The Stovebolt Site Forums The Shop Area The HiPo Shop 292 Hop up - virtual build

Anyone care to discuss a 292 virtual build? I've been wanting to do a hopped up 292 for a while now and that Hot Rod article has added fuel to the fire.
What would you do for a reliable, daily driver 250-275 HP 292?
Now, I sure don't know much about the internal workings of a motor, especially performance wise but, I hope to get a discussion going here and learn some stuff.
Seems to me after reading above mentioned article and trying to decipher Leo Santucci's book, the 3 biggest factors for performance gain would be cam, a better flowing head and fuel delivery. Agree?
-How much lift for cam is too much for a daily driver? .470, .480?
-Is lump porting for racers only?
-Are roller rockers beneficial on a 250hp street motor?
What would you do/what DID you do for your hopped up 292?
Let's build a virtual 292: I'll bring a ready to build bored 030 block.
And you'll ad...
-David

David, i think those numbers are attainable, even with my limited experience at this engine stuff.

and lump ports aren't just for racers, it helps improve head flow regardless of applications.
check out www.inliners.org there is plenty about hop up over there.

BUT.

a virtual 292. would have...either triple deuces, or triple quads. dual exhaust out of headers. glass packs. Twisted 6 lump ports. a good low end build. and a bullet proof tranny to back it up. sorta like a SM-465, but only with OD. lol. and what would it be in...does it really matter with an engine like that!??

.later days.
.desperado.
.sam.

OK, on the fuel issue. We're talkin' reliable daily driver here. So, 3 carbs for some people might not be a problem but, for more practicality, a single 600 cfm 4 would be in order. If money were no issue (and of course in the real world it always is) an EFI setup from Sissell's showed about a 30hp gain over a single 4 carb on the dyno. Complete fuel injection kit is $2000+. Um yeah, I think a carb will do nicely.

Do we need to lump port our head to get 275hp (I decided 250hp is not enough)? Or can we just have the head reworked without lump, saving money for elsewhere? What about oversize valves?
Maybe we should start the build from the bottom up?
And oh yeah, there's a fresh crank to go with that .030 over block mentioned above.
Who else is bringing something for the build?
-David

Nitro

I'm (slowly) building a fuel-injected 250. It has flat-top pistons and a fairly aggressive cam. When finished, it will have an NV4500 transmission behind it - durable, granny low, OD...can't beat it.

275 H.P. out of a 292 is easy but costs a few bucks. Lump ports help flow numbers but aren't needed for only 275 H.P. Just a nice port job and a bit bigger valves with a good cam of about 460 to 480 lift with a 600 cfm 4 barrel and headers will get you near there. My 3 Weber with that cam and big valves and tube headers makes near 325 H.P. With lumps and more cam etc. the 292 can make upwards of 400 H.P for a street engine. The 6 cyl. sound is music! I am an Inliner club member, it is great for us I-6 guys.

If you guys are really looking for a cheap, quick, easy way to get 275 horse, Joker hit the nail on the head. Go for a nitrous kit from NOS. You should be able to get 75-90 horse above stock without even tuning the engine around the system. If you put in a cam, head, and a 4-bbl carb, an additional 100-125 horse should be no problem, and 150 or more is possible, but you'll either have to build the short block to the power, or expect the mill not to last quite so long.

Yes but you have to be careful not to melt the stock pistons or break a ring or ring land. Aside from that, the nitrous oxide can certainly boost the torque, and to some extent, the horsepower, but the big horse numbers come with improved rpm capability. If you can only take your I-6 up to 3500 rpm or so, that's your limitation.

I like how the article attacks the I-6's problems head on, by improving and upgrading the strength of the rotating assembly, and improving flow through the head. That's huge. That with a good cam to optimize your newfound rpm range, and you can get a bit better than 1 hp/ci. But I don't think you'll get 400 horsepower without squeeze or some kind of forced induction.

It depends on what we're going for all out drag spec's or long life power. If you look at the dyno part that thing makes 304 lb-ft at 2400 rpm & never dropped below 290 from 2300 thru 4500 rpm. Build the bottom end super strong, mild porting, bigger valves, cam it for more low end torque, & limit rpm range to under 5000. Be neat to find factory TBI set-up from late 80's Mexico 292 to see what it's limitations are. Torque is what gets things going. That's one thing 6's got going for them. GMCpanel, What kind of fuel inj. you using?

Nitrous oxide burns like CH3No2 (methanol) straight across the piston. Gas will burn the piston at a pin point.

Nitrous doesn't burn- - - - -it's an oxidizer. When it encounters the heat of the combustion chamber it breaks down and releases oxygen into the mix. Use plenty of NOx, but add enough fuel that it gets burned- - - -not the pistons and valves. Hot oxygen is like a sailor on shore leave- - - -it's going to combine with something RIGHT NOW!
Jerry

CH3No2

Don't know what that is, but it's not an alcohol.
All of them are related, and have very similar molecules:
Methanol CH3OH, ethanol C2H5OH, isopropyl C3H7OH, butyl C4H9OH, etc.

If this guy can make a straight 6 Thriftmaster do this, then I would think you can.

NAPCO burnout

Granted those are skinny tires, but geez.

Sorry about the post I am brand new. Lets start again. Nitrous with gas will burn straight across the piston. Methanol and CH3No2 that is nitromethane will burn straight across the piston. The piston needs to be pushed down the cylinder straight not like the gas fired motor that pinpoints the piston.

Source of this information is...?

I have ran both nitrous and nitromethane. I still have the old Marvin Miller system back in the 60's. I build my own jets for nitrous. I also have a set of Hilborns and my hydrometer.

Yes, and the source of this information is...?

I built a 292, crower stage 3 hydraulic 262/480/490lift, bigger valves 1.94/1.60, edelbrock 500, harland sharp rockers, lumps, ported/polished, mallory distributor, I used LP pistons shaved the block&head for a true 9:5/1 comp ratio, took the head to 70cc's, langdon exhaust flanges and clifford intake, balanced all, with a saginaw 4 spd and posi rear 3:23 gear, let me tell you that motor "GOES" i have it in my 1953 chevy 3100, now mind you I could of built a super small block for what I have into it, but everybody has small blocks, you have to pay to be different!!forget the virtual just build it!!

And forget the nitrous. Yes it makes hp and torque, but only till the bottle runs out, which is about 5 or 6 passes at the dragstrip. Nitrous is for dyno numbers and race cars!

Joe

CH3NO2 is

http://en.wikipedia.org/wiki/Nitromethane

Nitrous with gas will burn straight across the piston. Methanol and CH3No2 that is nitromethane will burn straight across the piston

Still waiting for the news flash?

Back to the beginning: a reliable daily driver that's a little "hot"...that tells me pump gas and an air of coolness, so maybe we should limit our discussion to those criteria.
I know that some here don't like the multiple-carb setups, but Speedway has a cool-looking 3X2 setup with progressive linkage and carbs that are better than the old Strombergs, including optional Demons. I think they're 205 cfm each.
The lengths of the cam and crankshaft introduce the likelihood of twisting at high loads, so the max. rpm should be limited to avoid problems, and the bottom end should be as beefy as possible.
I remember reading about a guy who campaigned a 6-cyl. Camaro, and won regularly...many years ago, maybe Hot Rod mag.

cm

the bottom end should be as beefy as possible

What do you suggest?

Forged vs. cast crank, if available. ARP bolts where possible. Naturally, we're assuming the block and caps are as good as possible. It also appears to me that H-beam rods are stronger and lighter than I-beam rods, though I've never used them.

What would you suggest?

cm

Like this for the beefy.

http://www.cdpautomachine.com/leo/assembly.html

starfire4, the forged crank is a 6 lobe crank, i think, so it may or may not be a better choice. i would say the arp connecting rod bolts might be a good use of money just for saftey sake even though the 292 ones are a little larger. the aftermarket con rods and head bolt studs and welded head in handtight's link might be a little costy for a street engine. but hey if you got the cash....do it.

Yahoo! Sweet, but yes, all that aluminum is $$$!

cm

H beam is going to have a cam clearance problem.