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My C5 Cam & Supercharger Build Thread!


RoccoC5

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Ahhhh... maybe I misunderstood .... thought he said he had a pressure drop .... which could happen as flow increased ...... Isn't the pressure supposed to be in the 60s neighborhood ...... ???

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joe@cpr.com

Ahhhh... maybe I misunderstood .... thought he said he had a pressure drop .... which could happen as flow increased ...... Isn't the pressure supposed to be in the 60s neighborhood ...... ???

58psi is factory. He did have a pressure drop, that indicates something is not keeping up with his furl demands, he should not be running out of pump at 460 rwhp, so he has a blockage or kink somewhere. I highly doubt it's his bap wiring as the car would be having other issues.

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Yep, pressure dropped from mid to high 50's down into the 40's at around 5000 RPM. AFR went from 11's to high 12's at this point.

Thanks for the suggestions. I'll probably swap my filter as it's a few years old and pull the pump tonight to make sure the hose isn't kinked and that the sock isn't folded. I'll let you know what I find.

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I certainly see your point ..... My thoughts were more along the line of enrichment in those cells at 5k and up due to the boost ....

without seeing the data tho ... just a thought based only on almost nothing ...... :unsure

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Oh, and it was making around 7 psi @ 5K RPM so it looks like I'll probably end up around 10+ psi and outflowing my MAF. Nic suggested I convert to an SD tune, so I'll have to swap in a 2 bar MAP and get re-tuned.

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FWIW: I'm at 10psi after headers and 3.4" pulley. Nic was at the shop and didn't see a need to retune; however, with the cam, I'm dropping to 3.33 and going SD.

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I think I sorted out the fuel issues. Removed the pump and it did look like the filter sock was folded on top of itself and one of the two grounds on the underside of the pump hat was loose (not sure if the ground had anything to do with it, but I fixed it nonetheless). I replaced the sock and was careful to be sure it was positioned correctly this time. I also swapped the fuel filter.

Afterward I made a few pulls past 6K and the fuel pressure stayed above 50 psi. The AFR looks much better now, too. On the dyno we were seeing the AFR shoot up from mid 11's to the 12's at around 5500 RPM, and now I'm seeing high 10's and low 11's. Here's an export of my AFR/RPM/Boost data log of the last run:
graph.png
(As a side-note, I wonder if those dips in boost are indicative of belt slip?)
Now I'm just waiting on my 2 bar MAP sensor and then will schedule with Nic to do the SD tune and get it back on the dyno. Any thoughts on whether I should delete the MAF entirely, or just leave it be?
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What are you using to generate/graph that data?

Edit: I've been looking into MAF delete too. I *think* you have to do something about the IAT sensor if you take the MAF out, but I haven't invested enough time reading about it to say for certain. A&A has a nice MAF delete charge pipe.

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The AEM Wideband/Failsafe gauge logs several hours of AFR, RPM, and Boost data. Pretty handy for people like me who don't have a more complete data logging solution. :)

My IAT is separate from the MAF (I had to drill a hole in my charge pipe for it). I believe in 2001+ they went to a 5 wire MAF with the built in IAT, so you're probably right that you'll need to do something about it. I'm pretty sure SD relies upon air temp to calculate the air density.

FWIW, I asked Nic about deleting the MAF and he suggested just leaving it be but I think it'll look cleaner without it, especially if it's not doing anything.

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I'll take mine out eventually. I agree, it will look better--ooooh, and I'll get the extra 20rwhp for MAF screen delete!!%#%#@ WaHoo!

What gauge is it and how do you get the data out of it?

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Glad to hear you got your fuel pressure issue resolved .... am anxious to see what the new tune does for ya ..... :popcorn:

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It's the AEM 30-4900. http://www.aemelectronics.com/?q=products/gauges/failsafe-gauges/wideband-failsafe-gauge

It keeps a continuous 3+ hour rolling log which can be downloaded via USB. Their AEMdata software allows you to analyze it. Pretty neat.

LOL @ MAF screen delete :rolf

Mine is 'in the mail' It'll be here Saturday. Thanks for the idea. I'm going to have to get an AEM fp gauge now too because I'm OCD about that kind of thing. My auto meter sender looks to be shot anyway.

Did you do anything with the failsafe lead?

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Cool! I'm using the AEM 30-4401 pressure gauge which doesn't quite match the failsafe gauge, but it's close (Joe stocks these). Weird that your Auto Meter sender is acting up already. What happened to the GlowShift gauges?

I haven't done anything with the failsafe output yet. It would be cool if you could wire it to a solenoid to dump boost or something, but I may just have it trigger an external warning lamp and/or alarm for now. Let me know if you come up with any better ideas!

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Ya, I didn't see any identical FP gauges. After the header install, FP sender looks to have stopped sending. We had planned to use one of Joe's spares to verify it was the sender. The glowshits were pounded into a thousand pieces when they stopped working 2 days after install. So, yes, I'm making the rounds on gauges.

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  • 3 weeks later...

Latest update:

Met with Nic yesterday to switch over to the speed-density tune after swapping in the 2 BAR MAP sensor. Made a few pulls on the dyno and then the MAP reading started getting all screwy. On the last pull the sensor was reporting only a couple pounds of max boost when in fact there was much more, so it was running way too lean. It didn't look like the sensor blew out of the manifold, but maybe I screwed up the seal when I installed it. I didn't pull the manifold to swap the sensors, so I don't know. Going to pull my manifold this weekend to see what's up with the MAP and go from there. I may have to ziptie that thing in there. :thumbs

Anyway, the good news is that it made 565 whp in 104* temps on one of the earlier pulls. I'll be back at the dyno as soon as I get this sorted! :)

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  • 2 weeks later...

Alright, so I guess the third time at the dyno was the charm. :) Finally got in a few clean runs so Nic could finish up the tune. First, a quick recap of the tuning fun:

At the first tuning session the fuel pressure kept dropping into the 40's. Turned out that I was a dumbass and folded the fuel filter sock over onto itself when I swapped the fuel pump. Second time around, things are going good until the third pull when my MAP sensor starts getting all screwy and reporting strange values. Again, I was the dumbass here and picked up the 2 BAR MAP on eBay. The "authentic AC Delco" sensor was actually some knockoff probably from China.

Sooooo...today, after swapping to a genuine GM MAP :), all went well and we were able to make a few clean pulls (after Nic readjusted for the good MAP).

Ended up making 581/492.

dyno.jpg

I'm super happy with the results! I do wish the power came on a bit sooner, but I suppose that's the nature of a centri blower and maybe a bit less cam duration would have helped with that too (feel free to offer any thoughts on that). Anyway, I am going to do my best to not fiend for more anytime soon. Now it's just time for a car wash to get all this soot off of my car from my unfortunate parking choice:

Thanks everyone for the advice along the way and for following my build! :beerbang::banannadance:

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