Cai..

Chuck Leeper

Toxic old bastard
Staff member
Joined
May 28, 2001
In the "FWIW" dept....:cool:
Just completed some data logging on the LS in my 55.
Disappointing inlet air temps as high as 129*,were recorded, w/ the K&N under the hood. The tune is pulling almost all the timing when in power enrichment. AKA: WFO! 5* left out of 25*...[Truck tunes tend to be a lot more conservative than Vettes, F-bodies, in this area]
So, I decided to instrument the car for some real time logging of air temps.
Here's what I have w/ the thermocouples installed: 1,[labeled T1], at the cleaner element, 1, [labeled T2], in ft of the air inlet screen I've put in the core support panel.
Engine cold/off/hood closed/in shop. Ambient 84*F. Both sensors reading the same @84*.

Engine started and at 125* T1= 98*, T2 = 92*
Engine @ 165* T1 = 110* T2 = 103*

Moved car outside, ambient 91*, engine idling, 180*.
T1 = 116* T2 = 102*

Driving, engine temp @192*, ambient 94*. Humidity 43%.

T1 MPH T2
122* 30 95*
131* 40 95*
138* 50 94*
138* 60 94*

Since I was considering making a cowl inlet system, I logged some temps comparing the core support inlet temps with the fresh air inlet temps at the dr side duct.

Engine 191*, ambient 96*.

T1 is now the core support inlet temp, and T2 is the inside air duct temp.

T1 MPH T2
121 0 100
104 40 102
97 50 100
96 60 99
96 90 99

It appears that the cowl sheet metal has encountered enough heat soak, that the effort to use the cowl, will not provide an advantage over the core support inlet. [And, in most scenarios, be not as efficient]

Comments? Suggestions?

Next testing will be w/ a different shaped K&N, operating in a sealed plenum hooked to the core support opening. We'll see....

This info would apply to any air intake system. I just happened to have the LS in my 55...:D
 
Hard to tell for sure but I would be willing to bet that the engine heat rising out from under the hood into the cowl area is the culprit. Reflective heat from the glass windshield may come into play as well.

I don't know how your engine bay is laid out but have you tried putting the filter in front of the radiator or behind the bumper in a "dead" area that is less affected by transient engine heat?
 
Also pulling from too low on the car up front picks up asphalt heat at lower speeds.

Also consider fan wash heat at low speeds.

I would think that a boxed off area pulling from the front of the car would be best.

Thanx for posting this up very interesting tech.
 
Yep..

"I don't know how your engine bay is laid out but have you tried putting the filter in front of the radiator or behind the bumper in a "dead" area that is less affected by transient engine heat?"

The core support temp readings, [T2], are from in ft of the opening, [5x7"], I have made in the support filler panel.

The cowl area is a likely place, once the car is out on a long run, where the cowl air temps can be lower..[I ran out of country road, during the testing!]:eek:

"I would think that a boxed off area pulling from the front of the car would be best."

That's where I'm headed. A lot less work to get virtually get the same benefits..

I also knocked about 10* of timing retard out of the PE vs IAT table..Pulls ALOT better at the hit, too!:D
Once the plenum box is in, I'll try to take most of the remaining 10* out, and see what shows on the logs...

Here's a couple overall shots of the engine compartment.[You can see the inlet screened port at the core support.]
The new arrangement will use a oval K&N, and a 90* pipe arrangement to get the filter and MAF inside the box, and directly in line w/ the core support inlet.
With the current truck intake on the engine, it's a "dead player" after about 5500. So, outrageous cfm is not a requirement.
A 150 shot might change that, tho...:eek:
 

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hello; I just saw a 427 concept truck on the net and it has a boxed in intake filter. It looks good as long as you can get fresh air to it. It might be the way to go.
IBBYi
 
A couple mor...

Here tis..:D
All the creature comforts for cruizin..P/s, p/b, a/c/, p/w, hidden stereo.
LQ9/4L65E/9" w/ 3.50 Dl, 17" Billet Streetlites.
May even get a 150 "shot"!!!:D:D
 

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Trailblazer SS intake or 2007 and newer reg truck intake and 90mm throttle body show 20 rwhp gain I think you need one with a 150 shot plate system
 
Leave it alone and drive it Chuck!!! I'll try to get some pics of my swap up in the next day or so..
 
Impressive !

Hi Chuck,

Would you mind sharing a few details on your build ? I am looking to upgrade my 55 210 with a 6.0 LS motor and have a few questions.

Whose motor mounts, headers, LS wiring harness/computer did you use?

I noticed you moved the AC compressor to the higher position rather than notching the frame, whose mount did you utlize?

Where did you mount/hide the computer at. My car has the vintage air setup so under the dash really isn't an option.

What fuel tank/system are you using (spectra/intank pump, external pump/sump stock tank, Ricks hot rod stainless) ?

Any info would be helpful...what worked and what to stay away from.

thanks for your time.
Jason Hall
 
Details..

Hi Chuck,

Would you mind sharing a few details on your build ? I am looking to upgrade my 55 210 with a 6.0 LS motor and have a few questions.

Whose motor mounts, headers, LS wiring harness/computer did you use?

I noticed you moved the AC compressor to the higher position rather than notching the frame, whose mount did you utilize?

Where did you mount/hide the computer at. My car has the vintage air setup so under the dash really isn't an option.

What fuel tank/system are you using (spectra/intank pump, external pump/sump stock tank, Ricks hot rod stainless) ?

Any info would be helpful...what worked and what to stay away from.

thanks for your time.
Jason Hall

Jason,
I made my own engine and trans mounts. The engine mounts are on the ft x member, instead of off the side of the frame rails.

The A/C mount is made by KWIK Performance.

The PCM and TAC modules are under the pass side of the seat.[I have the V/A ac unit, too.]

The fuel tank was a bargain that I got used. It's a Rock Valley stainless, with the pump internal. The pump is the turbo Supra unit. I plumbed the tank for a return system, as I use an Aeromotive adj reg.
[You can use the Vette reg/filter, and do away w/ the return from the rails, if you want. Less $, and easier to do.]
I used the stock truck exh manifolds. Had to angle mill the dr side to clear the 500 p/s box.
Send me your email and I'll send you a bunch of pics...[Any TR swappers: If you want some pics, PM or email me.]

For the TR guys... This is a list of items that may be used on the Buicks, so don't get your panties in a wad!!:D:D
 
CAI update...

Made a "box" with cardboard, to attempt sealing the cleaner element to the core support opening. Semi successful:
Ambient today is 93*.
The T1/T2 probes were used again.
T1 was inserted into the box, next to the element. T2 was in the engine compartment.
Driving @ 40-55mph cruise rpm, the box temps stayed right at 93*, while the engine compt. went to 127*
2 WFO blasts to 100: 104@ the dig, to 111@ the "stripe".

Drive/cruise temps [read in the sensor in the MAF], =99*. I think I had enuf leaks in the box, [plus, cardboard is a poor shield], that w/ a good metal box, well insulated, I can get really close to ambient IATS.
Using EFILIVE allows for tuning on so many correction/multiplier tables, it makes the head hurt:D
You LSX/TR converts should look into EFILIVE... It's the "bomb"..:biggrin:
More latr!:cool:
 
Mr. Chuck, Ever thought about an Alky kit to cool the charge? I know its not lowering the underhood temperature, but could cool the air charge in the pipe. Just a thought sir.
 
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