13G vs. 13C Turbos

[keithmac]

I should be getting my back 13g fitted soon and will be doing some 1/4 mile runs later in the season, will see how the traps look. At the moment my best trap is a 110 with a 13gfront and 9b rear, but I`m still getting the hang of it.

[moffman93']

I would never spend any money on a turbo that came stock in some parts of the world(13g) . IMO, 13t/15g should be the MINIMUM upgraded turbo option. Spool is almost identical to 13g's but with ALOT more power potential.

[cbehnken]

one thing you guys aren't considering is the larger turbos are going to be opening the wastegate sooner and more often than the smaller ones.

This means not as much exhaust has to go through the turbine, so you should see gains just from that.

What do you think is going to make more power? A turbo that is in the higher parts of its efficiency running 85-90% of the exhaust through the turbine or a turbo running in the middle of its efficiency running only 60-70% of its exhaust through the turbine?

[Kibwe Walker]

Originally Posted by SkortchGT

I'll have that number for ya the next time I get on the dyno.

Link the resuls back to this thread if you can.

[3Sfever]

Originally Posted by Kibwe Walker

What I am driving at here though is a simple bolt on setup. I can't find ANY dynos, time slips (ET. or TRAP), that show a 13g car with simple bolt ons making what 13t's and 15g's do even at lower boost levels where they are suppose to be equivalent.

You are right, if there are any 13G numbers out there, they are hard to find.

BJMSAM, you need to get to the track, so we can end all the speculation.

Originally Posted by Kibwe Walker

I just want 1 objective number showing a 4xx AWHP from anywhere on the planet on a stock engine, stock cams, bolt on 13g's, FP, inj's, intake, and exhaust because thats all it takes for 13t's and 15g's to get over 400 to the wheels and thats all it takes to see 116+ traps.

The HP calculator quoted earlier in the thread, and very similar ones on Stealth316.com show approx 500hp crank hp to run 116mph traps,
so are we saying 116mph traps = approx 400 "wheel" hp? . . . Sounds reasonable . . . just confirming that 116 is the "goal" for a full weight 3S to be able to claim 400awhp.

Also to confirm, 13t/15g can easily make 400whp at 17psi on pump? (with the mods listed above) . . . Sorry, it has probably already been said numerous times, I am just too tired to go back and read again.

My interest in this is that I have some TD04L-13G's waiting to go on mine. I have the 120K on engine almost finished, but still need to go thru the tranny, and lots of little things to do. . . . I need to get moving, only 53 days to NG'08!!!

[Kibwe Walker]

Yes 456

[bjmsam]

Originally Posted by moffman93'

I would never spend any money on a turbo that came stock in some parts of the world(13g) .

I would never spend any money on a turbo that I didn't research and attempt to understand enough to determine whether it is appropriate for my needs. The 13Gs that came stock on European 3000GTs had the smaller TD04 turbine. Incidentally, I wonder if there is any truth to this statement (again, with the TD04 turbine): "The only 3000gt that ever had an 11g is a GTO MR in JAPAN."

Originally Posted by moffman93'

more power potential

There is no question that a larger compressor has more power potential when running outside of the parameters clearly stated in this thread.

Originally Posted by cbehnken

one thing you guys aren't considering is the larger turbos are going to be opening the wastegate sooner and more often than the smaller ones.

Interesting. Please elaborate!

Originally Posted by cbehnken

What do you think is going to make more power? A turbo that is in the higher parts of its efficiency running 85-90% of the exhaust through the turbine or a turbo running in the middle of its efficiency running only 60-70% of its exhaust through the turbine?

Where are you getting those numbers? As pointed out earlier in this thread, the 13G compressor is more efficient than the 15G compressor up through 6000 RPM where peak horsepower is typically generated.

Originally Posted by 3Sfever

You are right, if there are any 13G numbers out there, they are hard to find.

Not to mention turbine ambiguity.

Originally Posted by 3Sfever

BJMSAM, you need to get to the track, so we can end all the speculation.

I plan to as soon as I resolve my problems with spark blowout (new wires on the way, and if they don't work, I'll replace the coil pack). Perhaps I'll do a few G-Tech runs anyway. I have the first-gen model, and I had it running when I went to the track (with 9Bs and stock fuel); the ETs matched my timeslips exactly but the speed was slightly high since it measures terminal vs. trap. The newer ones estimate trap, so conversion may be possible.

Originally Posted by keithmac

I should be getting my back 13g fitted soon and will be doing some 1/4 mile runs later in the season, will see how the traps look. At the moment my best trap is a 110 with a 13gfront and 9b rear, but I`m still getting the hang of it.

With boost limited to what?

Originally Posted by 3Sfever

The HP calculator quoted earlier in the thread, and very similar ones on Stealth316.com show approx 500hp crank hp to run 116mph traps, so are we saying 116mph traps = approx 400 "wheel" hp?

The parasitic loss for my car was measured as 112 bhp (or 30%) during my 1999 dyno session.

Originally Posted by 3Sfever

Also to confirm, 13t/15g can easily make 400whp at 17psi on pump? (with the mods listed above) . . .

Depends on the dyno!

Originally Posted by 3Sfever

My interest in this is that I have some TD04L-13G's waiting to go on mine.

Mine feel terrific. The only way I might regret my decision is if I change my goals and want to raise boost on race gas (pump gas costs $9 per gallon over here, so not likely). Even then, I'm sure boost falling to 17-18 psi at redline would feel pretty good; Jack did nothing special to hit those 118-119 mph traps with TD04L-13Gs more than a decade ago.

[Kibwe Walker]

Originally Posted by bjmsam

Jack did nothing special to hit those 118-119 mph traps with TD04L-13Gs more than a decade ago.

Jacks numbers are special because they are the best ever with both 15g's and 13g's and its not a marginal difference, ITS A FREAKING HUGE DIFFERENCE between Jacks times and others with a similiar setup. Not even just Jack, throw in Ray Pampena, and Matt Monet into the mix aswell.

IF someone were to get 15g's I wouldn't be telling them to expect low 11's, I would tell them low 12's to high 11's is well within reason because thats where the majority seem to land with minimal mods.

Jacks entire letter.

----- Original Message -----
From: "xwing"
To: stealth-3000gt@list.sirius.com
Sent: Tuesday, October 26, 1999 12:35 AM
Subject: 9B, 13G, 15G relative performances

The 13G make at least 50+ hp more than the 9B. I did no other changes on my '93 and went from 12.727 @ 107.562 mph to 12.172 @ 112.890 mph quartermile on 8/31/94 going from 9B to 13G. This is somewhat over 50hp, and I did not have the VPC/550 injectors yet, so had to limit boost to ~16-17psi or fuelcut came in. In this configuration, went best of 114.350 mph on 9/27/94, ~65hp more (all stats are NO nitrous in this letter, except as noted).

--I think 9B's can be good for about 410hp at wheels maxxed out with standard stuff.

Once VPC/550 injectors in, 13G's went 12.000 and 119.381 best mph, on 4/8/95; about 500 hp at the wheels; overall, gained about 110 hp with 13G over 9B, but given other changes 13G likely ~100 hp better than 9B. 13G best ET was 11.702 @ 118.061 on 6/6/96; this was through traps in 3rd gear, on the rev limiter. I was the first 3000GT in the 11's 5/17/95 with an 11.937@118.338. --I think 13G can be good for about 510hp at wheels maxxed out with standard stuff.

15G best MPH was 11.387 @ 125.76 11/28/96 at the 1st Annual 3000GT/Stealth vs. Diamond Star Shootout in Temple, TX with the 550 injectors; about 575 hp at the wheels, so 15G make about 75 hp more than 13 G, but note I made some other changes so 15G likely ~40-50hp better than 13G. After that, 720cc injectors did not add any mph to trapspeed, indeed seemed to LOWER speed likely due to over-rich condition-- but lowered EGT a tad (max 1850 F at Temple) which may or may not have been good because knock could at random times mean EGT high due to retard, or due to a true lean mix. Best ET for me with 15G was 11.303 @ 122.54 at DSM Shootout 5/16/97, which I won class in full interior, as required by Dave Buschur...Adam Weltz went ~11.25 "no NOS".

--I think 15G can be good for about 580hp at wheels maxxed out with standard stuff.

My car made best 575 or so at wheels no NOS, but that is not "maxxed" because I always had stock intercoolers, no headers, no head/intake/throttlebody porting/ignition/standalone computer--with THOSE parts, my "maxxed out" figures could be somewhat higher...

Best 3000GT/Stealth ET/MPH overall is still my 10.810 @ 128.44 with 15G's, 50hp NOS on 6/3/97; I had the distinct honor of making this pass lined up with the late Jeff Curtis in his Stealth...

I'd not hesitate to get 13G's if desired and price right. The 15G make more topend, and I think they are worth it. 17G and more exotic turbos have yet to put better numbers to the pavement. When they do, we'll see what other mods/weight reductions etc are on the cars doing it. 15G are still unbeaten, both on motor and with NOS; are capable of 125 mph quartermile / 575+ hp AT THE WHEELS no NOS in my car, with only piggyback computer mods/no porting/enginework beyond the boltons. Pretty amazing, really.

Jack Tertadian
Atomic Motorsports

He even had the stock exhaust and DP. Now thats freaking insane, this guy is a man among boys because I couldn't pull that off and I am pretty good. Interesting note is that what boost was being run for those passes was not mentioned. One things for sure, I would make a safe bet that those best traps were not at 17 psi in either the 13g or 15g case.

[bjmsam]

Originally Posted by Kibwe Walker

Interesting note is that what boost was being run for those passes was not mentioned. One things for sure, I would make a safe bet that those best traps were not at 17 psi in either the 13g or 15g case.

Of course not, hence the context in which I mentioned his results.

Originally Posted by Kibwe Walker

He even had the stock exhaust and DP.

Exactly my point. Here's another of his posts, in which he reveals a "secret:"

Originally Posted by xwing

Re: Did 15G's ever trap 126mph?

The old days yes when everything was pretty much stock except a few boltons and (now crappy) HKS VPC for fuel control. I remember 1994 when HKS California importer had ceased selling VPC's for 3S. Robert O'Toole was there I think, telling me he would NOT sell me a VPC for the 3S unless I agreed NOT to try returning it WHEN it didn't work properly on my car. I agreed because it was the only way and I thought I knew how to fix it to work...well that opened up the car bigtime and let me FINALLY get past the devastating ~16psi fuelcut which had basically put an absolute HP limit on our cars up to then. Now, fuelcut as a problem? LOL we have many computers and piggybacks to get past THAT old stuff!

The 15G's I had were a little special in that they had a slightly larger turbine wheel, in the slightly bored-out TD04-13G turbine housing. That was a secret then

The problem I was having was that the small td04 centersections just were NOT built for nor up to the task of holding higher boost (24+psi, up to 28+ on spikes and with NOS) and the thrust bearings would wear, the turbos would start to leak oil and huff smoke out back as the wear got bad. So, I wanted to get out of the TD04 family badly. Mitsubishi-built "sport turbo" 13G's were dead reliable; the same turbos modified to 15G were good too but I think I rebuilt them once due to wear; then modded them to 17G size and I think they wore out twice pretty fast, just not so happy at high boost with NOS etc. kinda overdriving them.

13G's outstanding turbos, worth 50hp more than stock all else equal; 15G's great and more hp than 13G's; 17G mod was not happy due to longevity issues, and really didn't get much if ANY more hp/mph out of the 17G's...but confounding factor was odyssey of Web Cam regrinds with Kibblewhite Precision Machine upgraded valvespring setup they claimed was fine to .600" lift but I kept breaking outer valvesprings, wearing valve tips and rockers...finally measured the coilbind MYSELF and the freaking things were .030 from coilbind at the lift I was using, so finally fixed that but had been running on broken valvesprings, slightly tweaked/bent valves, wearing cams etc for like 2 years with the 17G's so maybe never realized their full potential.

For my HP estimates through the years (when not on dyno), I used the trusty Moroso Power Speed Calculator sliderule, Moroso part number 89650. You enter the vehicle's speed and weight, and it gives HP. You can enter in any 2 data, including hp, weight, ET, trap speed, weight/power ratio...and get out the other data. It assumes a fairly ideal launch for the ET.

For Matt's current 9.0 @ 157mph at 2920 lbs, gives ~860hp. All in all, pretty close to what 3SX and Matt are likely making. 3SX going 152mph gives around 790hp...so my calculator may be a conservative dyno estimate

Way back then I didn't have much weight out, so was around 3850 lbs race weight (stock car was 3780lbs, I had a little over 100lbs out of car, so right around 3850 lbs). 125.76 mph at 3850 lbs was about 580hp.

If my car weighed 2920 lbs back then, it would have been going about 138mph not too bad no NOS on 15G's.

When my 94 went 10.4 @ 138.76, it had dyno'd about 740hp with 50hp NOS jet. I used 75hp jet to do the 10.4, and Moroso sliderule with mph and weight (3680 with me in it, car is now around 3500 without me, has rollcage etc) says ~770hp. Pretty close! Certainly differences of +/- 10-20hp can be seen, and these are ESTIMATES.

If my 138.76mph 94 VR4 weighed 2920 lbs like Matt's, it would have gone about 151mph...so yes that 760 lb weight loss of Matt (and the 3SX drag car) make a critical difference, and explain why my street car/roadcourse car will never dragrace as quick/fast as them again.

But, you WILL see me driving my car to work again tomorrow, just like I did at Road America HP driver event Oct 14-15, and to buddy's house to watch the Packers beat Denver today radio on, power windows and all

Anyway, the "old turbos" were not bad, just had their performance evelopes. As for 19T's, if you have the compressor map you can SEE if/how much better they might be. The problem with the 14B wheels is their "B" design is less efficient at higher boost levels than G or T wheels. B are great low/midboost turbos, but may not be AS IDEAL at higher boost levels. The T comp wheels I have not used nor do I know their pressure ratio capabilities. More airflow can be great, but with only 3 liters you will need more BOOST to put those lbs/hr of air into the motor. I like the idea of bigger compressor AND HOUSING than the stock TD04 or 15G, but I have questions about the longevity of the TD04 center at higher boost levels; I'd prefer to get out of that series and into at least good but cheap EVO3 turbo setup if at all possible, for most people. I am sure Dynamic, 3SX, IPS et al can direct better than I, but I do NOT trust those tiny TD04 centersections at high boost.
Your Results May Vary!
Jack T.

[lawdogg]

So that means that a TD04HL compressor housing with a 15g-size compressor wheel is the best solution?

And if you bore your turbine housing, while maintaining the same A/R, you will see more boost?