Evo 3 16g psi with my setup help.

[pyschoslipknot]

Alight I did some searching on this question but I never really seemed to get a clear answer when it applied to my setup.
Im trying to figure out how much boost I can safely run on my evo 3 on 91-92 oct pump gas on the street and at the track?
Im thinking that since my manual boost controller has a high setting and a low setting that I'll run around 17 psi (so I'm not to hard on everthing) and then on the high setting I'll put it around 26-28ish. All while staying on pump gas. If I do that though, I dont know how I'll set it if I put in 110 oct. All ideas are welcome.
My supporting mods are:
DSMlink
6-bolt bottom end
Arp Headbolts
Eagle Rods
Wisceo Pistons- 9.0:1 compression
2g head- fresh valve job- stage 2 (street/track) port and polish
BC 272's- springs and retainers
1g valves- lifters
Balance Shafts removed
Cosmetic head gasket
255 lph
650cc injectors
Aeromotive fpr
SS fuel lines
3in turbo-back
dsmpower turbo-manifold
Intake
1g throttle body
SS Autochrome FMIC
ACT 2600
Lightweight flywheel
Koyo radiator
Greddy type rs bov
Manual Boost Controller

Please and thanks for the help.

 

[Gstclipse69]

On pump gas 26psi is too much. You'll only know how much boost you can run by looking at your timing curve to see if you have knock. With 110 you could probably get away with it but you'll just have to do a pull and tune for it. Then turn up the boost until you get knock. Ballpark I would say 23-24 psi on pump.

 

[2gGSX]

On pump gas 26psi is too much. You'll only know how much boost you can run by looking at your timing curve to see if you have knock. With 110 you could probably get away with it but you'll just have to do a pull and tune for it. Then turn up the boost until you get knock. Ballpark I would say 23-24 psi on pump.

He has Link and can actually see knock. I agree though, you most likely won't be able to do ~26 psi on straight pump gas. Get your AFR's set up and start increasing boost slowly until you begin to see knock, and you can either pull a little timing or make it a little richer and see what happens. Alternatively you could also just turn the boost down a little to avoid having to run more rich or pull timing.

The general consensus these days is that on pump gas, you should pull timing and run as much boost as you can get away with while maintaining a steady AFR. With that in mind, if you want high pump gas power then you'll have to sacrifice a lot of timing.

 

[kahl23]

Actually with DSMLink it shows knock as a function of degrees of timing pulled, which is very helpful. When tuning with DSMLink you should be mindful of the knock that you see A wideband would be very helpful too, if you have the means. We were running around 22-24 psi on the E316G on 93 pump semi-daily shooting for an AFR of around 11.8-12.0, never had any problems. This was good for 347 awhp and 357 tq, though I think the boost was creeping towards 26 psi on the dyno, but I can check. I can post our logs, if you want them.

As far as your setup, I'm not sure that the "high" setting is such a good idea on pump. Thats running the 16g fairly well outside its efficiency range, which means you start blowing hot air. That really isn't a huge problem if your intercooler can keep up with it. We ran a DV/DT Fab frontmount, which is a pretty large, thick core, and so we had few problems running higher boost. A lot has been said about the SSAC FMIC, but I'm fairly sure it wouldn't keep up with the heat at those boost levels, so you might run into issues with knock. The low boost setting should be fine.

 

[pyschoslipknot]

Yea logs would be great.
So you think I should set my low boost setting at 22-24psi and then have the high setting at 28ish (I will be able to tell after fooling around it a bit) and only switch it to high when I have 110 oct in?
What about advancing the timing. When I was searching earlier I read something about advancing the timing in higher rpms? I tried to find that thread but as luck would have it, its gone. I think one guy had 12 or so degrees advanced at redline.

 

[JayRolla]

I would set your boost at 15psi and get a good 10.8-11.1 afr. Then turn the boost up slowly keeping the afr within those limits till you get knock. Pull a little timing and add some more boost. Try to keep timing around 14-16* with as much boost as possible. You dont want to add timing on pump gas. 20-22psi is the most you will most likely get on pump gas on that turbo.

If you have e85 in your area I would look into running that. You can run as much boost as that turbo can push if you do that.

 

[kahl23]

OP- You might want to check out this thread on 16g tunes:

http://www.dsmtuners.com/forums/tun...3306-high-boost-16g-pump-gas-tunes-enter.html


I would definitely only run 25+psi on race gas. We ran 24 on 93 for a bit, but with 92-91, it's pushing it I would say, although with a good tune you could do 24 on pump. 28 is definitely out of the question on pump. As far as timing goes, we got our AFR rock solid and then started using timing advance until we saw knock, then backed off until the knock disappeared, you can see all of those values in the log. Unfortunately the only really clean log I could find was back when we were running only 22psi tapering to around 20-21psi by redline, but the timing and fuel is all the same.

Also, FWIW, we had terrible luck with 110. Immediately fouled the plugs, just not a good experience. 116, on the other hand, was a blast , never looked back to 110 after that. However, That could have just been the idiosyncrasies of the car, the night, that batch of gas, etc etc etc. I would suggest, whatever octane you run, to immediately lean out your global settings, I had used 10%, but don't quote me on that, and then take it from there until you reach the desired AFRs, then start ramping up the timing. A wideband would be a very helpful tool in this case. You should do some searching around here, and also on DSMLink User Group Forums. If you have 'link, you should definitely be a member there.

 

[gixrman]

When I was running 25psi i over ran my FIC650's and switched to 1000's. I could only do this with W/I to tune out the knock and run alittle bit more timing. Its alot of fun in the winter when the air is cold but as soon as the air temp goes up I ran into alot of heat related tunning problems and the car was noticablely slower. My best log was over 40lbs/min and 380+Hp.

 

[bastard dsm]

well the 1g dsm run a very agressive timing map,you can run 22-24psi
at 11.5af's if you pull timing down to 15deg of so.Pull to much and it becomes
a problem with egt's and can cause knock also.Instead of race gas i would
do e85 and crank the boost to 28psi or so,400hp is capable and you can
run alot of timing 20-24deg with no problem.

 

[pyschoslipknot]

Instead of race gas i would
do e85 and crank the boost to 28psi or so,400hp is capable and you can
run alot of timing 20-24deg with no problem.

Wouldnt I have to put in bigger injectors to run e85 cause isnt the basic concept just dump a whole lot more fuel in?

 

[bastard dsm]

why,you said you have 650's...i have 750's on my gvr4 and im running 28-30psi on a fp18sl2
making 445hp/434lbs on e85.just adjust your global on the link and you will be fine.

 

[Loewen21]

i find it hard to believe that you can run that much e85 on those injectors. Maybe you can pull it off but they must be pushed right to their limits. I would say since you're using link just go big and get 1200s or 1000s and be done with it.

 

[bastard dsm]

i have been doing it for a while and my injector duty cycle is under 90%,im
just saying it can be done.