've considered the propane thing at times myself. It would be interesting if I were able to plan fuel stops ahead of time.

Concerning RPM and torque... you're basically describing exactly what I'm looking for. At 80mph in OD, with 3.73 gears, I was right at

2000rpm. I don't need an engine that peaks above that, so again, it sound like the six is what I need.

~jp

SnoMan wrote:

Reply to
Jon R. Pickens

Sometimes I think you're smart, other times you astound me. You are ALWAYS preaching low rear end gears, now you're an advocate for lots of low end torque. Make up your mind:) Now how much money do you have to bet on what you just wrote? At 1999 RPM (That's under 2,000 right?) I have a thousand dollars that says a completely stock 350 will out pull a 292. How about it?

Al

Reply to
Big Al

I wish I had $1000 to bet...I would DEFINATLY put it on the I-6!

Reply to
Shades

In a offroad machine you need good low RPM responce so that you do not have to wind it up to pull smoothly idling or have to slip the clutch a lot in a taller gear to keep engine from racing otherwise. What works towing and offroad is not that far apart in that you need to match your power curve to the load at hand. Most V8's (especailly small blocks that are setup for midrange and top end power do their best above 3000 RPM pulling hard while sixes are quite happy at 2000 RPM or less and were designed that way. Also you find me a stock 60 era 292 with a stick and a 350 with a stick and pull them at less than

2000 RPM and the 292 will smoke the 350, especailly at 1500 RPM and less. With automatic the results would be different depending on stall speed of converter but at low RPM the old 292 is awesome. I know I drove some of them when they were in their prime and they were is a leauge of their own at low RPM's with a stick. I would be taking your money.

----------------- TheSnoMan.com

Reply to
SnoMan

One weight reduction, aint going to happen with fiberglass panels stout enough to handle being an everyday driver.

The Chevy 250 long block weighs 440 pounds, I would estimate another 50 pounds for the 292 because of the taller block, and a beefier crank,

The small blocks with cast manifolds (intake and exhaust) weigh 575 pounds.

Of course if you really really want something different, find a Jimmie 478 cid V-6 for it.

235 hp at 3,200 rpm, 440 ft/lb of torque at 1,400 rpm, and a "round" flywheel housing bolt pattern for use with truck trannies, like allisons. then there was the 351 cid V-6 that one 180 hp at 3,400 and 312 ft/lb torque at 1,800 to 2,200 rpm. Course you could go way off the deep end and try and find one of the Jimmie V-12s, which were basically two V-6s, and back in the early 60's they out pulled almost any diesel rig on the road
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is good page on these beasts. As for performance parts, there is only one place, CliffordPerformance.net. They wrote the book on 6=8.. 4 bbl manifolds, fuel injection, side draft webers, what's you choice? They build the best headers, damn things don't crack, don't warp and don't leak. They have cams, as well as blue printed heads. Old man Clifford tore the race tracks up with Hudsons, everyone for the them an L-6.

Whitelightning

Reply to
Whitelightning

why hasn't anyone suggested a 455 if you want to be different. I had

70 442 that would smoke the tires at 60 mph just by dropping to third and nailing it. hell put a 4cylinder cummins in it
Reply to
dave

Eh... a big block would be overkill for my application. I still want to be able to drive it on the street and not have to save up money for my weekend in the truck...LOL.

There's enough big-block'd Chevy trucks on the road.

~jp

dave wrote:

Reply to
Jon R. Pickens

Not that different...I have seen more than a few 455 Olds and Buicks in Trucks and SUV's.

Reply to
Shades

Oh yeah... the Cummins 4BT was something I considered for about 5 minutes. While it would be cool, that may require a bit more fabrication than I am ready to deal with.

But it *is* a cool idea...

~jp

dave wrote:

Reply to
Jon R. Pickens

Well said, thanks.

Al

Reply to
Big Al

Is the low-end "torquey-ness" of the 292 attained by the long stroke?? (more leverage against the crank?)

I found the specs on Chuck's Chevy Truck Pages and noticed that the stroke is 4.12" whereas the 454 has a 4" stroke, follow by 3.75" for the 400 SBC, and everything else is roughly close to 3.5". I can see where that would make a huge difference.

~jp

SnoMan wrote:

Reply to
Jon R. Pickens

The longer the stroke the more torque you can make with a given bore size. Think about a wrench, the longer the wrench is the more torque you can apply with the same amount of force on the wrench.

Tractor engines are another proof of concept item about longer throws creating torque. The other trade off is that the longer the stroke the lower the rpm ceiling is for an engine. Cargo ship engines create huge torque but they turn 250-500 rpm max. They also have strokes measured in feet...

Reply to
Steve W.

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