Single Turbo RX-7's Questions about all aspects of single turbo setups.

Embarrassing night at the track. Missing a ton of HP. Ideas?

Thread Tools
 
Search this Thread
 
Old 03-31-10, 01:08 PM
  #26  
4th string e-armchair QB

iTrader: (11)
 
Trots*88TII-AE*'s Avatar
 
Join Date: May 2005
Location: North Bay, Ontario
Posts: 2,745
Likes: 0
Received 0 Likes on 0 Posts
Yeah definitely. Try a set of the NGK R6725 10.5's all around. They aren't cheap, but if you're gonna be cranking it up over 500whp, they'll do the job and last, you won't have to worry about them.
Old 03-31-10, 01:41 PM
  #27  
Movie Star

iTrader: (11)
 
Gohan3rdrift's Avatar
 
Join Date: Dec 2003
Location: Fort Wayne, Indiana
Posts: 982
Likes: 0
Received 0 Likes on 0 Posts
Is there a wideband on the car?
My first instinct is to check the A/F.

And also, you suck at driving.
How do you expect to holeshot with those 100spoke daytons?



ninja edit:
Also, use youtube so quality doesn't suck *****.
Old 03-31-10, 02:00 PM
  #28  
Rear Admiral

iTrader: (3)
 
CowsniperRX7's Avatar
 
Join Date: Jul 2002
Location: St. Louis, MO
Posts: 1,685
Likes: 0
Received 0 Likes on 0 Posts
Gohan tells it like it is son!
Old 03-31-10, 03:49 PM
  #29  
Rotary Freak

iTrader: (8)
 
rx72c's Avatar
 
Join Date: Jun 2003
Location: Australia
Posts: 2,800
Received 115 Likes on 65 Posts
I reckon the car never made 400+rwhp on 15psi to begin with.

Thats just my guess. Seen it to many times.

People come in with huge dyno sheets, put it on my dyno and make up to 150rwhp less with no changes.

Just cause steve kan uses someone elses dyno dosnt stop you from strapping the car down loosely or playing with atmospheric conditions on the dyno or sticking the air temp sensor on the exhaust housing. Ive seen alot of dodge tricks from my early times in working other workshops.
Old 03-31-10, 05:12 PM
  #30  
*** Bless The USA

Thread Starter
iTrader: (8)
 
Viking War Hammer's Avatar
 
Join Date: Jan 2007
Location: Saint Louis / Illinois
Posts: 7,139
Received 0 Likes on 0 Posts
Originally Posted by rx72c
I reckon the car never made 400+rwhp on 15psi to begin with.

Thats just my guess. Seen it to many times.

People come in with huge dyno sheets, put it on my dyno and make up to 150rwhp less with no changes.

Just cause steve kan uses someone elses dyno dosnt stop you from strapping the car down loosely or playing with atmospheric conditions on the dyno or sticking the air temp sensor on the exhaust housing. Ive seen alot of dodge tricks from my early times in working other workshops.
It went 11.50's @ 121 mph @ 15psi after Steve Tuned it. During the same day/tune, my previous FD put down 603whp and went 10.03 on the brakes.

I'm not sure what kind of operation you Aussi folks run, but Steve Kan aint like that.
Old 03-31-10, 06:53 PM
  #31  
Rotary Freak

iTrader: (12)
 
moehler's Avatar
 
Join Date: Mar 2003
Location: South Jersey
Posts: 2,319
Received 32 Likes on 27 Posts
My car made boost fine at 17 psi, I dyno'd it only because I was at a friends shop with a Dynopack (sp?).... it was missing 100 rwhp! Turned out the coupler on the compressor housing was loose. We tightend it and the car made 100 more rwhp on the 2nd pull. I didn't even notice it was loose since I was making good boost, who knows how long I was driving like that.

I would def check for a boost leak...
Old 03-31-10, 07:01 PM
  #32  
IRS Champion

 
enzo250's Avatar
 
Join Date: Aug 2001
Location: NY
Posts: 2,038
Likes: 0
Received 1 Like on 1 Post
Definitely have a look at all the piping.. 111mph is not alot of hp definitely not 450hp..
Old 03-31-10, 07:04 PM
  #33  
Rotor Head Extreme

iTrader: (8)
 
t-von's Avatar
 
Join Date: Apr 2002
Location: Midland Texas
Posts: 6,719
Likes: 0
Received 26 Likes on 17 Posts
Slipping differential will cause all kinds of hp losses. Any way to check that out?
Old 03-31-10, 07:21 PM
  #34  
*** Bless The USA

Thread Starter
iTrader: (8)
 
Viking War Hammer's Avatar
 
Join Date: Jan 2007
Location: Saint Louis / Illinois
Posts: 7,139
Received 0 Likes on 0 Posts
Originally Posted by t-von
Slipping differential will cause all kinds of hp losses. Any way to check that out?
It's a KAAZ and it's tight as hell.
Old 03-31-10, 07:34 PM
  #35  
Rear Admiral

iTrader: (3)
 
CowsniperRX7's Avatar
 
Join Date: Jul 2002
Location: St. Louis, MO
Posts: 1,685
Likes: 0
Received 0 Likes on 0 Posts
wtf
Old 03-31-10, 08:14 PM
  #36  
Movie Star

iTrader: (11)
 
Gohan3rdrift's Avatar
 
Join Date: Dec 2003
Location: Fort Wayne, Indiana
Posts: 982
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Viking War Hammer
It went 11.50's @ 121 mph @ 15psi after Steve Tuned it. During the same day/tune, my previous FD put down 603whp and went 10.03 on the brakes.

I'm not sure what kind of operation you Aussi folks run, but Steve Kan aint like that.
Old 03-31-10, 08:35 PM
  #37  
_________________________

iTrader: (3)
 
zinx's Avatar
 
Join Date: Jul 2002
Location: Indianapolis
Posts: 1,723
Likes: 0
Received 1 Like on 1 Post
I doubt there is anything you can it. Its a goner. I'll take it off your hands so you don't have to deal with it.


Seriously though, i'd do what others have said. Pressure test the intake first. I found all sorts of little leaks when i did this. Since you're loosing that much power it will be obvious.

Second, make sure all the plugs are firing. If the leading coil is out, it will probably still run and drive fine (depending on the tune), but you will be way down on power.
Old 03-31-10, 08:41 PM
  #38  
*** Bless The USA

Thread Starter
iTrader: (8)
 
Viking War Hammer's Avatar
 
Join Date: Jan 2007
Location: Saint Louis / Illinois
Posts: 7,139
Received 0 Likes on 0 Posts
So, when pressure testing it; if I'm pressuring one side of the engine, don't I need to plug up the other side?
Old 03-31-10, 08:45 PM
  #39  
Lives on the Forum

iTrader: (8)
 
thewird's Avatar
 
Join Date: Oct 2006
Location: Toronto, Canada
Posts: 6,591
Likes: 0
Received 11 Likes on 11 Posts
No, unless your e-shaft is positioned in a way that the intake and exhaust is open. Just turn it manually or crank the car to turn it and try again.

thewird
Old 03-31-10, 09:01 PM
  #40  
*** Bless The USA

Thread Starter
iTrader: (8)
 
Viking War Hammer's Avatar
 
Join Date: Jan 2007
Location: Saint Louis / Illinois
Posts: 7,139
Received 0 Likes on 0 Posts
Right on, thanks.
Old 03-31-10, 09:05 PM
  #41  
*** Bless The USA

Thread Starter
iTrader: (8)
 
Viking War Hammer's Avatar
 
Join Date: Jan 2007
Location: Saint Louis / Illinois
Posts: 7,139
Received 0 Likes on 0 Posts
Originally Posted by Gohan3rdrift
How do you expect to holeshot with those 100spoke daytons?
Yo son, you got me
Old 03-31-10, 09:48 PM
  #42  
Turbo widebody FB

iTrader: (1)
 
Dan_s_young's Avatar
 
Join Date: May 2004
Location: Alberta Canada
Posts: 3,733
Likes: 0
Received 2 Likes on 2 Posts
Another suggestion, alot of mechanic shops will have smoke testers for evaporative emissions systems. These can also work excellently for looking for intake leaks, they show very very small leaks quite quickly.
Old 04-01-10, 01:16 AM
  #43  
Rotary Freak

iTrader: (8)
 
rx72c's Avatar
 
Join Date: Jun 2003
Location: Australia
Posts: 2,800
Received 115 Likes on 65 Posts
Well 121mph is certainly not 450rwhp either so sorry to rain on your parade on that one.

more like 360-370rwhp.

So i guess you had a majic 90rwhp.

I would simply change your spark plugs and go back to have it retuned.
Old 04-01-10, 01:55 AM
  #44  
7s before paint!!!

iTrader: (2)
 
13B-RX3's Avatar
 
Join Date: Aug 2003
Location: Philly/Texas
Posts: 3,814
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Viking War Hammer
ceramic rotors


There is your problem right there
Old 04-01-10, 07:39 AM
  #45  
*** Bless The USA

Thread Starter
iTrader: (8)
 
Viking War Hammer's Avatar
 
Join Date: Jan 2007
Location: Saint Louis / Illinois
Posts: 7,139
Received 0 Likes on 0 Posts
Originally Posted by rx72c
Well 121mph is certainly not 450rwhp either so sorry to rain on your parade on that one.

more like 360-370rwhp.

So i guess you had a majic 90rwhp.

I would simply change your spark plugs and go back to have it retuned.
I never said 450 whp, I said 435 whp.

That's not the point, it's down on power; that's the point.

I think I'll go ahead and take everyone's advice accept yours.
Old 04-02-10, 10:58 PM
  #46  
Rotary Freak

iTrader: (8)
 
rx72c's Avatar
 
Join Date: Jun 2003
Location: Australia
Posts: 2,800
Received 115 Likes on 65 Posts
ok then mate. ill keep that in mind.
Old 04-03-10, 07:11 AM
  #47  
Living life 9 seconds at a time

iTrader: (2)
 
ErnieT's Avatar
 
Join Date: Feb 2001
Location: Abingdon, Md
Posts: 6,541
Likes: 0
Received 0 Likes on 0 Posts
Eric,
I agree, check for leaks, but a couple other things. Steve usually tunes very rich to be on the safe side. Nothing wrong with that, but it will foul plugs very quick. Also, you may not want to hear this, but do a compression check. If you have a catch can, check it for blow by.
Good luck bro and good to see your back.
Old 04-03-10, 08:43 AM
  #48  
Racing Rotary Since 1983

iTrader: (6)
 
Howard Coleman's Avatar
 
Join Date: Oct 2001
Location: Hiawassee, Georgia
Posts: 6,097
Received 520 Likes on 290 Posts
lots of good advice here and it will be interesting to learn what the problem is.

since you are missing a ton of hp and your motor appears to be running fairly well i would check for boost leaks on the primary side first. generally when you are down 50+ ponies you can hear the leak but i still rate it number one.

i would do a plug check second. you should pick up a bad coil from a plug check. generally, however, you are going to pick up a miss if your ignition is crapping out due to plug wires, a coil or just a fouled plug.

AFRs could be the problem as the motor would run o k but could easily be down 50 hp+ due to an overly rich AFR.

a dirty airfilter would also be something to check.

how about the emergency brake?

keep us posted as we are all curious as to where the ponies are hiding.

hc
Old 04-03-10, 01:05 PM
  #49  
Please somebody help!!!

iTrader: (1)
 
NissanConvert's Avatar
 
Join Date: Sep 2005
Location: Woodridge, IL
Posts: 1,442
Likes: 0
Received 0 Likes on 0 Posts
I ran 13.7 at 98 pedaling boost on poor man's nonsequential twins- stock everything except exhaust.

Something is seriously amiss with your car.
Old 04-05-10, 10:48 PM
  #50  
Full Member

 
RotaryRX-007's Avatar
 
Join Date: Apr 2008
Location: Melbourne Beach, FL
Posts: 169
Likes: 0
Received 1 Like on 1 Post
I guess it didn't run that strong, eh?


Any luck yet?

Change plugs n' wires. Check boost leaks. Don't know if there is a way to test or check the msd unit to make sure it's firing at 100%? I am pretty sure that they are reliable but it's one more thing that could be the culprit.

Like previously mentioned, do the easy and cheap **** first. Then get dirty if it still eff's up.


Quick Reply: Embarrassing night at the track. Missing a ton of HP. Ideas?



All times are GMT -5. The time now is 11:00 AM.