Haha what do the perfect creases in my Dockers lengthen? I guess I should have simply said that the pump works as it should.Understandably a/f ratios are not the sole indicators of proper fueling...on another note however, anyone running 10's and 11's a/f at wot are wasting fuel.
PT-Performance Pump in
- Thread starter zx2man
- Start date
. . . but keeping combustion cooler, reducing detonation risk and maybe saving the engine??
I'm really unconfortable with AFR's at WOT under load in the 12 or higher range with this engine. Maybe that's just me being too conservative. Don't want to zoom, zoom, boom.
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Darth Vader
Member
12+ AFR at WOT in a boosted car is a guaranteed blowup, sooner or later. I wouldn't set a turbo car at anything more than 11 to 1. You can pull off the 12-ish to 1 in an N/A car but, not a boosted one, the loads on all parts of the rotating assembly are just so much higher.
Darth Vader
Member
Mine was frequently 10:1 with a CAI, Forge bpv and CS downpipe...with a dying CDFP, no less. Expect that, or even 9s on a stuffed up stocker....(boom01)
Saskatchewan17
Member
- :
- 2008 TR Mazdaspeed 3
I've heard of people stock dipping into the 8s.
Travis at Cobb has said that low 12's in DI engine is fine. I have been running high 11's and low 12's for some time. When you run too rich your fuel pump can't keep up. I'm running Stg2+SF91v105 FMIC with mods below and my fuel pressure is fine. I'm 11.8 to 12.35 AFR and the car hauls ass. Direct injection is more precise which means you can run leaner and direct injection has a cooling effect as well.
I would post the link to Travis's comments but this forum gets pissed when you direct people to sites that don't pay them money.
Darth Vader
Member
I understand DI. PI also has a cooling effect, like a chemical intercooler, from injecting a liquid heat sink upstream of the intake valve. DI allows for higher static compression ratios with higher boost levels but it doesn't obviate the need to keep combustion temps under control. It helps with that *slightly* better than PI but, it's no miracle cure.
If you can be totally sure that under every condition it never gets higher than low 12s, you'll be allright. Certainly that is, theoretically, about perfect for performance. However, I think leaving just a touch more headroom to account for unforeseen eventualities is pretty smart. I even do this on the cars I race and don't have to rely on daily.
If you can be totally sure that under every condition it never gets higher than low 12s, you'll be allright. Certainly that is, theoretically, about perfect for performance. However, I think leaving just a touch more headroom to account for unforeseen eventualities is pretty smart. I even do this on the cars I race and don't have to rely on daily.
sumthaiguy
Member
when i was intake/downpipe i went to a dyno day and i suction-cupped the dashhawk to the windshield so i could watch my AFR's while they did the runs. b**** dipped well into the 8's on all 3 runs.
Darth Vader
Member
That's diesel-rich, lol. Do that alot and you're in cat-melting territory.
Another thing to consider is that while your AVERAGE afr may be 12:1, indicated by your DH, the individual cylinders may be quite different. One hitting 13.5:1 and one 10:1 will average at around 12 but, one is on the way to melting down. You've got to leave a little room for flow variations between the cylinders.
I haven't flowed this manifold but, I'll give you an example from another platform. The factory lower intake on a 5.0 Ford's worst cylinder (#5) flows about 70% less than its best cylinder (#8). So, #5 was pretty much a dead hole given how much fuel was flowing through it without air, 8 was running a touch hot because of too much air. All's well for the ECM on the AFR at the downstream O2 sensors, though, at least as much as narrow band sensors could tell.
Another thing to consider is that while your AVERAGE afr may be 12:1, indicated by your DH, the individual cylinders may be quite different. One hitting 13.5:1 and one 10:1 will average at around 12 but, one is on the way to melting down. You've got to leave a little room for flow variations between the cylinders.
I haven't flowed this manifold but, I'll give you an example from another platform. The factory lower intake on a 5.0 Ford's worst cylinder (#5) flows about 70% less than its best cylinder (#8). So, #5 was pretty much a dead hole given how much fuel was flowing through it without air, 8 was running a touch hot because of too much air. All's well for the ECM on the AFR at the downstream O2 sensors, though, at least as much as narrow band sensors could tell.
sumthaiguy
Member
lol what cats? sounds good guys! i just talked to PTP and i should be placing an order this week. possibly tomorrow. i am currently running on defective carpe diem internals. havent pushed the car in like a year XD. itll be nice to regain the power ive lost.
possibly....................thats what I thought till I ran few more pulls around 5000..then i hit the cut...but ofcourse now at 500 miles afterwards..im golden..no cut whatsoever...pulls are very strong..will get some actrual data out when im not so dam busy 
...........ps... for my car it took about 250 miles to be completly broken in..all cars vary..good luck.
...........ps... for my car it took about 250 miles to be completly broken in..all cars vary..good luck.Darth Vader
Member
My internals did exactly what yours are doing at 100 miles and no trouble with WOT pulls. At full chat it maintains between 17-1800 psi all the way to redline....as opposed to dropping to 700 after 5000 like before.
Hey Biggs go ahead and open her up..only way really to find out is to do some wot pulls..Looks like my internals were just really stubborn and took thier sweet ass time to break in...But anyways You might be broken in. Im running my super low conservative 14 psi map right now..still pulls pretty dam hard..think im around 270 whp with the 14...which is plenty for winter daily driving..once spring hits ill put the 17 psi map back in
My PTP Pump took about 400miles but I pussed on the first 250. I did some 5-6k steady pulls in 2nd to break mine in. 5-6k then shift after 30s to 1m then slowdown shift down and repeat. After about 20m of this I went for a nice 150mile drive before I tried WOT again. When I did, Zoooooooom no issue.
Solid approach on the break-in Bravnik...I did the same till 100 miles then tried alittle wot in 2nd 3 rd gear..but hit cut around 4500-5000 rpm..didnt try again for another 100 miles..it was better..but piston was still "sticking"...yeah I hear ya...zoom zoom is now no prablem Just goes to show that these pumps have tight tolerances=good thing...and that you just got monitor your fuel psi and break in time will vary..but use common sence and dont even try wot till least 100..if not prabaly 2-300 miles. so far so good and im impressed with this Pt-performance product.
Just goes to show that these pumps have tight tolerances=good thing...and that you just got monitor your fuel psi and break in time will vary..but use common sence and dont even try wot till least 100..if not prabaly 2-300 miles. so far so good and im impressed with this Pt-performance product.
