Curious, if a turbo restrictor is mandatory, and boost is limited, is there any reason why you’d want the 10.5 hotside vs the 9.8? My understanding is that smaller exhaust housing should be a little more responsive. Does that make sense or is there a benefit to having the 10.5 even if the flow is restricted on the compressor side? Planning on adding sas hardware and some antilag, but current power drops off around 5.5k with the 10.5

 

IIRC on a normal setup, I believe there is a 20-40 whp difference on E85, so it is worth the tiny extra lag (if even noticable) to go with 10.5.

 

And I don't see how antilag will help on a tiny turbo. I only see that with antilag, you will overboost and have some serious boost spikes on spoolup.

 

Isn’t that difference in power in the upper rpm range? With the 36mm restrictor, power drops off big time above 5k (my 10.5, where the turbo would be more efficient.)
After listening to a bumper mounted video from a high speed stage rally, it was obvious how much time it took to make actual boost over a given run (even though I knew my throttle actuation was like a WOT on/off switch.). It’s a significant amount of time, even with the “ tiny turbo”.
In the interest of making the Turbo spool as quickly as possible, the small hot side makes the most sense, was just looking for some reasons I may not be considering regarding antilag in practice as opposed to in theory.

 

The compressor of a restricted 16G will "max out" way before the 9.8 exhaust housing. The only benefit I can imagine for the 10.5 is keeping EGTs down if you're anti-lagging the heck out of it, otherwise it's just going to hurt response a bit.

 

My bad, I didn't pay attention to restrictor part. Restrictor is way small and it will kill power. I agree with RS200 that benefit of 10.5 is less back pressure up top to help lower temps. So you can probably run a little more boost with that cushion over 9.8.

 

How often are you changing your turbo with antilag?

 

Just starting putting it together, so still on original turbo. Sas hardware should be here this week, may be a while before I get it tuned/working depending on what off throttle parameters the factory ecu has available.
Doesn’t seem like much based on what I’ve read, so I may have to get an EMS. Came across a cheap 9.8 turbo/manifold all together (thinking about building my spare setup) and wanted to get feedback about potential problems with the 9.8

plan is to setup speed density immediately and run the sas full time as a bov. Depending on off throttle enrichment and whatever parameters can be messed with in those conditions, I’ll work on tuning the antilag. From all the rally articles I’m seeing, it’s no where near as destructive as most people think.

 

*laughs in antilag* 😂😂

Been there done that. You're not wasting your time but you're not going to get the kind of results you are thinking.

 

This because of the ecu? How successful was your setup?