Pauls325

iTrader: (1)

welcome friend hopefully you picked the guys brain a bit..... if you dont mind im curious as to what your background might be.... and if you found out his.

dbtk2

Way more than I'm comfortable with although i saw no kr in my scans. Timing was peaking around 17 degrees with map ~175kpa. Looks like its set to pull a good amount with IATs above 70* but its like 15* out so they're not up there yet.

I didn't really pick his brain at all on the setup. Other than the custom work to make it fit its not anything weird/crazy so nothing i felt i needed to know. Its an ls motor with a tvs1900 on it...pretty common.

As far as experince I've been building/racing 3800 stuff since '03. Set quite a few different dyno records and a few 1/4 mile records over the years. I worked at ZZP for a couple years building turbo and sc 3800 stuff along with a few ls4 builds, and also ecotec stuff as well as dyno tuning for all of the above. Got pretty familiar with 600+whp fwd stuff.

I daily drove a "fully built" M90 3800 setup for about 5 years that i also sprayed a 125 shot with (made 403whp and went 11.2 @ 124 off spray) Got plenty of experience fixing those garbage transmissions over the years between my car and all the others I've built/fixed.

I've also done a couple LS swaps into older cars along with quite a bit of tuning on LS stuff. I also own a 06 GTO with a M112 on it.

I've browsed here for probably a decade but never had any need to post before now.

I'll keep you guys updated on progress of the car.

spawne32

iTrader: (2)

17* is not surprising with 15* temps outside, the factory IAT retard tables should more then make up for whatever knock you stand to have at 17* in normal weather.

91parkave

iTrader: (4)

That's pending a iat relocation though. Monitoring pre blower only does so much. Curious if the current setup had it relocated. To the manifold

dbtk2

IAT is not relocated, it was reading in the 40s since its just an open filter. But yea timing will drop fast when it warms up a little. 17 degrees doesn't really bother me other than knowing the stock downpipe is smaller than 2" in some spots. Haven't thrown the wideband on it yet so who knows what the fuel looks like.

91parkave

iTrader: (4)

Iirc maybe the 05 06 has 2 iat tables to utilize i know 07 08 does and could be Wired in and enabled

I'm also curious why the need for reverse rotation blower and al

spawne32

iTrader: (2)

Relocating to the manifold is only going to cause fueling issues between winter and summer months. I've been through this before with plenty of blower setups. The IAT and tune are not designed for monitoring blower temps, they are designed to adjust fueling from IAT based on whats coming into the intake. You can easily tune out any ignition related issues based on this as post blower temps are more consistent vs seasonal air temps. An intercooled blower can range from 125-150* IAT post blower, which is a marginal change in timing. Where as the swing from using the IAT in a place it doesnt belong can swing AFR's from 12:1 in the winter to 10:1 in the summer.

91parkave

iTrader: (4)

It's not relocating, you realize there's provisions for 2 iats in the blower housing already right?

spawne32

iTrader: (2)

THat is not what I am referring to, as far as our engines our concerned, our tunes are designed specifically to read IAT's in the intake track itself. Not post supercharger. Not to mention the fact that measuring post supercharger is the incorrect way to measure IAT's. Take note of the fact that ALL 3800 SC cars use the IAT in the intake just in the same manner that NA cars do. It is vital for a modern car to know what the temperature of the air is coming into the engine BEFORE it is heated by the supercharger, as calculations of air density based on this are vital to fueling. If you have the IAT after the blower, the IAT reads consistently hot, which gives it less of a range of auto adjustment for fuel when the temperature changes from 20* to 90* outside. The car might run smoothly in one temperature, but as the season changes, you will have to retune.

91parkave

iTrader: (4)

Even throwing out a 3800sc calibration point is irrelevant. Archaic at best. WE are talking about ls9 specific stuff which in this case the op is using. The ls9 does in fact use 2 iats pre and post and a bbv.

spawne32

iTrader: (2)

Ill repeat it again, for OUR tunes, meaning our E67 ecu that comes with our cars, NOT an LS9 ecu. They are designed to read the IAT from the intake track. Unless you change to a stand alone system or an ECU/tune setup that is programmed to account for post blower IAT's, it is incorrect to put the IAT sensor after the supercharger. This has nothing to do with ports on the intake manifold, this has to do strictly with the engine tuning.

lVloses

iTrader: (1)

07+ LS4s come with the e67 ECU as well as the LS9. So it should be as simple as wiring in a new IAT and turning it on in the tune.

spawne32

iTrader: (2)

You could use it for the torque management and secondary IAT controls, but you cannot use it as a replacement for the IAT in the intake, as once again the issue comes into play where you confuse the fuel tables on the car. Wiring the secondary IAT for safety reasons, assuming the ECU will take the pinouts properly, then it becomes as simple as enabling it on the torque management tab for SC. BUT you cannot write an LS9 tune on the car and expect it to work either. GM came up with some unique stuff in the E67 for supercharger controls but it still comes down to the fact that the IAT sensor used for fuel control has to remain in the intake preblower. GM has recognized this from the earliest of 3800 SC cars which you could use as the basis for tuning here, as we share parts like the MAF with the 3800 of our model generation.

91parkave

iTrader: (4)

You realize how many 3800 sc motors blew up with chipped pistons? Accounting for air temp on both sides is key to longevity point blank. Hp tuners/efi live already has the option to turn on alot of supercharged related stuff.you don't need the os, but you can't use the tables and modify accordingly

spawne32

iTrader: (2)

Chipped pistons has absolutely nothing to do with the IAT sensor location, ive been working with 3800's for 10 years now and chipped pistons is a common problem due to too much hp for the cast pistons in the 3800, nothing to do with IAT's. My buddies 3800 had a chipped piston in it for 5 years too, never ran lean, never pinged, it just made over 350hp and 400ft lbs of torque to the wheels which was too much for those cast pistons. Not to mention there are plenty of other supercharged cars that dont utilize post blower sensors, same goes for turbo cars as well, equipped without post turbo IAT's. The secondary IAT you are trying to rewire here again has nothing to do with fueling, it has to do with torque management and engine safety. When the IAT2 exceeds a value, it cuts boost, assuming you have the electronic boost bypass. As you can see by your diagrams in pimpalas post, the IAT in the MAF is still utilized.

Bigredraceing

how is the tuning going?