I've been teading alot and watching videos but i cant find any build sheets. I'm trying to end up with about 300-320hp from my chevy 292. I know i will need head work done but how much and what compression pistons and how big of a cam.. roller rockers or no? So many questions. I want to start collecting parts but dont want to waste money where its not worth it
If you don't have this book, get it. https://www.amazon.com/Chevrolet-Inline-Six-Cylinder-Power-Manual/dp/1931128154
You're talking significantly over 1 hp per cu inch, for a long stroke motor that's an impressive goal.
Significantly ? His upper goal is slightly under 1.1 HP /cu.in. It isn't worth doing the math over his lower number.
Getting 300+ HP out of a normally aspirated iron headed 292 will be a tough $$$ job. But you can get all the info on what it will take to get there from the experts on Chevy six performance, Sissells Automotive, down in California. www.sissellsautomotive.com They have done it. Also, check out the 7 page article in the June 2005 issue of Hot Rod, "The Joy of Six", where you'll see dyno results from both a 292 and a 250 along with the low down of all the goodies it took to get there. A lot of "build sheet" type info there. As mentioned, a supercharger or turbo can also get you the numbers you're looking for, but that's a whole different ball game. Although it's a completely different engine than a 292, the 261 pictured in my avatar (more pics in my albums) with a lot of mods and a supercharger, put out over 300.
Well, I said "significant" not monster, and I was looking at the 320 number. But to me anytime you're pulling 1 hp per cu inch you've already got a strong engine. Do it in an inline 6 with a long stroke and that's already impressive. Now start adding power above that, it's not easy. Maybe I'm just impressed easily. Why is this a point to argue about anyway??????
Im not arguing.. and you are right 320 would be close to 10% i was looking at 300 and always thought 1hp per cubic inch was a very attainable amount. Although i dont know alot about inline 6's. Thats why im here asking. No harm done.
It's easily attainable in a short stroke high rpm engine, not so easy in a long stroke slow engine designed to make lots of torque down low. A 283 engine making 320 hp is a hot rod. A 292 making 320 hp is tire shredding smokin' hot. Like I said, maybe I'm easily impressed, but that would do it.
I shipped a head out to be done down south where they still run them racing. Decked 020.0 Lump Ports done .550 lift springs Block machined and .030 over pistons with everything it should be 9 1/2 to one compression. I spent over $4500 to get to this point and I don't even have a project for it. Too many engines
Horsepower is a mathematical calculation, torque is a measurement. Torque is what moves the vehicle. Sure, 400 hp at 6000 rpm gives bragging rights, how often does your street car see 6000 rpm?
Does anybody recall some guy that put small block heads on a straight six. I know I saw it somewhere. I think he took two heads and cut one cylinder off each and mounted them on a 292 motor.
Torque engine. not a high RPM high Hp engine. Certianly you can build it to have a certain HP. All it takes is a lot of money. Its simply not very prudent.
First I would think about what you are wanting to achieve with what you have as a starting point. From what I found a 292 with 8.5 compression makes 165 HP under 4000 rpm...So you want to double it. A great stock 62-65 327 makes 300 hp from the factory and if you wanted it to make 600 hp what would you do? That's it in a nut shell. I've been building 302 GMC 6's since 1976 (which made 160 hp stock and different I know) and run 171 mph on gasoline at Bonneville and 159 at El Mirage with stuff you may have never heard or thought of and have never been on an engine of chassis dyno but I would be estatic with 300+ hp. The 311” in the photos has 10.1 comp, .440” lift cam, 1.94/1.60 valves and what you can see and I would be real happy with 220hp even 200. For what you want you will need some pretty good head flow numbers, light valves would help, along with springs, some rocker arms that don't move all over the place, roller cam, outside oiling, etc... A concern is your 4.125 stroke and rpm. Don't get discouraged but think about the power adders listed above.
It's pretty easy to move inline six hp to a certain point think if your V8 had a small one barrel carb and a restrictive log exaust manifold.
If I were building it, I would build for torque and let the horsepower fall where it does. Take advantage of the long stroke on that 292. Consider this, a popular 15 liter diesel makes 475 horsepower, but makes 1500-1600 foot pounds of torque. Granted it’s a diesel, and turbocharged, but sixes are torque engines. A turbo on that 292 would overcome a lot of design inefficiencies in the cylinder head. Sent from my iPhone using The H.A.M.B. mobile app
You can build a cross flow head by welding 2 v8 heads together with one cylinder chopped off each head. Not a simple mod but probably a better head than any modifications you can make to the original head. Sent from my iPad using The H.A.M.B. mobile app
Thanks....It's currently being installed in our 40 Chevrolet drag/LSR coupe which is going back on the street where it has not been since 1962. Our son is doing it .
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