vette.se

I need to change the ETC Area Scalar but I'm not sure I'm doing it correctly.

It's my understanding that I only need to change the ETC Area Scalar on a Corvette C5 to use a larger throttelbody, correct ?

The Harrop intake got eight 55mm throttels, each one has a area of 2374.63 mm2 making it a total of 18997 mm2 - the stock 78mm throttelbody has a area of 4776 mm2. So.......

4776/18997=0.2514, the stock ETC Area Scalar is 0.0255 so 0.0255*0.2514=0.00641 which is the new ETC Area Scalar value, correct ?

miami993c297

iTrader: (6)

Following your calculation for a ZO6 with a LS2 90 TB we do:

LS2 90mm area= 6361.74 mm2

4776/6362=0.7507

0.0255*0.7507= 0.01914285

The new ETC Scallar for the LS2 TB 90 mod is = 0.019143

Is that correct?
Christian

TUF383

Email me via ken@harrop.com.au & I will send you a HPT file that is good for the Hurricane so you can view what we do.

miami993c297

iTrader: (6)

Hi TUF383,

Would you mind to let me know if the formula for the calculation of the ETC Area Scalar is the good one and if my results for the 90 mm TB on a 2002 vette are correct?

Thanks
Christian

miami993c297

iTrader: (6)

I am not getting any answer to my questions because:

- No change needed...

- None of the tuners here around have a clue.

- No one is running this mod !!!!!

- I am asking in the wrong forum ???

- It is a big secret in the fraternity and the one that knows will keep it to the end

Christian

SSpdDmon

iTrader: (10)

You have 8 throttle bodies???? Isn't that a little excessive?

miami993c297

iTrader: (6)

For those interested in the answer to my question I found it on:

http://forum.efilive.com/

Christian

vette.se

Thanks for all replies !


60hp more than a FAST 90/90 (427C5R engine)

miami993c297

iTrader: (6)

Hi vette.se,

Do you have already some dyno data ?

Do you have pics of your install in the Corvette?

How is the drivability and how is the tuning going on?

Christian

vette.se

I have a dyno sheet from one of Harrops customers, the gain is around 60hp.

I will post pictures of the install this weekend. If you dont like cutting in your car this is nothing for you .... you have do cut away a lot of the glassfiber closest to the rear of intake to make it fit.

This is the dyno sheet - I'm not sure if this is a 350' LS1 or a 427'

miami993c297

iTrader: (6)

Can't wait to see the pictures of your install....

If you have a chance add a video clip, with the sound of course!!!

This mod will certainly fit some huge camshaft overlap very nicely.

Christian

vette.se

Installed my G5XX a week ago

miami993c297

iTrader: (6)

That seems to be a "good starting point" in term of overlap...

The idle is going to be the surprise, on the side of the power.

May I obtain a little more info on your set-up???

Christian

vette.se

The G5XX is suprisingly smooth in a large cubic engine and idles at 1000rpm. Anthony at LG told me that there is quite a difference between a 350' and 427' with this cam.



You can see the stock stepper motor and TPS sensor in the lower picture. Harrop has this setup for cable driven setups as well. I have removed the airboxes because they do not clear my raised valvetrain covers and MSD coils.


A little about the current config ....

Corvette C5 FRC -00 (DRM C500RSR built by Doug Rippie Motorsports), used as street and roadrace car - no dragracing.

427C5R
DRM ported LS6 heads
CompCam 921 spring kit
CompCam ChromeMoly pushrods
Jesel Mohawk rockers
Morel lifters
LG G5XX cam

Fuel system built by vette.se 8AN feed line, using stock line as return, Magnafuel MP9950 regulator, Racetronix pump system - we should be able to feed 750hp with this setup (fuel pump being the week link)

I've sold my FAST 90/90 setup to finance the Harrop Currently using a stock LS1 intake with stock 78mm throttel - this setup runs out of breath at around 3000rpm (Intake kpa drops from 101kpa to 96kpa at 2800rpm)

This is my last post in this thread - this is not related to PCM programming any longer ..... will start a new thread in the LS1-LS6 External Engine with pics of the install - sorry, no install this weekend, I did not get the fuel line hardware in time for the new fuelrails.

pkincy

iTrader: (1)

Puhlease keep us posted with lots of pictures and posts.

thanks,

RedHardSupra

iTrader: (1)

well, if you were so kind to post some logs of how this baby flows air, it would make it an excellent PCM thread

my question is how do you approach tuning 8 throttlebodies with a computer that's designed for one? with one TB, you get constant airflow through it, but with a 8 TBs, most of then can be closed, as they're not providing airflow to their cylinders. so would we calculate the effective area would for 1 TB, not 8 in this case? or do we calculate it for 8 becuase that's what the computer expects to get, and it divides it by number of cylinders to get cylinder airmass anyway?

Christian: is this the thread you're talking about, or did you find something better? http://forum.efilive.com/showthread.php?t=4816

vette.se

We will calculate for one VERY big throttelbody

If you look at this picture you will see that all throttels are controlled by the stock stepper motor - acting as one throttel.



The quality an precision in this Harrop setup is incredible making it possible to set each throttel to have the same fully closed/fully open position to at least in theory have the same airflow through each throttel.

miami993c297

iTrader: (6)

Hi Marcin,
That's the one...

I am trying 0.0157 for the Area Scalar in my Bin File presently...
Any advice?

Christian

vette.se

My Harrop is finaly installed and running The ETC Area Scalar of 0.00641 seems to work very well.

See https://ls1tech.com/forums/generation-iii-external-engine/703859-harrop-8-throttel-intake-finaly-installed.html for some pictures.