Re: Unique Engine – More Power Needed
Posted: Mon Oct 11, 2021 9:57 pm
Are you sure those headers aren't too small?
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Couldn't he try the 3 x 2 bbl carbs he plans to use on the tunnel ram, on an IR manifold, instead of trying to find the Webers? Fabbing the IR manifold would be about like making 3 sets of 2-cylinder headers (he says naively ). Could even try that setup with gas and then methanol before making any other changes, to get some experience with tuning.PackardV8 wrote: ↑Mon Oct 11, 2021 3:05 pmOne could accomplish the same IR tuning with a pair of the old 3-bbl Webers, but they're hen's teeth and learning to get them right is a too-long process.
How long would the runners have to be to effectively have the same isolation and ram tuning on a plenum as an IR setup? With a 5500 RPM limit, that wants 16" or longer runners, doesn't it? (84,000 / tuned rpm = runner length measured from the back of the intake valve to the start of the radiused entry of the runner with the port cross section area 83% of the valve area in the intake port and taper out at a 3.5 degree angle as it goes toward the entry of the runner.)
Well, I'll preface by saying Engine Analyzer Plus (the one I have) is not a *true* simulation. It's a much simplified program built to be fast and easy, but not insanely accurate. I'm also not an engine builder, just a very analytical hobbyist that bought the program for funsies. That said, here's what I got as specified and then with it auto-optimizing simple stuff for average power across 3500-5500rpm.mn77spl wrote: ↑Tue Oct 12, 2021 5:47 pm I want to thank everyone with there feedback so far, in particular 'maxracesoftware' for all the time spent modeling. (BLSTIC I hope to see your analysis also.)
A couple of comments on what has been provided to date:
- Original valve size was 1.625 Int & 1.516 exhaust. Getting the port sizes up to where I would like them is a big challenge! I do however have ideas. . .
- A crank scraper is something I have thought about however I haven't come up with an approach. Perhaps a screen or louvered cover below exposed crank would be an improvement?
- If am am successful in fitting a 2.100 int (10% more area) with appropriate port sizes, I expect to be able to achieve a 10%+ improvement in flow. Can I then reasonably hope for a 10% improvement in torque? or am I dreaming
Original valve size was 1.625 Int .... and you were able to install a 2.000" inch Intake ValveOriginal valve size was 1.625 Int
It's a tractor engine, usually lot's of meatmaxracesoftware wrote: ↑Wed Oct 13, 2021 3:58 pmOriginal valve size was 1.625 Int .... and you were able to install a 2.000" inch Intake ValveOriginal valve size was 1.625 Int
and not hit water .... that's amazing !
and now you are thinking about installing a 2.100" Intake Valve ,
i don't see how a Cylinder Head could have so much metal + have enough Valve Guide CenterLine spacing
to install a 2.100 side-by-side with a 1.650" Exhaust Valve
your Cylinder Head seems like it has not much of a waterjacket , if thats possible to use those larger Valve diameters .
No known Cylinder Head i've ever seen would this be possible to do !
.... likewise above , same thoughts i have for the Intake Port itself !
i had originally "Diesel Flat Chamber" choice but i changed it to "Large Open Chamber Wedge"- What valve or cam lift are the timing recommendations referenced to?
- What engine configuration is assumed for the estimated power & torque outputs, "Race Engine • Mid-Range Peak TQ • Hi RPM Peak HP" ? or ?
- I would think the "Diesel Flat Chamber . . ." would be a better match for my engine as opposed to a "Large Open Chamber Wedge".
Substituting the Diesel chamber reduced the recommended overlap. Any thoughts on this
for the "Flat Chamber" or "Diesel Flat Chamber" , this was setup for Diesel Fuel with Turbos with hi Compression Ratios like 18:1 to 25:1Substituting the Diesel chamber reduced the recommended overlap. Any thoughts on this
that Choice seems to me best fits your Engine application,What engine configuration is assumed for the estimated power & torque outputs,
"Race Engine • Mid-Range Peak TQ • Hi RPM Peak HP" ? or ?
referenced to most of your PipeMax inputs and choices .- What valve or cam lift are the timing recommendations referenced to?