Hi All,

Dropping a Warhak LS7x in to Chev Lumina SS(South African version of the Pontiac G8)

I'm going to do away with the MAf but looking for advice on best location for IAT.
Just before throttle body or in air filter box.

There seems to be so many mixed thoughts online.

Thanks,
Jon

 

The temp should not vary enough to matter anywhere from the filter to the throttle body. The filter box would seem the most convenient place to do it and still be accurate.

 

Thanks G.

I'm new to the forum and tuning.
I have some injector related questions, who is the go to person on this forum?

 

If you had a forced induction setup, then there would probably be a mile of intercooler plumbing between the filter and the intake. So that is probably part of the reason you find so many people insist on putting it just before the throttle body. I personally will be putting it just before the TB for this exact reason. Although I may install a second one for reference, pre-intercooler, and switch back and forth between them to compare.

In your case, if the intake tube is short, and the swap is fairly 'linear' meaning it doesn't have any strange situations, like the air box isn't sitting on the exhaust or something, then the temp sensor location could be fine anywhere between the filter and engine. Just take a good look at it to make sure there won't be any strange heating of areas, and fabricate shields to prevent that.

 

Talon-
He never mentioned forced induction, so your entire first paragraph is irrelevant.
Your second paragraph repeats what I said, only with too many more words.

 

Its going to be an NA setup for now - maybe a supercharger down the line

This is the setup:
Block - Warhawk Ls7x - 9.240 deck
Heads -Trickflow 225cc Cathedral port heads with 1.7 rocker ratio
Cam - Trickflow - 286/282, Lift .575/.575, Lobe Sep. 112, 220 int./224 exh. ?LS1
Pistons - Manley -11cc
Crank - Callies, 4.000 , 58x reluctor
Connecting rods- Callies
Head Gasket - Cometic .045Mls
Damper - ATI
Cluth - Mcleod Twin RST
Heavy duty slave and custom 1" adapter plate
Intake manifold -Holley Sniper
TB - 90mm gm electronic
Headers - Long tube ( TNT - South African made)
Cole Hersee remote solenoid - ( MSD and stock starter were getting heat soak as headers sit 5mm away from the solenoid)
Starter - MSD
Oil pump - Melling Hi vol
Oil cooler
Morso 7qt pan
Double roller chain and timing set
All new sensors - including removal of MAF with stand alone IAT
2.5inch exhaust system - cats removed
Plug leads - 10.4mm
Coils - Stock L98
Accessories - Stock, ac, water etc.
LC1 Wideband
HP Tuners Pro logger
E38 Gen 3 PCM
T56 6 speed manual transmission
Short Shifter - 25% throw reduction
CTS-v Brembo - 4 pot front calipers and vented rotors
Rims/Tyres - 245/35/20 Front , 275/30/20 Rear

Still have no Idea what kinda HP I could expect

 

I tend to go the other way on this. I prefer IAT getting closer to fresh air to get ambient temps. You get heat soak on the intake piping that causes falsely high temp readings, resulting in leaner than expected conditions.

 

As a manufacturer, they are removing fuel for increasing IAT in the stock tune file, naturally to help preserve the exact chemical ratio of fuel to air (the reason they often use both MAF and MAP).

As a sole tuner, or owner of a high performance engine, this will never happen. (this should never happen IMO). I will never pull fuel from some 100% baseline IAT value to 98% or 96% as the IAT moves from say 80*F to 120*F. If it hasn't kicked in yet why, let us talk briefly of combustion reaction chemistry, where it starts at some T and ends at some T, usually the second T is higher when burning fuel in a piston engine when modelling combustion reactions but it doesn't have to be all the time for every reaction.

As a sole tuner, instead, I will be monitoring IAT "below 100%" (when the air is hotter than it should be) and I will do everything I can to ensure that when the IAT is going up that perhaps MORE fuel is available to the engine (my IAT might even rise 102% 104% going up to 130*F for example) These efforts I make, against factory implementation you described above, to help cool the engine. Assuming the additional fuel is able to actually cool the engine enough- remember that the octane of the fuel is reflected in the T Temperature and changes the safety of where we begin (or possibly end) in reactions, i.e. Higher Temperatures usually mean faster reactions, and faster reactions in lower octane fuels means engine knock conditions are more prevalent. That means that there is some Temperature at which that my engine is in danger of engine knock even with what should be a reasonable timing number at lower temperatures. There also exists a 0-octane (n-heptane or n-octane one of those) fuel which would never run in any of our gasoline engines, but probably looks and smells alot like gasoline, except because it packs better in straight chains it should exist as a solid sooner (at lower temperatures). Why do you think this fuel has zero octane? And is there a low enough Temperature where we can use 0 octane fuel?

I don't have all the answers. But here is the final countdown: You need to know the starting T of the combustion reaction for all tuning and safety programming of the engine.[/COLOR] That means I need to know the temperature of all the air just before it enters the cylinder, I need 8 individual temperature recorders that won't heat soak installed to each intake runner ideally. If I can't have that I put one in the next available, affordable, reliable, simple location, that is as close as possible to the cylinder. This is generally just prior to entering the intake manifold.

If you can you also want an IAT before the intercooler so you can see if your intercooler is doing anything. Sometimes the T before the intercooler is 98*F but the T before the throttle body is 114*F, after the intercooler. Some compressor covers are 350*F all the time, so it depends how big everything is and how much time air spends in that area, how hot it will be in compressor cover applications (your favorite)

 

Your small heads & cam is an unusual combo with the
Sniper Intake Manifold on a 427".
And holding it back BIG Time.
You would Pick Up 80-100+RWHP & 50-60 lb ft
for a HUGE part of your Driving range 2500-6500+ RPM

By upgrading to Mamo MOTORSPORTS LS7 Heads &
Ported MSD or FAST with a relatively small cam
~234*/244* .630"/.610" LSA 114*+3*

 

Thanks Navy,

The heads, block and cam were not my choice. I inherited the project from my late father, he had purchased those items about 7 years ago but just never got around to building the engine. I'm not sure what heads and options were around then, but I think his plan was to either supercharge or t/turbo.

The sniper unit was a compromise, mainly due to cost and all the money I had to spend buying the parts I required to get her going (close on $12000 so far) - our exchange rate is ZAR14 to 1$ - I did look at the Fast/MSD intakes but after duties and shipping would have been the equivalent of you spending $15000-$20000 on an intake.

My plan is hopefully to fit a supercharger so the sniper will eventually get done away with.

In your experience what kind of HP do you think I could expect with this current setup? I'm trying to figure out where I land with injector sizing as my stock are 42lb @ 43.5psi - static 58psi returnless fuel system. I bought some 60ls@43.5psi remanned units of eBay from TLF Performance but was basically told they are **** and I shouldn't waste my time trying to tune them.

Thanks for the tech info Talon.