Forced Induction, keep reliability while adding more boost, less timing? Pull up a chair..

FoxMustangLvr

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My car runs great and has great power and I'm very happy with it. Still I get to thinking, can I somehow keep the reliability of my supercharged 5.0 while increasing PSI? I have the itch to increase boost a little bit, say from 11psi to about 14psi. In doing so I'd pull some timing out to make it safer (detonation). Does a few degrees less timing and a few more PSI seem a logical and safe approach? Would I end up with more power or about the same? One thing is for sure, I would not actually move forward with this until I installed my ProMeth kit. I should've already had it in as it is. My Kenne Bell 2.1L Flowzilla efficiency range I believe is from 10-18psi so I'd be right in the middle.

Your thoughts please......... @90sickfox @a91what @TOOLOW91 @Noobz347 who else is boosted on Stangnet? Not many I think.

Some things I've read lately about being safe in boost with our SBF's is to limit rpm, keep timing conservative, keep a safe AFR and things should stay together.
 
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a91what

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If you are adding the Wmeth you probably wont need to touch the timing curve at all. can you post a copy of the timing curve for me to see again?? I remember helping you with it but i purged my back log of tune files.
 

Noobz347

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If you currently have a method of reading and data logging your air fuel ratio, then I don't see why not. If it starts getting choppy anywhere then back it on down.

I have a couple of pulleys hanging on my wall. I'll measure them when I get home and you can tell me if you have an interest. I would loan them to you for testing.

PD blowers hit pistons pretty hard but they're otherwise, pretty gentle on the block and crank.

You already know what your block limits are.
 

Noobz347

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If you are adding the Wmeth you probably wont need to touch the timing curve at all. can you post a copy of the timing curve for me to see again?? I remember helping you with it but i purged my back log of tune files.
Even without meth, you shouldn't really have to touch the timing curve. If it was done correctly initially and the blower is not being pushed outside of the efficiency range, and there is no shortage of fuel then adding a little more boost shouldn't effect anything. It will continue to retard timing appropriately.

The reason I have all of those pulleys to begin with is because I would change them seasonally. NO other mods. Took me all of 2 minutes using a breaker bar to hold the tnesioner.

When adding the meth the timing curve needs adjustment specifically [for] the meth.
 

a91what

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Even without meth, you shouldn't really have to touch the timing curve. If it was done correctly initially and the blower is not being pushed outside of the efficiency range, and there is no shortage of fuel then adding a little more boost shouldn't effect anything. It will continue to retard timing appropriately.

The reason I have all of those pulleys to begin with is because I would change them seasonally. NO other mods. Took me all of 2 minutes using a breaker bar to hold the tnesioner.

When adding the meth the timing curve needs adjustment specifically [for] the meth.
never hurts to verify, I remember having to sort a mess out from when he had this car "tuned" lol
 

a91what

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If you currently have a method of reading and data logging your air fuel ratio, then I don't see why not. If it starts getting choppy anywhere then back it on down.

I have a couple of pulleys hanging on my wall. I'll measure them when I get home and you can tell me if you have an interest. I would loan them to you for testing.

PD blowers hit pistons pretty hard but they're otherwise, pretty gentle on the block and crank.

You already know what your block limits are.
thats pretty cool willing to loan the pullies out.

It's not that it never hurts, it is [required] IMO. That's why I specified:
we are completely in agreement then, better safe than sorry.
 

Noobz347

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I look at it something like this:

If you tune a car for boost then the outcome of that tune should be linear. If that is true, then increasing boost by a few lbs is nothing more than opening up the throttle earlier in the RPM range. A good tune shouldn't be phased by a little more boost. It will still command the same mixture of air/fuel/ignition given the mass of air ingested. As volume rises, timing diminishes etc...

As soon as you throw something like water/meth into the mix (or anything that displaces fuel/air) [then] the mixture requires attention in order to take advantage of all of the additional timing you can run. Without it, the overall net power result can be a loss (not usually due to the small quantities injected). Some mechanism whether electronic or mechanical must be used to see the full benefit of water/meth. For us, the simple method is tuning. A normal N/A EEC or tune doesn't know it's being sprayed or what to make of those conditions. We can ball-park the nozzle size and take care of the details through EEC.

Before FI, you had to precisely adjust air, fuel, and water/meth, all through their respective mechanical adjustments. Tuning for just that one property through FI, is considerably easier. lol Isn't technology grand? :D


I have considered many times, installing water/meth on my combo and I still want to however (comma), in order to do it right, we would need to machine a boss into the pressurized intake to accept a nozzle that will sit down into the air stream. Injecting before the blower is just not an option for me. Another thought that I had was make a plate to go between the blower and upper plenum. This has the added benefit creating more clearance for valve covers. The downside is that the accessory bracket for the KB needs to be modified to accommodate the height of the plate. Not an impossible task. I even think that there's a template floating around on KBs site for modifying the bracket for use with a KB over the top of TFS heads. So long as the plate was 3/8 inch, the template should work perfectly.
 

a91what

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Well that depends on how far out the scaling was done, on a MAF car your thought is spot on. The tuning on the car in question was done in speed density... not an issue if they scaled it properly, but from what i have seen lately the likely hood is low..:O_o:

After some reading i do agree on the post blower nozzle arrangement, this is how i will be doing mine.
 

FoxMustangLvr

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I datalog through my Stinger Pimp ECU and my tune is pretty well dialed in and "safe". With more timing and more boost doesn't my cylinder pressure increase? Wouldn't that increase the chances of detonation? This is my reasoning for pulling timing out if I increase boost.

@Noobz347 Thanks for the offer to loan me pullies. I have a friend close by that I can grab some from if I need them but I will be leaving my existing 2.75" pulley alone, i'll add more PSI by adding a 6.5" F-150 pulley. I need all the belt rap I can get on my snout since I'm 6 rib. This will probably require me to run U/D pulley's.
 
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FoxMustangLvr

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Regarding meth injection, I'll add a 14gph nozzle to my 2" Accufab TB spacer. I'll tap a couple holes because likely, from what I hear, the 14gph won't be enough especially if I increase PSI. Likely I'll run (2) 10gph nozzles (but I'll start with the 14gph first).
 

FoxMustangLvr

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I suggest tapping the outlet from the blower, then start with one 10gph nozzle
I've heard mixed reviews about doing this however most peoples results vary even if their combos are very similar. Many people have run nozzles in the TB, inlet, and discharge and most report the discharge location didn't change anything. Best results were pre-blower. I will start there and if the results aren't that good I'll tap in to the discharge.
 

FastDriver

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Seems like the tuners I've spoken too typically want to see 20+ rwhp per lbs of boost from turbos, and once they don't see that anymore, they don't keep going. Then they adjust timing and watch the response on the dyno or verify with plugs.

I don't know how this carries over to PD blowers.
 

Noobz347

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Seems like the tuners I've spoken too typically want to see 20+ rwhp per lbs of boost from turbos, and once they don't see that anymore, they don't keep going. Then they adjust timing and watch the response on the dyno or verify with plugs.

I don't know how this carries over to PD blowers.

Not perfectly but similarly. There reaches a point where blower exhaust temp rises and causes returns in HP to diminish. That's the 'efficiency rage' FoxMustang mentioned earlier. Over spinning is not a good thing and the usable portion outside of the efficiency range is much narrower than on a turbo. hehe
 

TOOLOW91

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I’m late to the party . Adding the meth you could keep it the way it is or even get after it a little more . With that said you’re now relying on the meth here . Taking to much timing it to play it safe can also Be no good and lift a ring land to my understanding .