3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

horsepower and torque

Thread Tools
 
Search this Thread
 
Old May 8, 2008 | 12:09 PM
  #1  
BlueShift's Avatar
Thread Starter
2JZ Sellout
 
Joined: Jan 2007
Posts: 416
Likes: 0
From: Renton
Question horsepower and torque

Ok, I am getting tired of guessing and re guessing my power and Torque. My bigest problem is that I do not have easy access to a DYNO, so without that all I can do is speculate. I have no idea where my car sits but I have a rough guess and I was hoping maybe someone with similar parts can help me out.

What is done:
Street port
'99 spec twins
E-fini Y-pipe (does this even do anything to help hp?)
3" down pipe
Factory main CAT (short term for emissions, otherwise 3" mid)
Racingbeat 3" single tip exhaust.

I think the car is somewhere in the 290-300 Shaft HP and I am not sure what the loss ratio is. Also, when I bought the car the previous owner said it had a '99 rear end, I am not sure if that changes matters either. I am just tired of people calling BS when I say I am over 280hp. When I know for a fact stock '99 had 276hp. I know that the only real way to prove anything is to do a dyno run but again it is hard for me to get to one. I am running a stock ECU but I plan to get a PFC as soon as I can afford one. At that point I am going to have it tuned and dyno'd but that could be as far as 6-months out. If anyone can give me at least an idea it would be nice.
Thanks for the Help!!
Reply
Old May 8, 2008 | 12:22 PM
  #2  
White94RX's Avatar
BMW Tech
Tenured Member 05 Years
 
Joined: Mar 2002
Posts: 845
Likes: 0
From: Auburn, Alabama
umm, you better go ahead and get a PFC, like yesterday.
Reply
Old May 8, 2008 | 12:41 PM
  #3  
Tom93R1's Avatar
gross polluter
Tenured Member: 25 Years
iTrader: (2)
 
Joined: Mar 2001
Posts: 1,757
Likes: 25
From: Chandler, AZ
No kidding! Dont even sit in the driver seat with the key in your hand until you get the powerFC unless you want to be buying a new motor right away. At the very least dont put that mid pipe back in! Probably should put your stock cat-back in as well.
Once you get the PowerFC in there and tuned you should be maxing out your stock fuel system around 300-320 at the wheels.
Reply
Old May 8, 2008 | 12:45 PM
  #4  
BlueShift's Avatar
Thread Starter
2JZ Sellout
 
Joined: Jan 2007
Posts: 416
Likes: 0
From: Renton
yeah, the idea is not to run the mid pipe until I get the PFC, the stock CAT is in for the time being.
Reply
Old May 8, 2008 | 02:03 PM
  #5  
Montego's Avatar
Don't worry be happy...
Tenured Member: 20 Years
Loved
Community Favorite
Top Answer: 1
iTrader: (1)
 
Joined: Apr 2001
Posts: 6,901
Likes: 842
From: San Diego, CA
come on you guys.. when it comes to the stock ECU it's all about boost levels not mods.


To the original poster: maintain 10 psi of boost(not 10.5 but 10 max!), no creep , no spikes and your car should be fine.

If you over boost: boom no question.
Reply
Old May 8, 2008 | 03:05 PM
  #6  
Upgrayedd's Avatar
Double Dose
Tenured Member 15 Years
iTrader: (1)
 
Joined: Dec 2005
Posts: 4,009
Likes: 1
From: Seattle
That was the problem with the midpipe in he was creeping to 16psi. His 99's are boosting near 12lbs according to his gauge, no telling how accurate it is... My gauge has been off as much as 1.5lbs at times. Usually pretty accurate however. Power numbers should be easily in the 290-300 range I would anticipate with the streetport and extra 2 psi of boost the 99's are appearing to provide over the stock turbos. Could be attributed to the dowpipe and catback tho.

Chris, you should've come to Apple Blossom and done dyno runs We need to organize a discounted dyno day for the NW guys for sure. I'd like to once I get my fuel system and tune done
Reply
Old May 8, 2008 | 04:31 PM
  #7  
Tom93R1's Avatar
gross polluter
Tenured Member: 25 Years
iTrader: (2)
 
Joined: Mar 2001
Posts: 1,757
Likes: 25
From: Chandler, AZ
Originally Posted by montego
come on you guys.. when it comes to the stock ECU it's all about boost levels not mods.


To the original poster: maintain 10 psi of boost(not 10.5 but 10 max!), no creep , no spikes and your car should be fine.

If you over boost: boom no question.

Not exactly. If you have a ported engine, freer flowing intake and exhaust then you have more air going through the motor even at stock boost levels. Fuel is not adjusted because the ECU still just sees 10psi, so now you have more air + same fuel = lean condition and recipe for disaster. It indeed is not just about maintaining the 10psi, its about maintaining the stock or close to stock air flow through the engine.
Reply
Old May 8, 2008 | 07:17 PM
  #8  
Montego's Avatar
Don't worry be happy...
Tenured Member: 20 Years
Loved
Community Favorite
Top Answer: 1
iTrader: (1)
 
Joined: Apr 2001
Posts: 6,901
Likes: 842
From: San Diego, CA
Originally Posted by Tom93R1
Not exactly. If you have a ported engine, freer flowing intake and exhaust then you have more air going through the motor even at stock boost levels. Fuel is not adjusted because the ECU still just sees 10psi, so now you have more air + same fuel = lean condition and recipe for disaster. It indeed is not just about maintaining the 10psi, its about maintaining the stock or close to stock air flow through the engine.

The stock ECU actually runs rich enough for all the boltons. This has been proven with wideband tests on the stock ECU. Wade proved this years ago as he tested various stock cars for A/F ratios. As it turned out the base map for the PFC is actually leaner that the stock ECU IIRC. Sorry I don’t have a link to all the data that was collected but it's out there. I've seen it but I can't find it right now. Maybe if Mahjik see this he can help us out.


I also speak from experience. I had a MILD STREETPORT, M2 CAI, PFS SMIC, DP, MP, ported turbos, all on the stock ECU. I ran around like that for about two to three years. WOT every chance I got but I maintained my boost to 10 psi max.
Reply
Old May 8, 2008 | 07:27 PM
  #9  
SLOASFK's Avatar
Top's always down
iTrader: (5)
 
Joined: Dec 2005
Posts: 4,841
Likes: 2
From: Spain
Originally Posted by montego
come on you guys.. when it comes to the stock ECU it's all about boost levels not mods.


To the original poster: maintain 10 psi of boost(not 10.5 but 10 max!), no creep , no spikes and your car should be fine.

If you over boost: boom no question.
Usually true, but porting advances the timing on the engine. As you probably know, timing is everything If the timing is off by enough, the plugs will ignite the A/F mixture before the apex seal is set resulting in the same effect as detonation.

Obviously this only applies to medium and large street ports, bports and pports. If the guy has a really small port, such as a Racing Beat port, then he shouldn't have a problem but he's still flirting with the line on an engine that has been known to be picky.
Reply
Old May 8, 2008 | 07:41 PM
  #10  
Rxmfn7's Avatar
Do a barrel roll!
Tenured Member 20 Years
iTrader: (4)
 
Joined: Oct 2001
Posts: 7,529
Likes: 2
From: Lower Burrell, PA
You have access to a drag strip? Get us a few runs with an average trap speed and you can guestimate HP pretty close.
Reply
Old May 8, 2008 | 07:50 PM
  #11  
zack4173's Avatar
Rotary Enthusiast
Tenured Member 10 Years
iTrader: (3)
 
Joined: Jan 2006
Posts: 1,020
Likes: 0
From: Bonney lake Washington
I have pretty close to the same as you and I got 280WHP last september at 12 PSI. I didnt have a midpipe though.
Reply
Old May 8, 2008 | 08:03 PM
  #12  
T2 Tsunami's Avatar
Stud Service
Tenured Member 15 Years
iTrader: (3)
 
Joined: Apr 2002
Posts: 741
Likes: 0
From: Lancaster PA
there are three things you need to keep things safe
FUEL COLD AIR(intercooler) ENGINE MANAGEMENT
you have none....youe asking for trouble
Reply
Old May 9, 2008 | 03:33 AM
  #13  
fendamonky's Avatar
F'n Newbie...
Tenured Member: 15 Years
Liked
Loved
Community Favorite
iTrader: (6)
 
Joined: Sep 2006
Posts: 3,942
Likes: 323
From: Nokesville, Va
^ I would say that boost control is more important than an aftermarket EMS.

I say this purely based off the fact that the stock ECU is perfectly fine for stock boost pressure. What's the best way to limp around a recently hooked up engine w/o blowing something, before a tune??

Granted.. opening up flow and trying to push an engine on the stock ECU is just asking for trouble...
Reply
Old May 9, 2008 | 04:30 AM
  #14  
SLOASFK's Avatar
Top's always down
iTrader: (5)
 
Joined: Dec 2005
Posts: 4,841
Likes: 2
From: Spain
Originally Posted by fendamonky
^ I would say that boost control is more important than an aftermarket EMS.
This is true for a stock ported engine...this guy has a street port.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
alfred1976
1st Gen General Discussion
6
Oct 1, 2017 09:51 PM
gabescanlon
V-8 Powered RX-7's
47
Mar 21, 2016 12:45 PM
RedBaronII
3rd Generation Specific (1993-2002)
4
Sep 20, 2015 11:29 AM
doritoloco
New Member RX-7 Technical
7
Sep 5, 2015 12:41 PM




All times are GMT -5. The time now is 07:21 PM.