Homeslice (tm)

Some of you may remember myself and White2001S10 having some spirited threads in here about our setup..... well the guy who bought it from me, Kolk1 who gratiously allowed further rigging and jimmying for science, has posted up some numbers gleaned from his recent maiden dyno runs.

This is a stock bottom end LS1 with stock casting home ported 98' LS1 Heads, sporting a GT2-3 cam (207/220 .573/.580 117.5 LSA), 1.85:1 adjustable rockers, ls6 valves, 918's. Single nozzle dry setup in the air bridge. Car is speed density and uses the CTS tricker box to do enrichment for the bottle.


371whp and 384 wtorque on 87 octane

527whp and 544 wtorque again 87 octane.

Very conservative on 87 octane... no additional fuel. Ready for more bottle.

Kolk1

And that was only on 1/2 of the shot we have planned

CAT3

iTrader: (9)

Looks about 150 Dry there. Nice info. Why use 87? Is nothing else available, or you like to tune on lower octance for more hp rahter than higher octane? Interesting. I guess if you can do it, reat. If you dont mine, what is timing from 4,000-6,500rpms above the .76 g/sec-1.20g?

Kolk1

That was only a 125shot, and it hits harder than my 150 shot in my Camaro. Ill let Bo or Mike answer the rest.

CAT3

iTrader: (9)

kolk1, ok you say 125 shot, but I say 150 since thats what it put out. Funny thing about the dry it is more dependent on bottle pressure/nozzle placement for jet selection than wet kits are, but anyway. Thanks and will look back.

Kolk1

You can say 150 shot all you want, I was at 950 psi, and about 6inchs from my TB, same as my Camaro. According to NOS, its jetted at a 125shot, and according to NOS my camaro is a 150shot.

Yes I know it added 150hp, but its only jetted for a 125, at 950psi.

CAT3

iTrader: (9)

Ok fair enough. Glad we understand eachother.

Homeslice (tm)

Yup yup... doesn't matter the pill size it gained 150. The important thing is that the heads are working and well for the bottle. Anytime you make or exceed the rated power to the wheels on a given pill / pressure your combo is working well. I'm thrilled with the way the engine performed.... can't wait to see what it is really capable of.

I'm sorry I don't have a working copy of the flash that was in the car for the dyno pull to give you real timing numbers... maybe White2001S10 will chime in here with the specifics.

CAT3

iTrader: (9)

I would say the cam is working pretty good also. I was interested in swapping to a smaller cam like that, but hadnt really looked into whether it would be compatible for large nitrous. I know the FI guys seem to do good, but again, none I heard running over 600rwhp with it. Not to say the cam wont flow, but not sure anyone is really pushing them. I have no clue what the jet and pressure relationship is..other than looking at a chart and saying xx pill should be xxx hp, but I havent been messing with jets for a while. I just know dry seems to be little more picky on where the nozzles are, pressure etc.. I'd like to hear more about this car, sounds like a very sweet little "mild" appearing setup.
Charlie

aram

iTrader: (7)

Why would you run that car ever on 87 ?

Seems like it's the equivalent of pulling one spark plug wire and getting excited at all the power you made on 7 cyls?

CAT3

iTrader: (9)

aram, lower octane burns quicker, and has the potential to create more power if tuned for it. We use race gas to deter pre-ignition, basically we control the flame propagation by higher octane thus preventing more power from being unlocked. Basically most ppl compromise, use more octane to make more power, instead of tuning for lower quicker burning low octane....at least thats how I understand it. But I am curious why the use of the 87, maybe it was to prove a point, like they could?

white2001s10

iTrader: (4)

It runs an OLSD tune.
One of the big advantages of not running O2 sensors is that you can mix race gas in the tank to bring the octane up when needed.

Most cars actually run better on 87 octane about 99% of the time.
This car was tuned to run on 87 and has slightly reduced compression along with polished chambers & valves. It also runs very cool when going down the road, though maybe not so much set up for running on the dyno.

The timing is 27* at torque peak, 29* HP peak when NA.
It drops to 22* torque peak and 27* HP peak when set for the smaller shot.

The curve is actually not set for taching out 3rd gear under load and on the bottle, which would theoretically be holding WOT until exceeding 160 MPH due to the highway gears.

A more dyno-specific tune with manually locking the converter would've produced better numbers for sure.

98redorangeta

iTrader: (10)

Damn olsd on a dry shot and 87 octane you really wanted to slap convetion in the face didnt you

CAT3

iTrader: (9)

Figured it White is in the mix it would be OLSD, didnt want to specifically ask about that though, since we already talked before. Sounds like the work on the heads, polishing etc really has paid off, as well as the rest. Your always one to watch.

Homeslice (tm)

Actually it works out to be a much much more predictable setup. Using the tricker to do enrichment and eliminating the variability of CL operation allows many specific tunes to be stored and used at will by varying the CTS input.

As white mentioned the 87 usage is a no brainer.. octane is for one reason only, detonation prevention... why use more than you need? The car actually slows considerably on 93.

CAT3

iTrader: (9)

What is CTS? Is that the Vette = of IAT for F Bodies? Damn nice setup no matter what you look at it.

Robert56

iTrader: (2)

Homeslice, good to hear from ya, and also white2000. We had some good threads in the past. A couple guys that really understand what's going on in the n2o world, and especially the dry. This goes back a few years when dry was really getting a bad rap, but people are realizing that dry hit can work pretty well. Open loop SD tuning I have considered, however, I am not done playing with CL yet, so many tuning options and ways to do the dry. Congrats on another fine working set-up.
Robert

Kolk1

CTS is the coolant Temp sensor, If I want 15% more fuel, I just dial the Coolant temp to 230* using a potentiometer and I have 15% more fuel, and its an upward ramp. It also changes my spark, heres the table.

Spark:
From 131F to 185F your spark stays the same with 0 retard.

194F -0.5*
203F -1.0*
212F -1.5*
221F -2.0*
230F -4.0*
239F -5.0*
248F -5.0*
257F -5.0*
266F -8.0*
275F -8.0*
284F -9.0*
_____________________________________

Fuel:
From 140F to 212F your fueling stays the same with 0% added fuel.

221F +10.0%
230F +15.2%
239F +17.7%
248F +20.0%
257F +25.0%
266F +30.2%
275F +40.0%
284F +50.0%

CAT3

iTrader: (9)

Since I havent messed with the OLSD any, cant the same thing be done with just PCM tuning in CL, or OLSD rather than using a pot? I see the advantage of using the pot, which I had got some info prior to this from White about. However, unless you want to selectively run different sizes of nitrous, then it seems just as feasible to tune the PCM using the parameters already in the PCM, like Advance vs ECT, FA Mulitplier vs IAT etc?

Kolk1

If you didnt use a Pot to change coolant temp, to add fuel, and change timing, How would the PCM know to add fuel, if you were tuned OLSD??

Im not good with tuning, so thats a real question.

I can see how if the MAF was still on the car it would know to add fuel, thats how we did the camaro.

Im speaking in strickly dry shots here.