Cobrakiller1994 Chrome tuning thread

[cobrakiller1994]

I finally have gotten around to putting my car back together and get it going after 3-4 years. Originally pulled motor and trans to do a 120k service when I found a rod bearing that was about to spin. Turned into a full rebuild and the said 3 year project :worked_till_5am: So here we are now I have it back running and found out the 13Ts I had had a bent turbine blade hitting the housing. I upgraded to some 20T with 9 blade HL wheels.

Heres the full mod list:
Ray's 3.1 ross pistons
H-beam rods
Polished stock crank
ARP main studs
Clevite coated bearings
Brian crowler springs and retainers
Aftermarket headers
20T's
PTE 1000cc injectors
Walbro 400 e85 pump
-6 feed line tank to fuel rail
Honda style FPR
Dual core FMIC
MAFT in drawthru with 3.75 MAF
GFB BOV
RPS MAXX street
Full ATR exhaust

I have been driving it and have the fuel trims pretty settled out, they vary back and forth but so far I think I am in the clear. Start up is great. I do have a slight problem with off idle when its still cold, once warmed up it's fine and smooth. I think I might need a new IAC idle is pretty good but sometimes idles at different RPM.

After some miles getting trims good I started to do some WOT pulls, initially started out at 8psi and have been slowly upping it. Last adjustment before my drive home from work did a few pulls and I am holding 19-20psi. Power feels great obviously but I'm alittle worried. I am still stock fuel map and timing but I haven't seen even 1 count of knock yet. That seems like a good thing but I figured at that power level I would pick up a few hits. I have read and read multiple threads on here and the other site on tuning and feel like I have a decent grasp of it. I have gotten this far just think I could use alittle help to further the tuning.

Not sure how to or if i need to post one of my logs if anyone would like to see. I'm seeing 260 load and 3000HZ. These numbers could be off a little based on the fact that I'm running MAFT zeroed out but I am pretty close to the stock fuel map.

[Unlogic]

I'm pushing about 19 psi myself on essentially stock fuel and timing maps. I've only reduced the timing a few degrees on high load after 5500 rpm and leaned the richest part of the fuel map from 10.2 to 10.4.

Are you running on gasoline or E85?

What injector duty are you seeing in the logs?

260 load and 3000hz seem very reasonable, matches the values I'm getting quite closely.

[cobrakiller1994]

Forgot to put that I'm running 93 octane right now with plans to switch over to E85.

I'm pulling about 10.0 to 10.1 range WOT right now so I want to lean it out just alittle.
I have just see multiple people having knock at a lot lower loads/ power levels, seemed weird I have not had any.
Also, didn't log duty cycle yet

[cobrakiller1994]

I have pulled 2% out of 1600hz table and in my last WOT it was 10.0 and down in the high 9s which I figure is maxxing out the gauge. Should I take more out or go back to how it was? In the mids I had to take 4 or 5% out to get the trims settled.

I also tried to log my injector duty and seems not right to me. I am running 1000cc PTE but only seen 11%

[Unlogic]

You should try to adjust smoothing/ve tables so that the AFR value you get in your logs matches the values in the fuel table. A duty cycle of 11% sounds very low. It should be more like 50% given the size of your injectors.

[cobrakiller1994]

I pulled some more fuel out of the VE tables and now its at 10.5 but I only pulled to 5000 rpm so looking at the table that seems right. I will try to get some more done today. I lowered the boost a few psi until I get things dialed in. I'm not sure why it shows so low duty cycle. I have evoscan set to the same injector size as my tune. My plan is to get things right on this tank of 93 then fill up with e85

[cobrakiller1994]

Been driving the car around on e85 now for probably 1500 miles and everything seemed good except warmup accel could use alittle fine tuning. I got my coils hotwired so I decided to up the boost to around 22-24psi (all my wastegate springs would allow) car ran great and pulled like crazy. Went up to a car meet and did a few highway pulls against some cars. On my last one the car took off then acted like fuel cut and the A/F was pegged rich and would not come off rich. I cycled the key on the highway and stayed the same. Barley made it off the exit and into a lighted parking lot and popped the hood. Checked around for a blown off boot but found nothing. Unhooked the battery for a few minutes, hooked it back up and everything was back to normal. I drove 25 miles home cautiously with no problem.. Today I went out and was going to log some more and the car is still hitting a hard fuel cut. I raised the limit and the timer and flashed it in but still I cant go WOT. I was able to ease the throttle and hold about 15psi and it was fine but for some reason once I get into higher boost it cuts out.

[NOMIEZVR4]

great build! surprised I didn't see this before.

Do you have any virtual dyno plots with 24psi and e85?

I would start by checking vacuum hoses, mainly the hose going to the FPR. If a visual looks OK then proceed to a boost leak test. Keep us posted!

[cobrakiller1994]

It's been a long drawn out project! But I don't have any virtual dyno's yet couldn't get it to connect right.

I have checked everything and the car seems to run great just wont let me boost over roughly 18psi. I think i read someone else had this same problem awhile back. Its acting like fuel cut as the car just goes from full power to shutting all power off.

[FluffyCow]

Mine was just doing this at 15 psi on 93. Had a chunk of crap stuck in the inlet fitting of my fuel filter.

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