The Stovebolt Site Forums The Shop Area Engine Shop low end torque and perferformance??????

I finally located a newer 6 to put in my 62'. Now I will be able to add a Turbo 350. My question is this, will I lose or gain power and torque by adding headers? Or better yet, will I see enough of a gain to warrent the time and effort?
My truck currently has a 62'261 and I'm relacing it with a 73 250 with HEI,(non intergral head).

Get the headers. The stock intake/exhaust manifold set-up is a drag.

6T2, check your email, I have another 250 for you if you want to trade for your 261, any shape.

Whether or not you gain torque and power thru headers depends, I believe, on how you finish out the system. What I mean is that, from my limited understanding of exhaust systems, the size of the terminal pipes will directly affect torque and performance. According to Leo Santucci, an expert on later Chevy inline 6s, it is better to err in favor of smaller rather than larger exhaust pipes ("Chevy Inline Six Power Manual"). I was just reading this section this morning.

So headers, properly installed and configured, on an inline six cylinder Chevy engine will give you greater power and an increase in low end torque, depending on your cam choice. I plan on running 1 3/4" duals w/Flowmasters behind my .060 over 292.

-ftyler

Here's another question. What difference is there between a 261 and a 250? Performance wise, not displacement. Since I will be able to add a turbo 350 to the later model motor. Won't that compensate for the small decrease in cubic inches? Keep in mind that it does have HEI and will have headers. Maybe I'll add 3 carbs, since I have an intake

The 261 is, physically, much larger and MUCH heavier than the 250. The cylinder walls are thicker the stroke is longer. It's essentially a larger bore 235. Obviously it has 11 more cubic inches.

The 250 is physically smaller and lighter than the 261. But it has several advantages over the larger engine. A 7 main bearing design makes the bottom end more robust when balanced. This plus the shorter stroke allows the 250 to safely turn more rpms. And with the newer v8 style bellhousing the tranny possibilities are tremendous.

The 261 probably has more torque factory stock than the 250, but the 250 can be built cheaper for high performance than the 261, and probably outperform it. Another tremendous advantage for the 250 is that replacement parts are readily available at most any corner auto parts store.

If you can find one cheaply you might want to consider the 292. The 261 has absolutely no advantages over the 292 - none. Unless you consider larger and more weight an advantage!

Be good!
-ftyler

Stick with the 250. It takes less work to get more power out of the 250. Many parts are interchangeable with the SBC. Valve train is far better. Ever try to get non-cast rockers for a 261? My friend tried and finally gave up. The 250 is a better engine using 60's technology versus the 261 use WWII era technology. Chevy had a hard time justifying changes to improve their line of sixes in the 50's, one of their major downfalls.

Now, if you want a real engine, follow tylers lead and go with the 292.

Hey Fred T,
I'm in the process of tearing down a 61' 235 thinking I was going to get away with minor overhaul, but starting to think about a complete replacement. Where do you find a 250,261 or 292 and how much should you expect to pay?

ukonjac you're relatively close to me (NC vs GA) and here 250s are a dime a dozen. I've had one offered to me (integral head, turned it down because I don't have the room). Average price of a complete 250 without the integral head can range from $75-$150 if you remove from vehicle. Individuals will often sell them for less when they swap out for the SBC - the 250 gets in their way.

The 292 is a different story. I see about one 292 for every 20 250s in salvage yards. I've seen prices from $150-$275. They've become pretty popular with racers wanting to be different and the price reflects the demand. A good running 292 will usually ALWAYS set you back $250+ in western Georgia. I paid $150 for a 292 short block that I eventually used as a core.

I'm almost finished with my 292. I have everything needed to start putting the engine together. First I need to slap on a nice coat of paint. I bought Chevy blue and have painted the timing cover and side covers. But now it looks more boring than the gray that it was painted when I received it.

I'm considering Chevy red or a gray that is close in color to what the short block currently is. Can't make up my mind. :mad:

-ftyler

I'm not sure about the 261s and if a 261, 216 or 235 wasn't stock equipment in your vehicle I'd forget about it.

Well blue is not as sexy as red, just depends what your own preference is, but grey reminds me of an old Detroit marine engine. Thanks for your advice but that leads to some other questions if you don't mind suffering my ignorance a little longer.
1. How long/what models or applications did Chevy make the 292.
2. How will that match up if at all with my 3 speed transmission/rear end, radiator(already reconditioned), engine mounts,etc. I guess I'm thinking I could scrap the 235 and get something within my budget to replace it but worry that it may cost me a lot more than the $250 price of an engine when you add in the expense of the conversion parts/accessories
3. Will steering and front axle suspension be affected. I wouldn't think so but I've never been involved in modifying the power train/plant before
4. Is there a source for locating used engines? Are there any overhauls available at a reasonable price?

Guess that should do it for now, huh. Again thanks for your comments.

Unfortunately, dude, I can only answer #1 and part of #2.

The 292 was widely used from 1963 to (I think) 1989 or 1990 in Chevrolet trucks. Applications were 1/2 ton & up trucks. In the 60s through early 70s, Chevrolet used the 292 in their C10-C60 series trucks. The C50 & C60 were huge vehicles that had 2 ton + payloads. You can still find some big 292 powered rigs on the roads today. I often see them used as logging trucks or heavy equipment haulers.

It sometimes is strange to open the hood of huge dump truck in a salvage yard and see a tiny 292 bolted in. Seems like it's not enough engine for the rig but obviously it was.

(answer to #2) How the 292 mates to your 3 speed depends on the type of 3 speed. I get the feeling that it's one of the pre-62 3 speeds made to mount behind the 235/261. In that case it won't work with the 292. I think there may be an adapter made for such a conversion but it wouldn't be worth the money. The 292 can bolt up stock behind a wide series of overdrive transmissions as well as the TH350 and Th400. These are versatile engines.

But if power is your goal, or most power for the $$$, then if you're willing to go through the trouble for mounting the 250 or 292, then I'd go with the SBC. MUCH more power potential and versatility than with the inline 6. You only have a couple or three manufacturers actively making inline 6 manifolds, headers, doing custom head work, etc., etc. And the specialty shops like Sissells Automotive charge ridiculous prices. A lump port racing head costs $1700! Sheesh! :rolleyes:

But if it's a six you want, then a 350 won't do. Me? I chose the six because I wanted to be different. Lots of people spend big $$$ on inline 6 performance stuff after surfing message boards like this, only to be discouraged after their friend blows their $3000 250 away with their $1500 small block. You can find their stuff on Ebay cheap.

My point. Make absolutely sure that you're willing to commit to the inline project through the end before you begin. You will save a lot of time and money.

-ftyler