Unforgiven Project

It looked good in the hole diggin' !!
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Unforgiven said:
No... All 8 pistons are destroyed.
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Yaw, I was thinking about 8 individual injectors. But the Holley Sniper is different.

Unforgiven said:
The HP numbers I used for calculating the pump size were alot lower than the actual HP numbers. That is some really good food info for thought right there!!!! I am going to try and recalculate some numbers to verify.
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Since you have BSFC numbers from the dyno run, seems you have some very precise numbers to
calculate the required fuel flow.
 
I found my mistake!!!!!
I was thinking this engine was going to make no more than 650HP.. so that was the number I used for all calculations.
On the Dyno, we made 750 average with 788 being the highest because the belt was slipping.
So this is from my build sheets:

The Sniper injection needs 60psi to operate.

To size the pump:

HP x 0.9 BSFC / 8 injectors then add 15% (saftey margin)

650 x 0.9= 585
585 / 8 = 73.125 lbs/hr
73.125 + 15% = 84.093 lbs/hr per injector

SO...I needed a pump with that flow

Aeromotive_brushlessA1000_flow.jpg

The above flow chart is for the A1000 fuel pump.
NOTICE it is gallons per minute!

So to convert: 1 gal/hr = 6.17 lbs/hr

The chart shows that the pump flows 1.8 gpm at 60 psi

1.8 x 60 = 108 gph

converted over to lbs/hr : 108 x 6.17 = 666.36 lbs/hr

divide by 8 injectors : 666.36 / 8 = 83.295 lbs/hr per injector. This is what the A1000 pump flows.

Being that I factored in a 15% saftey margin in my injector needs which was 84.093 lbs/hr....I felt this was close enough.

Where I went Wrong WAS: First.. I set my regulaor at 60 psi....thats what the Sniper needs to work.

I forgot that I needed to factor in the 1:1 (boost to fuel lbs) and ADD it to the regulated 60psi.

We were making 9 lbs boost so that ment I should have set my regulator at a 69-70 psi so when I was under boost it would allow more fuel as needed.
I was literally starving the engine!!

Second mistake is the fact that the motor was capable of 800HP.... I needed to recalculate the formula and would have seen that the A1000 pump was not big enough to support the fuel delivery needs.

At this point I am thinking that if I buy another A1000 and run it in series...It may fill the need . but I need to really think this one through!

One thing is for sure.....I am LEARNING the hard way!!! But I am learning!
 
Is the 0.9 BSFC above from your dyno run or from the article ? What is your BSFC ?

You should have used 6.5 lbs/gal, instead of 6.17 for E85

From the Article You Linked to Above

Gallons E85 to pounds: Gal. x 6.5 = Pounds
  • Example: 15 gal x 6.5 = 97.5 lbs.
 
Indycars said:
How do the spark plugs look, do they support your theory ?
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That is what puzzles me.... I dont know what the plugs are suppose to look like running e85
But what I seen was a cleaner than normal look.. with the heat marks ending on the bend of the strap, and two threads showed heat.
There where no speckles on the plugs. I even changed them before the last run. They where gapped at .040

Indycars said:
Is the 0.9 BSFC above from your dyno run or from the article ? What is your BSFC ?
Click to expand...

I do not have the BSFC from the dyno.... The 0.9 I used came from Aeromotive a couple years ago when I was researching pumps and calculations.

I just happened to run across that article above today.
 
Grumpy said:
remember alcohol; you must supply about 40% more fuel volume, that may require a different fuel pump or injectors
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Yes...But when I laid my hand on my buddies pure alcohol 10-71 blown 4.8 engine....I thought I was going to have frostbite!!! It almost hurt cause it was so cold!
And he is paying $2.50 a gallon where I am paying $10 for C85
 
T-Test said:
It looked good in the hole diggin' !!
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Thanks T..... you should have seen it when water was coming over the box sides and in the passanger window , when I took the wife for a ride!!!!
I was a little worried that she would never ride with me again ... but she was having fun! We pulled about 100' through that hole before we started to
to come up.. I think that was what did in the motor because we were spinning 6000 RPM's for about 30 seconds while the th400 was in second gear.
The engine died about 1 minute later.
 
Well it's time to find a/some sponsors for your rig and do like NASCAR Teams do--$1,000,000.00 for a 4" circle !!!
No matter what the cost and the mistakes you make--having fun and your wife loving it also is worth more than all the money in the world.
 
Grumpy said:
that may require a different fuel pump or injectors and with a supercharger you effectively need to boost fuel pressure,
to overcome boost pressure,
so if let's say you have 10 lbs of plenum pressure,
your 60lb of fuel pressure is effectively reduced by 10 psi to 50 psi at the injectors,
just like your valve springs that generally require a bit more spring seat pressure to seat the valves art higher RPMs,
as that 10 lbs of boost resists the valve closure.
let's say you have a 2.02 intake valve, that's roughly 3.17 sq inches of surface are fighting 10 lbs of boost resisting its closure.
so you've effectively lost or need an extra 30 lbs of valve spring pressure to close the valve at higher RPMs
Id also cut back a few degrees on total ignition advance, if you're experiencing symptoms of detonation
Click to expand...

Grumpy I beleive you have nailed it.
I can say I positively set the fuel return pressure at 60 psi... when it should have been set at 70psi. Combine that with the fact that
the A1000 pump was too small..... it was doomed from the start.
The damn thing is....I can honestly say that I do NOT have enough experience with injection or boost to have said to myself
"STOP" and readjust for the pressures. I just did not know.... until after the fact. BUT you can bet I know NOW!

Some people can call me dumb or stupid..... But a great man named "DRAKE WHITE" once said
"You can wait for a BREAK or BREAK down that door, cause it's that calloused hand, CRAZY plan, that makes that HISTORY"

I can only hope that other people who are reading this can LEARN FROM MY MISTAKES!!! (cause they are getting expensive)

I will always listen to wise men who are willing to educate another ...
 
Thunderbolt said:
If you have the injectors above the blower you dont need to add 9 psi of fuel pressure.
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???? i'm listening.

I would think that you would have to add more fuel under boost no matter where the injectors are.
But i am open to listening .

I installed the back up motor over the weekend. The blower and injection system is installed . I fired it up and it will not idle very long before it seems to run out of fuel and for a lack of better words.... backfires. By back fire , I mean its more of a pressure release , not an actual backfire.

I am reading up more on tuning the Sniper cause I am confident I dont have the settings correct. But last night while sitting out on the back deck, enjoying the slight breeze... I thought about the fuel system.

I was thinking that maybe .... the foam insert that is floating in the fuel cell is breaking down and plugging the fuel filters.

I have a 100 micron pre pump filter and a 6 micron post pump filter that is located 12" before the Sniper unit. Both of these filters are rebuildable.
So tonight I will pull them apart and see if they may be clogged with the fuel cell foam.

I am suspicious that the 6 micron may be too fine of a filter for my application also and may be restricting the flow. Most research I have done recommend a 100 pre filter and a 10 micron post filter.

Before I get comments on the timing.... yes it was correct and verified with the timing light. I did the static timing also to make sure the
ECU was in sinc with the Hyperspark distributor also.

Another possibility is the O2 sensor might be going bad. I am running two separate O2 sensors. One sensor is working with the Sniper unit... while the other O2 sensor (located on the passenger collector) is a stand alone with an AEM gauge.

I had noticed that the AEM O2 sensor was fluctuating wildly and then read dead lean.

I had mentioned how there was a fine fuel spray coming out the collectors. I am wondering if this saturated the sensors. I am not aware of what the effects of the VP-C85 (with a scent additive) have on the O2 sensor.

Anyway... I just wanted to update you guys on where I was at ....
 
Grumpy said:
all related info you posted might help
Click to expand...

I am pondering if that 6 micron fuel filter is a major factor.... We know that we need to feed the motor 35% more fuel cause I'm running an E85
fuel.... It would seem that maybe that filter was too fine to allow 35% more flow.
 
personally Id suggest a 10-20 micron filter with a good deal of surface area medium and AN#8 or 1/2" inside diam fuel lines,
that change eliminates any chance of fuel line or filter related restrictions,
to fuel flow leaning out the engine, of course, the fuel pump and injectors must also keep up with demand,
in an ideal configuration, the filter would be mounted forward of the engine, in the trucks engine compartment,
to allow inertial loads on the fuel mass to be reduced as a potential source of problems having fuel reach the injectors,
the screw-on canister filters similar to the picture below are available for e85
https://www.summitracing.com/parts/edm-260-16

edm-260-16_ml.jpg
 
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Thank you for the suggestion Grumpy. I was going to call the holey tech department today and see what their post filter recommendations are
for when using E85 fuel... I like your idea of going to maybe a 20 micron filter to allow more flow, but I would like to hear from Holley on the possible effects it would have on the injectors.

I am running a AN #10 line from tank to the post filter that is 12" before the Sniper.. I had to reduce it to AN#8 from the post filter to the Sniper
because of the fitting size on the Sniper.

The surface area in those filters is a good call... I am not sure what they are. The 100 micron is a Summit Brand with AN#12 fittings , and
the 6 micron post filter is from "E85 FREAKS" down in Florida..

I already know from calculations that the A1000 fuel pump was not big enough for the race motor... but it will be large enough for my back up motor.
It will only produce 400-500 hp with the blower on it.. I also reduced the boost output for the back up motor by changing the upper and lower pulleys.
so I feel the A1000 will be fine for this motor... I will add the Aeromotive Eliminator pump along side the A1000 when I rebuild the race motor this fall.

Also.... that fuel filter you posted will not work with E85 because of the paper element. The
elements must be made of stainless steel for E85 use.

oops .. sorry Grumpy.. I missed the "similar to this filter" in your post.
 
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