Inliners International Forums General Discussion Hi Performance Dyno day for a 292, Need help

It's irony that the aspect of the 292 that makes it an amazing engine, is also the limiting factor to gaining high rpm horsies. Ah well, how many people wind an engine to 6k+ on the street anyway?

Tom, you've done us all a great deal, and given us real numbers to put with parts. Even if the biggest cams don't get tested, we all know more than when we started, and I think that's the whole point.

So, thank you. And I'm especially looking forward to the next batch of numbers to start making conclusions about what'll make a nice street thumper.

-Sam.

If the big cams don't work until the higher rpms that we're not supposed to turn on the street, and we are trying to look at street engines here, maybe we learned that we shouldn't be wasting our money on too much cam. Bill Fisher spent some time in his book saying to be honest with yourself about what you really want your engine to do. This is hard for us. We are all willing to give up some drive-ability for some zip but somewhere there is a limit. ( I think ) Douglas's Brazilian Bomb is probably not what you want to take on the Fall Leaf Cruse, unless the drag strip is tree lined. Beater

It just depends on what you are willing to sacrifice. I have built several 8 second 1/4 mile street cars for some guys here, because thats the kind of power they wanted. One was even an NMCA car that got driven with slicks and open headers every weekend on the streets here when he wasn't at a race. It just depends on what you consider too radical or not radical enough.

It also depends on what "drive" means to you.

I think we all want the best of both worlds, power brakes, a/c, heat and all the comforts of a Cadillac, and the most power we can get and still retain all those other comforts. I think we have found that with the 292, 300 HP and 300 ft.lbs. of torque is pretty easy to get with just average off the shelf products. And still not overstress the engine and have good street driveability. We think the 250 is going to surpass that mark on the HP #'s, and still show to be a good streetable powerhouse.

Another update,
Today afterwork, installed the next cam and last cam to be tested. This is a custom grind with .521/.512 lift and 218/212 duration @ .050 and 114 Lobe separation. Good turbo grind.

The head is the same tested with last cam and is a open chamber design with 72CC chamber, 1.94 intake and 1.60 exh. It is mildly ported and has bolt in lumps.

After this head is tested, a 1.84/ 1.60 head with 70CC chambers will be tested in a backup test.

The engine will be run for the last time on Saturday .
Tom

Wearing me out just thinking about all that work!

Good luck Tom.

Can you see the light at the end of the dyno booth? Good luck today and thanks again. I'm sitting here by the fire in my recliner watching college football and smelling the second Thanksgiving dinner cooking. I'll think of you occasionally.
Beater

Thanks, Sam, Erik and Beater
Beater you will never get 4 or 5 piles into one at that pace!

Finally done with the 292 for now. Ran it as I wanted with the 2 different heads and cam #5.
Found a HP difference between them as expected. This cam did not perform as well as expected. When I put it in there were 2 cam bearings looking rough. In fact the old cam had to be persuaded out! That has to be eating up some of the power. Oh well the engine survived. Now to take it off and freshen it back up. Data will all get compiled now and sent out next week to you guy's that have supported me so well.

Like to say THANKS to my local chapter. At our last meeting they voted to also give me some financial support. AS of now there are about 45 inliners that have dirrectly supported me. From 5 different countries! This has went over much bigger than I ever expected. Thankyou all!

I will post more here than has been. Like to get into the INLINERS magazine and another publication first. Tom

"Beater you will never get 4 or 5 piles into one at that pace!"
Two of the piles are under snow today and there's no heat in the shop. That's a good enough excuse for me.
That engine has earned a rest. I guess you have too. You've been turning a lot of HPHs. (Heads Per Hour) Beater

So prying minds want to know Tom, what is the ultimate combination for streetable power????

Jalopy,
The paperwork is still at "the lady's" getting averaged out. Might get it back on Monday.

But here is the combo that proved to work the best. Highest HP, not highest tq. 280HP and very streetable.
Clifford Intake
600 Holley carb
Clifford 270 Hydraulic cam
292 open chambered head, HI-FLOW bolt in lumps, ported with 1.94/1.6 valves, roller rockers
Headers

There of course were many more combo's . Will wait to discuss those. So many theories were tested and need to be discussed also.

Tom

Since you mention it, what was the highest torque?

Not nit picking, just curious.

Without having the paperwork in hand. Seems like around 320 ft lbs or alittle higher with a smaller cam.
Or were you refering to this cam?

Got the averaged tests back today! Will get them emailed out this evening. Tom

Before Tom got on the dyno I proposed a bet that the 292 would not match the 4200 on power and torque...

Well we're both 1/2 right..

Bone stock 2006 4200 - 277ft/lbs and 291HP - mind you this is in full emmission trim and with the stock exhaust system. So not quite apples to apples.

I know I pickup 23 HP and 15 ft/lbs going to open exhaust during my 4200 engine dyno session earlier this year.


Lets see a good 2006 4200 can be had for about $1000-1500....

On another note the 4200 won't last for ever GM canned production 1 year ago.. Time to start stocking these away.

The early 235-261 are getting hard to find, bet the 230/292 are not far behind. I've only seen 2 292 in the past 5 years show up at the wreckers. Tom can tell you where one of then is....

I guess my point is the 4200 is most likley the future of the GM 6 as early engines disappear.

Just a quick question,how much did you spend all together w/the sleeves ,boring,cams,porting ,valve job,,, etc for the 4200 complete build?

Just so I can get an idea how much all the custom work & parts cost?

Thanks

MBHD

These 292 dyno tests pretty much all held over 300 ft lbs tq from 2500-4500 rpm. All cams did that except the stock one.

If I put a ad in my local farm paper, get 5 calls with 292's to get from combines, trucks and ag equipment. Most are allready pulled and stuck in the barn.

Tom

Sent out the dyno reports for the second batch of runs. let me know if you were missed. Looking forward to hearing from you guy's. Tom

Thanks for the dyno reports. Makes me wonder if lump ports are needed on a supercharged engine.....

Tom, I got the final sheets and the info will save me and others time and money with our builds. Thank you!!!!!!!!

If you print those all off and compare them. There is some interesting details for sure.

Sorry about the tq drop at about 2800-3800. The secondaries were opening too soon, but this had no effect on max HP. Could have seen about a 5-8 lbs increase in tq without that.
For the 250 runs this will be taken care of.Tom

Tom,

Do you think LP pistons would have bumped the numbers up any, and if so, how much?

-Sam.

Dyno day for a 292.......301 Replies...... 7175 Views !!! Now, that's a great thread. Needed some more just like it so this board don't just sits dormant for days....Jerry

Jerry is absolutely right. This thread has livened up this place. Thanks Tom and Scott for turning on the light! Beater

Sam,
I think the Lp piston would be a better way to raise compression to get performance. Also milling a open chamber head would be good.
Probably another 10 ft lbs with the bump in compression. Some say a 3% gain per point. Maybe more. You saw the #'s with the "194" head?

Scrap and Beater,
This has been alot of fun and really helped put #'s with performance mods done to the 292.

After the article is done and another done for the INLINERS mag, then I will post a summary here on the BRD. Really like to see as many become full fledged members as possible. There is alot to gain for us all. Tom

I'm in the process of printing out all the #s. Some very interesting findings! What is great for me is to see that I was pretty much on track with my build using Information gleaned here from those who really know. Just goes to prove that this BB is the spot for us to meet. Just a few bugs to squash and we can get on with it. Beater