I ran my tank to almost empty and then drained out the last of the 93 and put in some VP104. I was expecting to be able to raise my boost from 21 to 24 or so and add a couple degrees of timing on top of that. Well, the best I seem to do without knock is about 1 psi more and about 1 degree more timing According to my Blitz Powermeter (which seems fairly accurate from a relative standpoint) I'm gaining only about 18 peak whp and my Karman readings are only about 100 hz higher (peaking at a little over 2000 in 2nd gear and about 1970 or so in 3rd and 4th gear).

I was hoping for more like an extra 30-40 whp, but I guess not. I'm thinking that maybe I'd get better results with alky injection than this 104 unleaded. It doesn't even seem worth it.

Do my results sound right, or does this sound more like a false knock issue? Would I get the results I'm looking for with alky injection or C16?

My timing looks about like this on 104:

5500 8.5
5750 10.5
6000 12.5
6250 14.2
6500 16.0
6750 17.5
7000 19.0
7250 20.5
7500 20.5

And I'm keeping AFR in the 11.2-11.4 range.

Any suggestions appreciated.

 

the afr is fine, but try more boost but lower timing. Lower the timing and set the boost first, then try adding timing after that.

 

Okay, just went out again and tried your suggestion. Dropped timing 2 degrees from about 5750 up and then upped the boost about 1.5 psi. The car didn't pick up any noticeable peak power, but there was a significant gain in the logs on power/airflow in the 5000-6500 range. It felt like it was accelerating faster too, so I think you steered me in the right direction. Thanks.

 

no problem

 

How u like that UTEC??? Sorry for the OFF TOPIC question

 

At a given AFR, say....11.5, which is better for power gains.....more boost or more timing?

 

combo of both

 

I though u can lean out 2 around 12.0? or is that with 116 oct?

 

ok. Another question

20psi with lots of timing or .....24psi with lesser timing?

 

104 octane will almost definitely make less power than Alcohol Injection.

I typically see 10-15 whp on 104 octane.

20-30 whp with Alcohol injection.

30-45 whp I still see the highest gains with C16.

These are stock turbo number.

Thanks,
Jermaine

 

I can't say I'm glad to see that 104 isn't what I thought it would be, but I'm glad to know that what I'm finding isn't atypical.

I'm confused by your last two ranges. You are saying 20-30 with alcohol or c116 and 30-45 with c16? c16 is 116 octane right?

Did you mean 20-30 with alcohol and 30-45 with c16?

Thanks.

 

Right that's

20 to 30 whp with alcohol.
30 to 45 with C16 which is 117 octane.

 

C16 is closer to 118 octane.

 

C16 - R+M/2 = 117

 

Where will 100% water injection be?