2.85 (2.9) Stroker with S50 Crank - it lives!

[sert57]

I'm not sure honestly, the car was always running rich and seemed to be fouling itself out even when running, when it stopped on me it acted like it was flooded. The exhaust also was very visibly rich at all times as well. For reference i was running p/n 0280155700.

Still getting CEL 1223 which I need to track down soon. It was there originally withe the ford injectors, went away when I got my exhaust finished up, and came back with the oe injectors.

Once I get the other injectors and make sure it really is sorted out in ill put it on a dyno and post results. My goal with this was to build a quality budget stroker using easily obtainable off the shelf products, and I feel like I've been successful. So once i know its sorted ill try to write a shorter little thread about what i did and what the results are. I'm hoping to get around 180 to the wheels with it.

[digger]

most likely a bad injector or 2. i ran "ford" injectors the same size as what you had on stock chip for weeks without issues on a stock m20b25 when diagnosing some things, probably not the same p/n though

[sert57]

Played around with a lot of variables - cleaned icv and afm and made sure they worked, my fuel pump pressure was a little low so i replaced it with a new meyle unit. Changed out CPS for another i had laying around and still didnt work.

Finally i put the oe i lnjectors in and it fired right up, perhaps the ford ones I was using didnt work well with the system, it had ran very rich. Going to try to return or sell them and I have some pink tops on order as i need the #19 capabilities. I could feel the oe injectors failing to keep up at WOT at high revs.

That seemed to fix the problems, no hesitation off idle, not hunting anymore, and not running rich. Hoping to keep breaking it in and get it on a dyno at some point.

[digger]

i havent played around with motronic and AFM for along time but revs jumping without throttle and hunting at idle sound like an ICV issue, but i bet this isnt the only issue

you should do the usual fuel delivery and pressure checks as well as electric checks for the fuel system (relay checks, power to pump etc) if you suspect something.

[sert57]

whelp she just left me stranded for the first time. It did something similar to when i got it to the exhaust shop yesterday.

driving around at ~2500 rpm in third, the engine started to hesistate and jerk a bit with no change in throttle position. It then began to at pretty erratically ( reving up to 3k with not input in neutral, and then hunting for the idle)

about 1/4 mile later she died on me, just shut off. I pulled into a parking lot with the momentum i had left and couldn't get her started again.

I'm suspect of the original fuel pump getting overheated from the increased demand. we got it running fine when it was back home - fired up first try with 37psi of line pressure. I'm going to try to replicate the failure and see what the fuel pressure is then. Any idea besides this?


There is still the hesitation coming off of idle that makes it ridiculously easy to stall, and the hesitation at 5.5k. havent done much research today as i was getting the PS system functioning and fixing a few other small things on the car.

car seems to be running very rich, Ill try to do an ECU reset in the morning and see if that helps withthe new O2 sensor.

[sert57]

She's running really well, today i had a custom center section made to adapt the headers to an oe catback hookup. Put a magnaflow resonator in the middle. I love the sound, its oeish at idle and really wakes up above 3k.

Only 2 main issues at the moment - there's a huge hesitation around 5.5k at full throttle, and there's a noticeable hesitation when applying throttle from idle which i have to either get used to or fix.

[sert57]

Yeah for now i just have an sssquid custom chip. MS will probably be in the future.

[digger]

gonna stick with motronic?

[sert57]

https://youtu.be/a_xd1pNa9eg

It lives

[sert57]

272 bimmerheads cam, hd rockers. Should help some with peak power without loosing much low end torque. Ie longtubes will also be included

[digger]

stock cam and head? should be a torquey SOB

[sert57]

Just got the 0.098" MLS gasket. torqued at 20 ft-lbs The Piston - head quench is about 0.047 - 0.050" measured via solder through the spark plug hole, seems right on the money to me ( only checked cylinder 1, I expect the highest gap to be about 0.056"

Cr is about 9.7:1

I'm onto final assembly and getting her in the car. exciting stuff. Hoping to have her running in a few weeks.

cam is times, valves adjusted, and i installed an I.E. oil pan baffle.

paring this with #19 bosch type 3 injectors w/ EV1 connectors ( i believe these are the mustang ones)

Running a custom sssquid chip for now, once I have more money i will probably go standalone MS2 PNP.

[digger]

I think this is exactly what water pumps do :p

Very curious to see where this ends up.

in this case it would be called a snail, but that doesnt count

[Dagamus(NM)]

you cant push water uphill

I think this is exactly what water pumps do :p

Very curious to see where this ends up.

[digger]

When i bought the engine it was from a 99k automatic, the PO had it torn down too do a turbo build on the stock rotating assembly. I know he had the head skimmed flat again, but i don't know how much. I measured the depth from the machined surface to the cat surface where the numbers are near cylinder 1 to be about 0.025"

It's weird the me that p2v was still reasonable with that setup though.

At this point it seems a .12" MLS is my best bet, hopefully raising the quench height by 0.04" ( to a minimum of 0.06) from the 2.05 HG.

IMO you want 0.040-0.050" quench, this is the consensus of many professionals in the industry, some advocate even smaller but none really advocate much larger than this for a NA engine.

since you have variability you'd probably want the smallest to be about 0.035" as a minimum so that needs 0.015" thicker (0.098" ????). the max will be 0.065" which is getting too large but it is what it is....