starscream5000 said:
GT40 and a GT40r is the same turbo. Only difference is the ball bearing option with is what the little "r" means.
If he's running 1kcc injectors with a single walbro.. he'll starve that walbro. likely already is.
Trouble with boost over 1bar
- Thread starter topgear
- Start date
GT40 and a GT40r is the same turbo. Only difference is the ball bearing option with is what the little "r" means.
If he's running 1kcc injectors with a single walbro.. he'll starve that walbro. likely already is.
aljordan said:
Garrett GT40 compressor map: http://s4wiki.com/wiki/Image:GT40compress.jpg
Carrett GT40r compressor map: http://s4wiki.com/wiki/Image:GT40rcompress.gif
These are the two compressor maps I was looking at when I made the comment on them.
starscream5000 said:
Different trims.
Looking at the garrett site shows a gt4088r wheel at 63.5/88 (inducer/exducer). It also shows a gt4088 at 64.7/88. Different wheels for the same turbo. Weird.
http://www.turbobygarrett.com/turbobygarrett/tech_center/gt_basics.html
topgear said:
your car sounds like what mine did when I first got it running. You are going BIG PIG RICH @ high RPM, motor is going to fall flat on its face around 4500RPM.
Even with me running 580's and taking 30% of the fuel out I was rich, but not so rich it was falling flat. You need smaller injectors and a good tune. You are barking up the wrong tree ("looking in the wrong area") in trying to get more spark, forget about the ignition for now, take some fuel out.
theWeezL said:
Good points throughout, hard to tell a tune without a wideband, or atleast EGT's... Go back to the dyno and pay for them to tune it for you. That may be your best luck.
Joining here late... certainly not claiming any superior knowledge on this...
...but...
I don't think your system is ANYTHING near efficient with the combination and problem description you are giving... and I FURTHER agree with the opinions that you are "falling on your face" (term meaning = vehicle "loads up" and loses power...).
1000cc injectors????? WHY!? (for 400HP ranges, anyway...)
I am a "lowly" 440cc setup, but able to push 16psi very HARD... and I had to "back off" the GAIN on my VPC to keep from "LOADING UP" my fuel. (I can BOOST to HIGHER levels... but I believe I'll be 100% cycling my injectors... a recipe for LEAN DISASTER!) My car is pretty efficient, as I am ABLE to obtain around 28MPG if I use BOOST very modestly for a highway cruise... (even boosting alot... I achieve better than 20 no problem.)
I think your "fuel dump" into the cylinders is "overwhelming" the motors ability to burn a cleanly atomized mixture... check a plug. (Mine burn a tan color... and I blow very little "boost fart black smoke" when I "hit it"... a good sign, me thinks.)
Can you DIAL DOWN your fuel delivery (GAIN) as it comes on the boost? (and if the plugs are "fouled"... black or wet, even... I'd put a fresh set of quality... NGK, Denso and the like... although personally, I like the Silverstone Beru plugs.)
Good luck, man.
-crisp
...but...
I don't think your system is ANYTHING near efficient with the combination and problem description you are giving... and I FURTHER agree with the opinions that you are "falling on your face" (term meaning = vehicle "loads up" and loses power...).
1000cc injectors????? WHY!? (for 400HP ranges, anyway...)
I am a "lowly" 440cc setup, but able to push 16psi very HARD... and I had to "back off" the GAIN on my VPC to keep from "LOADING UP" my fuel. (I can BOOST to HIGHER levels... but I believe I'll be 100% cycling my injectors... a recipe for LEAN DISASTER!) My car is pretty efficient, as I am ABLE to obtain around 28MPG if I use BOOST very modestly for a highway cruise... (even boosting alot... I achieve better than 20 no problem.)
I think your "fuel dump" into the cylinders is "overwhelming" the motors ability to burn a cleanly atomized mixture... check a plug. (Mine burn a tan color... and I blow very little "boost fart black smoke" when I "hit it"... a good sign, me thinks.)
Can you DIAL DOWN your fuel delivery (GAIN) as it comes on the boost? (and if the plugs are "fouled"... black or wet, even... I'd put a fresh set of quality... NGK, Denso and the like... although personally, I like the Silverstone Beru plugs.)
Good luck, man.
-crisp
.6mm is .0236 gap which is entirely too small. Where did you get that spec? I would run .28 at the min and maybe more like .3 (stock spec is .32 if Im not mistaken)
and picking up others thoughts here on SM I have never heard anyone say they like Bosch Plats in a performance turbo application.
But again, I dont think ANY plug is gonna fire off that much fuel.
and picking up others thoughts here on SM I have never heard anyone say they like Bosch Plats in a performance turbo application.
But again, I dont think ANY plug is gonna fire off that much fuel.
jetjock said:
Perhaps I have misunderstood the relationship between thermal conductivity and resistance... (among OTHER things...)
My bad.
Here is the "Nology" literature that I have several times reflected upon... but of course, they are selling their product, too.
^^^ Don't know if that will be "legible"...
Sorry, back to topic...
-crisp
Well, they're certainly right about one thing: spark plugs are the subject of much controversy, along with other "high performance" ignition products. Right up there with oil. It's why I very seldom get involved in threads about them. Electrode resistance is probably close to the bottom of factors effecting plug performance. Rather than trust a maker's literature I suggest some study on secondary waveform analysis, followed by some on plasma physics.
You're welcome. Didn't mean to come across as Jargon the Magnificent, I'm just a stickler for proper terms. Since any electrical arc is comprised of plasma it helps to understand the physics behind the stuff. Ionization, etc. It is after all the most common form of "matter" in the universe. Learning about secondary waveform analysis will provide an understanding of what goes on in the ignition system and plug gap during a firing event. It can be used to literally see which plug works best in a given application.
topgear
Man, I'm almost sure, your trouble is in CPS readings. I've installed Haltech E8 recently and have same trouble too. In some RPM range your standalone (and mine too) can't read cam position teeth. That causes wrong RPM readings. But the worst thing, that it causes wrong map point. So, if you watch your timing with timing light, it will jump like crazy when you hit your trouble RPMs.
I don't know how to fix it yet. May be I will convert 24+1 wheel to 12+1 wheel... May be try to change air gaps in VR sensors... But I'm not trying to tune ANY boost while my timing jumps... And you have tried high boost with WRONG timing... That caused BHG.
PS: many people are very smart here... but now they tell nonsence. Your 1000cc injectors are big, yes. You can't get good AFR's at idle (more than 12 I think)... But they should run ok in boost area... So, I bet it is CPS reading problem. Period.
Man, I'm almost sure, your trouble is in CPS readings. I've installed Haltech E8 recently and have same trouble too. In some RPM range your standalone (and mine too) can't read cam position teeth. That causes wrong RPM readings. But the worst thing, that it causes wrong map point. So, if you watch your timing with timing light, it will jump like crazy when you hit your trouble RPMs.
I don't know how to fix it yet. May be I will convert 24+1 wheel to 12+1 wheel... May be try to change air gaps in VR sensors... But I'm not trying to tune ANY boost while my timing jumps... And you have tried high boost with WRONG timing... That caused BHG.
PS: many people are very smart here... but now they tell nonsence. Your 1000cc injectors are big, yes. You can't get good AFR's at idle (more than 12 I think)... But they should run ok in boost area... So, I bet it is CPS reading problem. Period.