Olds ticket to 9s... LS swap adventure.

[motorheadmike]

For street use stay with a safe, low rpm number and leave it there until 5K (above the peak TQ rpm). 8 might be conservative, but I wouldn't go over 12 deg below 5k on pump gas, just no reason for it. Uncle Rodney will appreciate that type of tune anyway lol. When you are at the strip it will live over 5k anyway at 3/4 of second past launching.

FWIW, my TBSS is set at ~11° under load (MBT) and she is a much heavier girl. I know I could throw a lot more timing at it (especially with the propane injection) - but, the juice isn't worth the squeeze relative to tossing rods vs kingsh*t HP claims.

You should consider methanol injection as a safety catch for a bad batch of pump gas. And you have to figure with the slow sales of fuel these days you could safely bet you're going to get some stale/shadey crap coming out at the pump.

 

[Northernregal]

For street use stay with a safe, low rpm number and leave it there until 5K (above the peak TQ rpm). 8 might be conservative, but I wouldn't go over 12 deg below 5k on pump gas, just no reason for it. Uncle Rodney will appreciate that type of tune anyway lol. When you are at the strip it will live over 5k anyway at 3/4 of second past launching.

I don't want to be Captain Obvious (in case you have experienced this already), but your description is the incredible part of a turbo car. I never expected what you describe above when we first started running turbos. Throttle position is almost irrelevant to HP production. Anything over 45-55% TPS and it's all the same as 100% - which is completely opposite of every NA car I've ever driven. The next anomaly is cruising at 70ish mph and hitting a mild grade. 2-5% additional throttle to maintain speed and the map reading will start approaching 90+kpa, almost zero vacuum, despite being at 12-18% throttle. Then you look down and your running 95 without any effort - it's ULTRA slick. If you datalog that you'll see the additional fuel getting thrown in to maintain 14.5-14.8 AFR reading.


p.s. - you beat me, I don't have plates/registration yet. Glad to see it!!

I've been turbo diesel forever, so I knew kinda what to expect. Lol
Still surprising, the open wastegate doesnt help though, it's an eye opener for sure.

I'll go get some data, post some of the datalogs and see what you more experienced guys think. Been difficult to get tuning opinions with the LS3 heads, not enough info out there for the faster burning chamber.

FWIW, my TBSS is set at ~11° under load (MBT) and she is a much heavier girl. I know I could throw a lot more timing at it (especially with the propane injection) - but, the juice isn't worth the squeeze relative to tossing rods vs kingsh*t HP claims.

You should consider methanol injection as a safety catch for a bad batch of pump gas. And you have to figure with the slow sales of fuel these days you could safely bet you're going to get some stale/shadey crap coming out at the pump.

Thanks Mike, I never thought of the fuel issue. Once I get the second pump on a hanger and a content sensor itll start getting E85, so that's keeping me from meth injection.

I have no plans to tighten it up to the edge on straight pump gas. The Holley system has safeties so if I get boost creep it wont grenade. I feel its about as safe as it's going to get for now, but I'll keep it under 5k, just to be saferer.

 

[motorheadmike]

I've been turbo diesel forever, so I knew kinda what to expect. Lol
Still surprising, the open wastegate doesnt help though, it's an eye opener for sure.

I'll go get some data, post some of the datalogs and see what you more experienced guys think. Been difficult to get tuning opinions with the LS3 heads, not enough info out there for the faster burning chamber.



Thanks Mike, I never thought of the fuel issue. Once I get the second pump on a hanger and a content sensor itll start getting E85, so that's keeping me from meth injection.

I have no plans to tighten it up to the edge on straight pump gas. The Holley system has safeties so if I get boost creep it wont grenade. I feel its about as safe as it's going to get for now, but I'll keep it under 5k, just to be saferer.

On the ethanol side of the house aim for E50-60 as a constant. There is sufficient evidence that shows diminishing returns past that point (BTUs), plus it gives longer legs to your fuel system in the event the pump(s) start failing or you have an overboost scenario.

 

[Northernregal]

Got 4 tuning runs in today. Turns out my fuel table was really lean, and I ended up down to 9 degrees at 8psi.

But the base is now way closer to where it needs to be. Awesome thing about the holley closed loop, really saves your skin when you are trying to get dialed in. Still having some boost creep, I can get to about 4500rpm and my 8psi ignition cut hits. Double checked the wastegate, it's a VS Racing 44mm, everything functions properly. I can function it with shop air and placement is in a good flowing position on the turbine housing. Verified it opens at 5-6psi on shop air.

Got a short clip of one hit. How fast it hits the boost ignition cut.

Enjoy.

I'm thinking once I sort out a few things on the wiring side (converter lockup and some other wiring cleanup) it's going to need some dyno time. It's too sketchy trying to do hits on backroads. Lol

 

[motorheadmike]

it's going to need some dyno time. It's too sketchy trying to do hits on backroads. Lol

The advantages of MAF over speed density is you can tune the whole WOT table in a run through 1st and 2nd gear. I hate that I'll be tuning the Monte on SD in OL.

 

[Northernregal]

The advantages of MAF over speed density is you can tune the whole WOT table in a run through 1st and 2nd gear. I hate that I'll be tuning the Monte on SD in OL.

I'm just thinking that it would be easier and take less time in a more controlled environment. Rather than risk a run in with the law for just dicking around with my fuel tables.

 

[motorheadmike]

I'm just thinking that it would be easier and take less time in a more controlled environment. Rather than risk a run in with the law for just dicking around with my fuel tables.

Agreed. Just highlighting how much nicer the Holley system is.

 

[Northernregal]

Agreed. Just highlighting how much nicer the Holley system is.

Oh man. I have to agree. It's a cool down wait between runs to pull the log, run it with your tune file loaded so you can see the exact cells in each area that effect whatever you want to change, then 10 seconds to reload and go.

Speaking of which. Here are my important fuel and ignition curves.

Still working the fuel VE map up so its a bit rough looking, but its getting closer, way closer than it was.

 

[Texas82GP]

We had a Griffin LS swap radiator in my brother's 78 Camaro. It didn't last long. Poor quality and worse warranty.

 

[64nailhead]

You never need to be 10.0 as a target AFR. 11.0 as a target is as rich as you need to get. 10.0 will wash the cylinders quick - ask me how I know. I’m still battling with the Holley, it’s not the same as a Megasquirt, requires you to be more intuitive, but it works well.