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Old 02-07-2016, 03:27 AM   #1
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Default Fuel Ve Values Really High

Hey kids im new to this whole turbo/tuning/hope my car doesnt blow up thing, and ive got my little slow mobile running fairly well with VEAL but all my values seem very high, im sure ive over looked something minor and help would be appreciated. Car is a '89 1.6 with a diypnp running an intercooled Greddy turbo kit with a td04h.


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Old 02-07-2016, 03:45 AM   #2
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fix your req fuel
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Old 02-07-2016, 03:49 AM   #3
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req fuel is 11.7
running stock bluetop injectors
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Old 02-07-2016, 04:50 AM   #4
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Quote:
Originally Posted by mewse View Post
req fuel is 11.7
running stock bluetop injectors
Your injectors are far too small. You're adding fuel and they are maxxed so you're adding more.

Hence high ve.
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Old 02-07-2016, 10:45 AM   #5
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Quote:
Originally Posted by mewse View Post
req fuel is 11.7
running stock bluetop injectors
As Dann mentioned, at that req fuel the max rpm you can support is ~5200 rpm. Injectors should be sized such that the req fuel is ~8.3msec for a max rpm of 7200.

Edit: and this would be 100% DC ... Bad

You are def in go boom territory

Edit (again): math is wrong up there, but yes bigger injectors

Last edited by Ted75zcar; 02-08-2016 at 12:24 AM. Reason: Bad math
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Old 02-07-2016, 06:22 PM   #6
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Future of your engine:

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Old 02-07-2016, 06:39 PM   #7
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New injectors it is then! Thanks guys <3
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Old 02-10-2016, 12:30 AM   #8
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Alright so ive obviously done a dumb somewhere, ive upgraded injectors to the 305cc from a 7mge and adjusted the req fuel (which is now 8.8) but the values are still more or less the same idling at 14.7 =/
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Old 02-10-2016, 02:33 AM   #9
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If the output pulsewidths are reasonable and your maximum duty cycle is within reason it doesn't really matter.

If you want you can double req fuel and halve all ve values. The only thing that doesn't automatically scale on MS2 is cranking pulsewidth.
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Old 02-10-2016, 09:49 AM   #10
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Quote:
Originally Posted by Ted75zcar View Post
As Dann mentioned, at that req fuel the max rpm you can support is ~5200 rpm. Injectors should be sized such that the req fuel is ~8.3msec for a max rpm of 7200.

?
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Old 02-10-2016, 10:15 AM   #11
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Quote:
Originally Posted by Braineack View Post
~sigh~

You will notice I edited admitting a math error (shortly after the original post). But thanks for checking!
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Old 02-11-2016, 03:39 AM   #12
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Problem solved! soooo...bad wideband sensor ground anyone? but all seems good now, although ive got a hesitation on light acceleration that sometimes causes the engine to stall.

Last edited by mewse; 02-11-2016 at 04:03 AM.
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Old 02-11-2016, 03:59 AM   #13
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3.something is probably an OK pulsewidth for idle, though it seems a bit high to me off a wild guess.

The other number you gave me, 21ms at 3100 rpm, That's kinda useless without a map value. 80% duty cycle is 25ms at 3100rpm though, so it's not locked open yet.
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