Finally have the 540 running in the Demon

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airwoofer

airwoofer

Drivetrain limit explorer
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Huntsville, AL
It has taken me way too long but I finally have the new 540 (4.500 x 4.250) running in my KOS Demon. The car had a KB/B1 499 (4.530 x 3.850) that had huge ports and a pretty big cam with 15-1 CR. The 540 has 440-1 heads CNC'd and a R2 cam with 1.6 rockers and 14-1 CR. I have the same Dominator carb on the 540 that was on the 499 and for now using the same C-16 fuel.

Why won't the engine idle with the carb set the same as it was on the 499? Is it possibly the stronger vacuum pull from the larger disp requiring more air? I have had to open the idle stop quite a bit to get it close to idling. Timing? Right now I have it at 34* fixed from the crank trigger. The way it starts it does not seem to be too far advanced.

Haven't gotten it to the muffler shop yet and with open 3 1/2" collectors it sounds like a beast.
 
my 540 I had to tear it down,wasnt running right,had a lifter roller bearing go bad,and had some valves kissed some piston,so have to repair some stuff
 
This one has issues also. It won't idle because of internal or external drag on rotation. I am hoping it is as simple as putting a spacer behind the Powerbond balancer so it clears the Indy cast front cover. We already had to machine that cover some for clearance. I have .100 clearance between the vert and the flexplate so hopefully that isn't the issue.

This thing is gonna be pretty stout when I get that drag out so it will idle. Woo hoo.

Still need to take it back apart and cut the piston tops flat to drop the CR and maybe improve the quench.
 
Was it run on a dyno at all?
It should at least idle with the same settings - even if that idle was bad. Did I read right - you had parts rubbing on parts? Are you certain the rest of it was built right? seems like an easy thing to catch as a builder.
 
I have a Powerbond balancer and a cast Indy front cover. The balancer rubs the cover when the engine warms up causing drag which is why the engine won't idle. Guess we didn't clearance the cover out wide enough. An ATI spacer (#916370) should space out the balancer enough to get plenty of clearance. Then just re-set the spacers for the pulleys and timing wheel and off to the street for some break-in burnouts.
 
That spacer fixed the problem. The motor likes timing. The more I advance it the better it starts and the idle gets batter. Strange. The timing is locked in with a MSD wheel / pickup.
 
a 540 is super cool, 4.50" x 4.25" is great. if running c-16 why bother to lower comp. ratio? I don't see trimming domes down improving quench, if that is what u are thinking, run it
 
That's gotta be some mean grinding going on to mess up the idle. Especially a motor that big. Did you open the idle on the secondaries also?
 
I opened up the secondaries and that got the idle working - that is after I fixed the balancer hitting the front cover. Now the dents I had to put in the 2 1/8 step Proparts headers to clear the passenger side torsion bars (/6 I believe) and a driver side tube for the snout bar, have come back to haunt me. The uneven ex flow and backpressure caused a laminated ex gasket to blow even though it was glued on with red RTV. This was as the engine was trying to get through 6000 RPM. The power just isn't there like it was with the short stroke 499.

I am looking into getting a set of HDK coilover braces and getting rid of the torsion bars which are not needed anymore. The car used to run KOS and had to have stock front suspension. The tube for the snout bar will get moved.

Or I may get a set of headers made that are like the ones that were on the 499 - those are very well designed unlike these Proparts from TTI.

So close to making burnouts, but not there yet.
 
@ 14:1 you should pick up quite a bit of power going from C-16 to C-12...like about 15 or so.
Q16 would pick up even more but you might have to change metering plates to flow the kind of volume it needs...almost like alky!
 
Hehehe,,,,burnouts in front of your house. That's cool! Post pictures! That brings back memories.
 
RTV,that's silicone. Good for sealing things up. As an adhesive just so so. Want something to stay put? I like weather stripping adhesive. Just be sure you really want it to stay,,,for a long time. Just glued some valve cover gaskets to the covers earlier tonight. Try it on your header gaskets,you will have much better results.
 
I never had any luck with RTV or sealant on exhaust gaskets. Make sure the flanges are flat and there's no awkward pressure on the headers - they should fit flush to the head flange without using a bolt or bolts to draw the header in.
 
14:1 i rans 112 or 114...thru a carb love high compression.... then went alky when we put the hilborns on... very nice.
 
Hilborn stacks on alky. Super throttle response. Never foul a plug. Can be a bear to get both banks to idle/build heat the same. Anybody have em for a 440 they don't use anymore?
 
I started with C-16 and am now trying to get it to live with 114 Sunoco which is a little over half the price.

So close. This is pissing me off. Those headers were pretty darn expensive and I have to take them off and fix the dents I had to put in to get the thing running.

Yeah, I live on a long straight country road with nothing on either side but farm fields. I call it burnout boulevard. Starting to think it is about my attitude toward this car right now.
 
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