Would I benefit from a larger lid?
08-11-2015, 02:19 PM
#1
Would I benefit from a larger lid? I've received a recommendation to upgrade my Fast Toys lid from 85mm to 104mm for additional performance. I'd like to know who has upgraded from a smaller lid to the 104 (without changing any other parts) and what proven differences you noticed other than a lighter wallet. Thanks!
08-11-2015, 04:44 PM
#2
Looking at your combo it appears you do have a larger MAF but going into a 92mm tb and ls3 intake?
Do you have access to a scanning software? If so turn the key on engine off and record the MAP sensor pressure reading in ambient air. Then do some WOT pulls and see what it is. For good measure you could then remove the lid entirely (if you can find something to support the MAF) and see what it is without the restriction of the lid.
FWIW most setups seem to be within 1-2 kPa of ambient air at WOT. If yours are within that range I would not expect to gain anything with the lid swap. If yours is higher than that with the lid but removing the lid drops it, you will see some gains.
Do you have access to a scanning software? If so turn the key on engine off and record the MAP sensor pressure reading in ambient air. Then do some WOT pulls and see what it is. For good measure you could then remove the lid entirely (if you can find something to support the MAF) and see what it is without the restriction of the lid.
FWIW most setups seem to be within 1-2 kPa of ambient air at WOT. If yours are within that range I would not expect to gain anything with the lid swap. If yours is higher than that with the lid but removing the lid drops it, you will see some gains.
08-11-2015, 05:47 PM
#3
Yes, I have HPT. Here's a partial log from this past June where I intentionally exaggerated the scaling of the Barometer vs MAP to make it easier to interpret. I didn't take measurements without the lid, but it shouldn't be a problem to stabilize the MAF (which has a Saxon flow straightener in it) in my current setup. Do you think I should try it w/o the lid, or is there enough shown here to say do it?
08-11-2015, 08:29 PM
#6
Yes, I have HPT. Here's a partial log from this past June where I intentionally exaggerated the scaling of the Barometer vs MAP to make it easier to interpret. I didn't take measurements without the lid, but it shouldn't be a problem to stabilize the MAF (which has a Saxon flow straightener in it) in my current setup. Do you think I should try it w/o the lid, or is there enough shown here to say do it?
Thats not even at the top of the pull so it may be even worse in a few hundred more rpm
08-11-2015, 10:44 PM
#7
Even though the cursor is not at the peak RPM of the pull, you can see the top of the pull, the ambient is 103kPa through the entire pull and the MAP is bouncing between mid-to-upper 90's kPa at the top end of the pull before it hits the limiter. I think I'll try one.
