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return line question

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Old 12-16-2014, 11:53 AM
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Default return line question

I have a dumb question? (When won't I) I have a 98 ls1 from a camaro,that's going on my nova, now this engine has a return line from the rails. My question is can is plug the return? I will be using corvette fuel filter that has the return on it. Would there be any problems? Issues or concerns I should have?
Old 12-16-2014, 07:54 PM
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I have the same question. I have a 5.3 and wanna run the vette filter and keep my stock rails can I cap the return and remove the vacuum from the regulator.
Old 12-16-2014, 07:59 PM
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Certainly.
Old 12-17-2014, 01:43 AM
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Originally Posted by RockinWs6
Certainly.
Will there be any issues if I do?
Old 12-17-2014, 12:08 PM
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Originally Posted by on a bugdet
Will there be any issues if I do?
No why would you? all the newer corvettes and fbodies don't use a return. The only issue I know of is the tune for a non return system is different because the power enrichment is done with the injector pulse.

With the vacuum operated pressure regulator the fuel pressure rises on low vacuum.
So you would use 99 up corvette tune Or a 99 up fbody tune.
Old 12-17-2014, 08:12 PM
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Originally Posted by RockinWs6
No why would you? all the newer corvettes and fbodies don't use a return. The only issue I know of is the tune for a non return system is different because the power enrichment is done with the injector pulse.

With the vacuum operated pressure regulator the fuel pressure rises on low vacuum.
So you would use 99 up corvette tune Or a 99 up fbody tune.
Thank you.
Old 12-18-2014, 11:26 AM
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one more question??? if im running the fast ez efi ls2.0 and it askes do I have a return style system, do I say yes cause the vette filter has the return in it or no. also will the fast system still be able to do the self tune since it doesn't use vacuum for fuel inrichment.

thanks for your help
Old 12-19-2014, 01:13 PM
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Originally Posted by RockinWs6
No why would you? all the newer corvettes and f-bodies don't use a return. The only issue I know of is the tune for a non return system is different because the power enrichment is done with the injector pulse.

With the vacuum operated pressure regulator the fuel pressure rises on low vacuum.
So you would use 99 up corvette tune Or a 99 up f-body tune.
The tune is different, but it's actually just the injector calibration data...with a return and vacuum referenced regulator the pressure across the injectors is always the same...always 58 PSI across the injectors. With a return-less system, there's 58 PSI in the line, but the pressure below the injector changes...so the injectors become larger with more vacuum.

The only actual change necessary in the tune is in the injector flow rate table, as well as the offset table that references manifold pressure.
Old 12-19-2014, 01:15 PM
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Originally Posted by x275radial
one more question??? if im running the fast ez efi ls2.0 and it askes do I have a return style system, do I say yes cause the vette filter has the return in it or no. also will the fast system still be able to do the self tune since it doesn't use vacuum for fuel inrichment.

thanks for your help
If you're running the Corvette system, say no, that's technically return-less because it always puts 58 PSI at the rails, regardless of the engine vacuum.
Old 12-22-2014, 06:08 PM
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Thanks for all your help and clearing that up for me. I'm a carb guy switching to the efi world.



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