afpr needed with stage 3 cal and +20's?

[duster_70]

like the title says...is there any need to get an afpr if you are running +20's with a stage 3 cal and a 3 bar map?

Seen it done a couple of different ways and wanted to see what everyone (collectivley) thought was the best route.

FYI, it is for a 90 Daytona Shelby VNT

TIA!

[tryingbe]

Install a wideband then find out if you need to lean out the fuel.

[The Pope]

to add to tryingbe's comment lol

I would also buy an OTC 2000 or 4000 off Ebay, dirt cheap scanner. Then run a test of the 02 while warmed up. If the thing is adding or pulling past 10% at idle and then at cruise the chip needs to go back or you use the AFPR to get it closer without sending the chip back.

Normally though a stage 3 doesn't need this unless you have a lot of porting and mods, it is rare with a stage 3. How ever you also mention a +20 injector and a 3 bar map, which tells me you mean stage 5, not stage 3 computer. At this level it is a good idea to have one for fine tuning, but if this is a stage 1 20 PSI build then your doing it without porting. So that type of build doesn't need much tuning, FWDperformance can hit that mark pretty easy.

[duster_70]

it is stage 3 when its a VNT SBEC from FWDP. but thank you guys for your comments! I was thinking that as well.

I did forget to mention that I have an innovate MTX-L wideband that I will be using as well to verify the A/F ratio at all times, I just wanted to know if I needed to get a AFPR as well when I install the stage 3 SBEC/+20's/3 bar MAP

[The Pope]

well with a VNT there is no real engine work done anyway, just higher boost etc.

I can't see any reason for the AFPR with the VNT, as the VE doesn't change FWD should hit that easy with no changes. I believe Cindy mentioned she has a VNT with T28 and bigger IC as well, so it may have the cal she is running.