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Discussion Starter · #1 ·
I am putting a 2.3 Ecoboost into an elise, build thread in other builds if you are bored, basically 2.3 crank, 2.3 manley rods, 2.0 Pro pistons from Speedperformance, Piper rally cams (11mm lift inlet 272 degrees) and lightly ported head. GTX2867R turbo in external tial 44mm wastegate.

But had some issues on the dyno, see below





First thing, is the vacuum pump. As i dont have a servo leaving it open to atmosphere builds pressure in the crank case, Blank it off and / or remove the drive gear and no pressure in the crank case. Any ideas why this would be ?

I had an 11psi spring in my tial wastegate, that on my previous engine hit 11psi on the nail. Fitted to the ecoboost it hit 2 bar and they had so much det they backed it off with no added boost from the controller. Took one spring out, should be 4psi and it hit 20psi.

Lastly at 20psi the engine was detting like a bugger so they had to retard the ignition, they did this until the EGTS started going through the roof. Could this be compression ? The engine is a 2.3 crank, 2.3 rods, with Pro pistons from speed performance that should give 9.3:1. I thought the engines used the same pistons and had similar comp ratios ? any idea if my combo would increase the
 

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If you used ecoboost rods you should be here

Untitled1.png

Mazda rods and you'll be here with stock head gasket and no piston mod

Untitled2.png

Also going to depend on what pistons you used. The propaks come in 9.3, 10 and 11:1 compression ratios
 

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Discussion Starter · #3 ·
Many thanks

Rods are manley 14424—4 Google says Ecoboost 2.3 so I'll assume that's them

Pistons, I don't have the box but an old picture says. Comp ratio ordered was 9.3 but for the 2.0


 

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Many thanks

Rods are manley 14424—4 Google says Ecoboost 2.3 so I'll assume that's them

Pistons, I don't have the box but an old picture says. Comp ratio ordered was 9.3 but for the 2.0


Well compression should be at 9.5:1. So your having this issue with the rally cams in?
 

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Discussion Starter · #5 ·
Yes, that's correct. If I have the correct ratio pistons

How do I know what the Mahle part no is for the comp ratios.

Also Deadhook racing state 10.6 to 1 on their website for their 2.3 stroker, my engine builder estimated the same. Did they use the mazda rods?
 

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Yes, that's correct. If I have the correct ratio pistons

How do I know what the Mahle part no is for the comp ratios.

Also Deadhook racing state 10.6 to 1 on their website for their 2.3 stroker, my engine builder estimated the same. Did they use the mazda rods?
That is true if you use a piston/rod combo that gets you closer to the deck and if you bored the cylinders. The Ford 2.3 is 0.078" in the hole at TDC, all ecoboost/duratec blocks are 9.094" deck height and the stock gasket has a 0.030" compressed thickness. The heads have a 43cc chamber. The builder should have easily calculated that and cc'ed the piston. This was why I suggested 30mm exhaust valves. The 2.3 uses them as well as the new 2.0 ecoboost with the same 43cc chamber. The head exhaust ports are not as restrictive as you might think. I ran into the same issue that you have with the first motor I built and I suspected it was the cams but you proved that to not be the case. With the second I took no chances it got long duration cams and exhaust valves.
 

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Discussion Starter · #7 ·
260 odd degrees is not that long though

So why the larger exhaust valves what's the theory behind it, dynamic pressure is built before the valves open regardless of size. Or are you saying they are not big enough to release all the pressure and it builds?

What was the spec of the first vs second engine?
 

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