[Dk]Rx7

hey guys,
My car is running funny now and I was just hoping you guys could help me out. Today I installed a resonated midpipe ( I have dp, mp, cb, greddy pulleys, intake, and Power FC btw) and my friend asked me if I wanted to race (new M3). Of course I couldn't back down so i said yes. We raced at a 40mph roll and when my rpms went to 6k it bucked and bucked again at 7k and that happened through every gear during the race. It felt very uncomforting and after the race, my car idles very bad, and the vacuum is like at 12hg/800rpm (also shakes bad). I checked my power FC (running base maps) and i peak boosted at 0.94 bar (about 13.8 psi) which was very frightening. My car sounds fine when you rev it and such, but it idles very bad and the vacuum is low. I drove it and it was boosting fine. When I was racing I thought I popped a motor cause the car felt funny. Sorry for this long post but I had to give a background of what happend. Any suggestions would help. Thanks and hope to hear from you guys soon.

maxcooper

That doesn't sound too good, Dk. I suggest getting a compression test.

-Max

[Dk]Rx7

=( hopefully its not a blown motor, but if it is should I consider buying a large street ported (5 year waranty) pineaple racing motor and pay for installation? Also, what else do I need done when I get a new engine in? I dont want to miss anything and regret not putting something in or replacing it. Thanks in advance for all the inputs and suggestions.

skunks

the warrenty does not really cover the boost stuff, they say if you over boost the engine/run lean or what ever (which is the only thing that will kill a rotary!), they will not warrenty it.

Pineapple racing is one of the best places you can get your engine rebuilt though (actually, I think it is the best place because its the only place where I have heard good stuff from, not one person I have heard from yet has complained about them which says a lot!!!) and if I needed a rebuild, I'd send my engine there!

BTW: You gotta be kidding me, some one just challenges you to a race and you actually race your untuned FD??? wtf are you thinking dude? Unless you got tons of money and can afford new engines at a drop of a hat, that was a really foolish move!

Shinobi-X

The first question I asked myself when I saw your post, was if the car is tuned propely?

wonder1and

Do you have a warranty?

es

And this is why everbody thinks rotaries are "weak"...

DK, midpipes are no joke, & you'd be damn lucky to have control over your boost even if the PFC were tuned. when I had all of the mods you listed I couldn't keep boost below 14PSI (Profec B) on a hot day & short shifting at 7K. I had the boost cut set to 1.1 though & have 1300cc secondary injectors (no fuel cut or injector saturation).

Things you should seriously consider doing now:
Clutch
Plug wires
Engine harness if mileage is ~100K'
New turbos (because that broken apex seal bit probaby chipped a turbine)
Port wastegate (so this wont happen again)
Coolant hoses
Vacc hoses
Injector cleaning and or porting
New Fuel pulsation dampner
New oil injector tubes if mileage is ~100?K
& there's probably more but I'm a zombie today...

dubulup

Sounds blown to me too.

Nameless

I agree... sounds really bad. Compression test is in order. Good luck though.

I got my engine done at Pineapple, I'd reccomend them to everyone.
Next time, when you get the engine in, break it in... then drive on over to XS and get it tuned before mashing the pedal.

[Dk]Rx7

Yea, racing him was probably pretty foolish, but I was ready to get a new engine soon anyways. I didnt realize that the powerfc couldn't control the boost that well. Maybe it will all work out in the end, because I had a coolant seal problem, and I was just going to drive my car until it really gave out. I guess this is a sign to move forward and get a new engine + turbo. I'll be sure to take it easy with my new engine, and take all the preventive measures. THanks for all the input guys, it really helped.

Mahjik

iTrader: (1)

It's not that the PFC can't control boost that well... If what you experienced was boost creep (which is probably what it was), then no boost controller can help you out. The wastegate is already at 100%, there is nothing else it can do (therefore, that renders boost controllers almost useless in that situation).

I'm not trying to slam you, but it doesn't seem like you did too much research before adding the mods to your car. Take es's advice above and use this opprotunity to learn from what happened so it doesn't happen again.

I'm hoping you really didn't blow a seal, but it sounds like it.

Good luck.

matty

ya know with his mods and the power fc his car should be pretty close to dead on tuned! Except he may be alittle lean around 2500-3000rpms. He said he detonated at 6k and 7k rpms not down low.
I have same mods and had a 11.4 afr. We just added fuel down low.

Mahjik

iTrader: (1)

Actually, the base map of the PFC is leaner than the stock ECU (according to others' findings). If that is true, then anything over stock boost on an untuned PFC is asking for trouble.

matty

i have heard/read that too...but my experiece is above...full exhaust, intake and power fc equalled 11.4 afr @ 12 psi. Only lean area was 2500rpms-3000 rpms

[Dk]Rx7

the thing is, i did do some research and i've read people with my same mods and they've been running fine with base maps. If the midpipe boosts creep like that, and the wastegate is %100 then how am I suppose to cure/solve the problem? =( Thanks for all the suggestions, and yea this is probably going to be an expensive lesson.

Mahjik

iTrader: (1)

Porting the wastegate or adding restriction to the exhaust (i.e. restriction plates or using a hi-flo cat).

Mahjik

iTrader: (1)

Well, I think this is a good example of why not to use the base map. IMO, you should never use the base map, you should have it tuned to your car. I think it's a waste of money to buy a programmable ECU and not tune it (as well as dangerous to your engine).

But, each car is different so I wouldn't count on every car reacting the same way to the same PFC map (even with similar mods).

es

Dk, boost creep is cured by porting the wastegate as I mentioned before. If you decide to upgrade to a single turbo then you wont have any creep problems since the wastegate is also replaced.

The XS T04E kit is a very good kit for the price. It can support ~400RWHP & the turbo is easily rebuilt. You might want to consider that as an option.

Matty, I'm thinking the stumbling was more along the lines of overboost fuel cut then a simple lean condition induced detonation. If that's the case (which is what is sounds like to me) then I don't care how rich you're A/F is. Keep on the pedal to redline through all the gears & your going to spit chunks!

My opinion.
Eric.

matty

i hear ya...the reason i didnt think fuel cut is b/c .94 boost would mean his secondary would have to have been set to .69 as measured by the pfc...that isnt the stock setting...atleast it wasnt on mine.