Need some ideas on what happened

[In-Tech]

What our plan is so far is to repair the engine and install egts in each cylinder ex pipe(hard to do with water cooled headers) we are going to check the reluctor wheel to make sure that it in the proper place and then verify as soon as we start it with a light. change to a typical mechanical water pump.

Hiya, all good ideas. Do you have the jig to check the reluctor wheel? I generally key my cranks/balancers for future use with a supercharger and then make a pointer to verify the timing is what I am commanding.

A note on the EGT, you probably know but try your best to keep the bung the same distance from the flange as well as make sure the depth of the probe is the same between cylinders(very important). The open end probes react the fastest and are best for dyno testing, the inconel sheath will last longer but is obviously slower to react. I have seen marine stuff handle continuous use at ~1650F egt although I don't like it. My turbo stuff would usually stabilize around 1450f when I am finished(many variables to accomplish).

By stabilize I mean the EGT has started to hover and dance a few degrees either way under full power conditions, definitely monitor it at light throttle too, even though the mass flow is lower. At under 100 kpa situations the intake will bounce more. Truly you want to use 8 egt and 8 wideband. What that can show(after tuning) is equalization of the AFR and see major changes in egt between cylinders. Now you are seeing different mass flow between cylinders meaning more work = more egt. Of course this happens no matter the kpa but more pronounced usually at lower kpa.

[mfdcar51]

Pump E85 varies all over the place for ethanol content. I have seen 33 to 66 percent ethanol. Never saw 85 percent

[Newold1]

Not real familiar with a boosted engine running E85 but if your total timing was at 22 degrees then I still surmise that at 22 degrees the engine was seriously retarded in timing by 12 - 14 degrees! With that much retard in total ignition timing I suspect that the EGT's went off the scale and smoked the valves and seats. If the valves were not Inconel which they should be, then regular 21-4N stainless are seriously allergic to that kind of heat!

[modok]

Yes I agree the timing seems suspect. 22 degrees at that boost sounds about right......... for a 3" bore engine.

[HaxbySpeed]

The typical LS chamber doesnt require a ton of timing, but I've found E85 takes quite a bit more then gas, especially if you're running a rich mixture. Sounds like you guys are getting set up with the right stuff to get some good data now. Dont be afraid to try running it leaner then what is commonly posted on the internet as well. On a 23 degree small block with 11:8 to 1 comp at 15lbs it made best power at 12.4 on the gas scale and 34 degrees timing. E85 is extremely forgiving and has a really big tuning window. But get it sorted before a long pull. With your super low compression it will be interesting to see where you end up. Please keep us posted. For endurance pulls I run the water pressure off the dyno pump. No way an electric pump will handle the heat. Let the rear steam vents drain constantly through a 1/4" or 3/16" hose as well.

[In-Tech]

Good point Haxby, I thought that would be a given but sometimes easy to forget the small stuff. Here's a couple examples of off the shelf stuff.

https://www.motionraceworks.com/product ... KoQAvD_BwE

https://www.summitracing.com/parts/sum- ... /overview/

Also, watch the tensioner on long loads. It doesn't lie about detonation or preignition.

[jet1]

The typical LS chamber doesnt require a ton of timing, but I've found E85 takes quite a bit more then gas, especially if you're running a rich mixture. Sounds like you guys are getting set up with the right stuff to get some good data now. Dont be afraid to try running it leaner then what is commonly posted on the internet as well. On a 23 degree small block with 11:8 to 1 comp at 15lbs it made best power at 12.4 on the gas scale and 34 degrees timing. E85 is extremely forgiving and has a really big tuning window. But get it sorted before a long pull. With your super low compression it will be interesting to see where you end up. Please keep us posted. For endurance pulls I run the water pressure off the dyno pump. No way an electric pump will handle the heat. Let the rear steam vents drain constantly through a 1/4" or 3/16" hose as well.

Very good points and yes the Mezier 55 gal per hr are only .17 hp. Not even close to supplying enough water for the engine in an open cooling system. Will make sure the rear steam vents are open also.

[jet1]

Holy! great ideas and lots of help. I really appreciate it guys! be a week or so before its back on the dyno but i will be incorporating many of the ideas suggested here.

As far as a water pump goes. This application is in a jet boat and we have an unlimited source of cold water supply at 150 psi. we usually either use a pressure regulator to control the block pressure or control it with orifices. Normally we will run 1 #8 line and split it to two number 8'ts into the front of the block and two number 8'ts coming out. this usually gives us about 18 psi block pressure and enough flow to keep temps of an 800 hp engine in the 140f range.

My thought for the dyno would be to have the two #8 outlets and then supply enough water to get the 15-18 psi block pressure. I am figuring if it is an electric pump it is going to have to be 3/4 to 1 hp or more to do it. much like a stand alone water well pump 110 v.

[jet1]

so another question regarding camshaft just because I am trying to look at everything. The cam is 244/248 @.050 and .368/.368 at the lobe and the rocker arm ration 1.8 putting the valve lift at .662. nothing crazy but the cam card is specing gross vale lift at .625. I am assuming with a 1.7 rocker. Eng analyser program mentions this as being high for the duration.

[rustbucket79]

What our plan is so far is to repair the engine and install egts in each cylinder ex pipe(hard to do with water cooled headers) we are going to check the reluctor wheel to make sure that it in the proper place and then verify as soon as we start it with a light. change to a typical mechanical water pump.

Hiya, all good ideas. Do you have the jig to check the reluctor wheel? I generally key my cranks/balancers for future use with a supercharger and then make a pointer to verify the timing is what I am commanding.

A note on the EGT, you probably know but try your best to keep the bung the same distance from the flange as well as make sure the depth of the probe is the same between cylinders(very important). The open end probes react the fastest and are best for dyno testing, the inconel sheath will last longer but is obviously slower to react. I have seen marine stuff handle continuous use at ~1650F egt although I don't like it. My turbo stuff would usually stabilize around 1450f when I am finished(many variables to accomplish).

By stabilize I mean the EGT has started to hover and dance a few degrees either way under full power conditions, definitely monitor it at light throttle too, even though the mass flow is lower. At under 100 kpa situations the intake will bounce more. Truly you want to use 8 egt and 8 wideband. What that can show(after tuning) is equalization of the AFR and see major changes in egt between cylinders. Now you are seeing different mass flow between cylinders meaning more work = more egt. Of course this happens no matter the kpa but more pronounced usually at lower kpa.

How do you control the heat, by altering timing and enrichment?

[mag2555]

Valves dump 75% of the heat they collect by conducting thru the seat!
If your seats are too narrow or the valves are floating at peak rpm, or even at some mid rpm then that alone can toast them.

[340king]

E85 MUST be mixed at home to be 100% certain of what you are getting. There are kits, hydrometers and such that you can buy to test the ethanol content of your fuel. The best way is to drive over to the ethanol plant with a 55 gallon barrel with the right amount of race fuel in it and mix your own, using the testing tool to ensure fuel ratio. The race fuel helps, especially in the lubrication area. Ethanol leaves the plant as E98. So it is blended down after the fact.

The other thing to understand is that ethanol is similar to methanol in being hygroscopic, it absorbs water. So getting the driest batch typically requires a short supply chain and sealed containers. Knowing someone at the plant also helps as they can let you know when to come out for the freshest batch. Fuel provides ALL the energy. Spending a little time getting it right is EVERYTHING to a racing engine.

I live 6 miles from an ethanol plant, so it’s easy for me to say this.

[peejay]

8.7:1 on E85?

Rebuild that thing with 10:1 or more. Or switch to gasoline.

[af2]

8.7:1 on E85?

Rebuild that thing with 10:1 or more. Or switch to gasoline.

In a boat whole different deal.

[racear2865]

I just got thru spending 3 weeks on dyno with a 540BBC with 8-71 blower on fuel injection on pump E85. Pulled pump fuel from 7 different pumps and varied from 51% to 77% as Ethanol. Spent much time tuning to not only making live but run for power. Had to put static ratio aat 9.1 and that is calculated down to top ring. Combustion chamber is "softened", which helped. Is 20% over driven(presently) but run higher. Dynamic is as high as 12.?. If we pulled timing back too far, egt temp was waaay waay out of control. You better do all u can to widen the tuning window..
reed