Nice improvement on the oil pressure reading stability with the snubber. Where is your sensor located? Mine does bounce around quite a bit, roughly +/-0.2 bar, located in an oil filter sandwich plate at the block.

 

I tapped the timing cover in the middle of the o-ring section. I think it ends up on the end of the oil feed passage before it splits to the mains.

I ran about a 12" -4an line to a t-fitting that dead ends to 2 sending units.

I might stick one of these on my fuel pressure sensor too. It doesn't fluctuate as bad, but it wouldn't hurt.

 

So my F90000285 "525lph" left me on the side of the road a few days back. Luckily a friend was nearby to drive me home so I could throw a spare 340lph pump in there.

I don't know if it was an electrical component of the pump or mechanical. So I took it apart and I still don't know, lol. I hit the pump against the floor with a 12v battery connected. It would hum differently every time I tapped the ground with it.

I also bought a F90000295 "535lph" pump to replace it and I'll probably put it in over the weekend. I know it doesn't have the check valve....so I will probably just set the "prime pump" time to 5 seconds or so. Or maybe it won't be a big deal with the default 2 second setting...we'll see.

















So I am figuring its either the inside part of the motor rubbing against these magnets(?) and binding....or maybe this positive terminal is having continuity issues.








I thought these small dents might be a defect before....but it looks like they just help keep the upper plastic section in.








Here is the check valve built into the outlet of the pump (right side of the first pic). It looks to restrict the pump quite a bit. I had to destroy it removing it but you should be able to see the difference with and without the valve. The plunger was straight before I think....I used a hammer and punch from the other side to drive/destroy it out.

















Here are the terminal connections for the wiring. The power side looks like maybe it wasn't crimped/riveted on as hard as the ground side. The indent is less visible than the ground terminal. I don't know if it was causing a bad connection or not. There is also some corrosion on the opposite side of the power terminal.














Also having some intermittent clutch issues. Seems normal when the car is cold...gets stiffer (20-50%) when things warm up. I think its either the master not sealing on the front of the piston when cold, or it is mechanical parts growing that much on the clutch side, taking up the slack of the clutch to throwout bearing.

I've gravity bled it....slow pedal push bled it....and pumped and locked the clutch and released the bleed valve....nothing so far has fixed the issue 100%. I do have generic auto parts brake fluid in it and it may not be new. I have heard of the possibility of water getting into it and making things inconsistent, so I have new fluid to go in.

I'm going to try a tilton .700" master cylinder and see if it helps the issue. I have a .750 wilwood but I have been reading that too many people have issues with them.

 

Interesting..... Are you sure it's a genuine Ti pump? I get my pumps from highflowfuel.com. They are supposedly the top distributer of the genuine Ti pumps in the US and their pricing is on point.

 

I think it is genuine. I've looked at a few videos/pictures of fakes and both pumps look like the "real" pumps. They were both ordered from Summit.

From what I could see the fake pump bodies were about a quarter inch shorter and the wiring was a bit thinner.

 

Yeah, if you got it from Summit, it's most likely genuine. I just ordered two of the 535's to replace the 450's I had. Carey said while we are finishing this build, let's go ahead and put the biggest pumps in it now so we don't have to worry about fuel down the road. I think two of these are good for over 1200 whp on e85.

Also noticed that Summit has these pumps cheaper that highhorsefuel.com, which is odd. I may cancel that order with them and get the pumps from Summit and save $50. Kind of odd since highhorsefuel.com has always been the cheapest source in the past.

 

Some little updates, not much has really changed. Have just been gradually increasing the boost pressure until I had a headgasket failure, which pressurized the coolant system.

Cylinder 1 had a small channel to a coolant opening and cylinder 2 was leaking quite a bit on the intake side.









Found that my manifold cracked in 3 different spots. Really don't know why other than "s2000 life". I drilled and channeled the cracks and welded them back up. We'll see how long it lasts.










Chasing why the headgasket failed led my to buying new injectors. I needed something larger than the 1300s I had anyway. I did have the 1300s tested later and found that they flowed pretty close to each other still (though I believe it was only checked at a single pulsewidth). Either way I started paying more attention to my logs and found I was getting some knock voltage spikes mainly on cylinders 2 and 3. And only really saw the issue above ~20psi.

I ended up getting a new fuel rail and added a damper as I thought fuel pressure fluctuations may not be helping. I was getting 20 psi swings at times in my logs. It has dropped to maybe 15psi swings at the worst....but this is the only data I've found that I can try and fix. Taking some timing out did seem to help, but I am wondering if I'm just masking an issue that still exists.

I am going to try and run a -8 feed line from the pump to the rail and see if that helps my issues.






A log of my fuel pressure fluctuations. Also my battery voltage drops to almost 13.0v in the higher rpm which bothers me a little bit.





I also bought the aem trim potentiometer and made a bracket to replace my convertible top switch. It will be nice to have some power adjustment without needing a laptop in the car.
















I also finally got the car on a dyno to see where the numbers were at. I made about 10 pulls until there were issues with a hesitation/miss was noticed. The graph's flat spot seemed to coincide with areas of heavy fuel pressure fluctuation. I did get a clean enough pass at 26.5psi though




Blue line is 16.5psi 536/386
Red line is 26.5psi 668/453

I am happy with the powerband and thought that it felt like it drops off harder than the dyno shows. I think the borg "6168" could go a little north of 700 before it starts to really die off.

 

What headstuds are you running?

I had a similar idea with my convertible top switch, but made a delrin puck and with laser etched numbers, that fits down in the pocket. Turned out pretty sweet, but I may switch to your route if I don't like how the knob sticks up. Wish I had a photo handy to show.

 

They were oem bolts when the gasket failed. I just bought arp studs that replaced them.

Yeah I tried to get the knob as low as I could and still be able to turn it.

The laser etched numbers sounds cool.

 

Those are some serious-looking clamps on your couplers! What are those?