Wondering if I have a pg turbo running 100% av gas would I run out of octane before max duty cycle on injectors and fuel pump? I would be mostly 4000-8000ft. What do u think the max boost pressure would be safely. It would be on a 11 m8 and reason I ask is I don't want to run rg no problem with av just don't think I will gain a whole lot with secondary injectors unless I run better fuel. More fuel same octane to me doesn't equal more boost and if my fuel maxs out before my injectors is there any point in complicating the system with more injectors. By the way is a timing key to save your bacon because you forgot to turn the boost down on your way to the truck cause I see people adding them but if you are retarding your timing you make less hp so u don't deto but up at elevation you shouldn't need it and if you think that because of the timing key you can add more boost you can but I would think you r making less hp. So if your at say 12 psi then the key retards your timing you would make the same numbers at lower boost without the key correct? I have more questions but I think I'll hold off for awhile. I am new to turbos as you can tell just trying to wrap my head around it before I buy my first kit thanks for your input it appreciated.
Pg question
- Thread starter vans411
- Start date
Thought there would be someone with some answers guess everyone is playin to bad I have to work. Simply put is there any point in buying a rg kit if I won't run rg and ride from 4000-8000 ft
K
kcdavidak
Well-known member
i'am by no means an expert but I did start out exactly where you're at wanting to run pg kit and get all I could out of it. if you're willing to run av/100ll then might as well pony up for extra injectors cause you'll never be happy with 7-8lbs .you'll run out of injectors before octane with 100ll ,you won't det but injectors will be maxed,been there done that. and depending on the kit you'll never see that 12lbs you seek. I run 12lbs sealevel literally I can see it out my front window here to 3000 ,above 5000 mix 50/50 12lbs ,09 head no timing key. if your willing to run the right gas then timing key is a waste.
Pg kit
My buddy has a 2010 m8 with a boondocker pump gas kit, running a water to air intercooler and a 3 deg timing key. Stock 2010 head
Max boost he runs is 9 psi, bumps it up to 10 and will hit det sensor on a long pull. Maxes out injectors with stock fuel pump
Running 94 oct. with about 25% av.
4-7000 feet
Stock injectors
I'm running a 2011 with a cutler stage 2. 2009 head no intercooler, no timing key running 9-11 lbs boost. The cutler stage 2 kit come with a bigger fuel pump and you can adjust your fuel pressure.
Running 50% 94 oct. 50% av.
4-7000 feet
Stock injectors
These are our findings hope it helps
Gongshow
My buddy has a 2010 m8 with a boondocker pump gas kit, running a water to air intercooler and a 3 deg timing key. Stock 2010 head
Max boost he runs is 9 psi, bumps it up to 10 and will hit det sensor on a long pull. Maxes out injectors with stock fuel pump
Running 94 oct. with about 25% av.
4-7000 feet
Stock injectors
I'm running a 2011 with a cutler stage 2. 2009 head no intercooler, no timing key running 9-11 lbs boost. The cutler stage 2 kit come with a bigger fuel pump and you can adjust your fuel pressure.
Running 50% 94 oct. 50% av.
4-7000 feet
Stock injectors
These are our findings hope it helps
Gongshow
Thanks for the info it's helping
I have a 2010 MB with a BDPG kit. Here's my take: If you're going to be running straight AV get a RG kit. I start at around 7500 ft and the injectors max out at around 9 lbs of boost (less if under a lot of load. I'll max the duty cycle at around 8 lbs if I've got my girlfriend on the front.) I'm running 2 gallons of 111 per tank and don't hit DET.
M
M1000Mod162
Well-known member
Seems odd to me. I have a 2010 m8 with pg kit and Im running straight av at 9-11,000 feet. I hit det any time I go over 8.5lbs boost unless Im above 10,000 Ive found! Ive even been adding a splash of rg 2 1/2 gals to go for 9 lbs running about 85-93 dc out! This is with stock motor stock head stock timing! Ive talked to Jarred S at bd and he said this was normal with stock head and no timing! He said with timing key and intercooler I could run 9lbs on good 91 octane at my elevation!
I personally dont see the need to do anything to it Except maybe a timing module so I can run some pg! I was thinking secondary injectors when I first got the sled but now im not thinking so! I pretty much need straight rg to max the kit out the way its set and it runs as good or better then all the rg kits ive rode with this year so far so.....my 2 cents
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I will keep this simple for you
the stock a/c injectors will max out at about 200-210HP with avgas. a 4 injector turbo system will put out about 250-260 HP. timing keys are worthless if you are running higher boost with good fuel. a timing key will retard power in which you lose HP. ex. If you are climbing a steep hill do you want your timing key to retard your power output or do you want your engine running at maximum as you crest the steep and deep.
the stock a/c injectors will max out at about 200-210HP with avgas. a 4 injector turbo system will put out about 250-260 HP. timing keys are worthless if you are running higher boost with good fuel. a timing key will retard power in which you lose HP. ex. If you are climbing a steep hill do you want your timing key to retard your power output or do you want your engine running at maximum as you crest the steep and deep.
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m8lovin
Active member
M-head your running more than enough octane for that boost. On my 07 twisted m8 i have ran 13.5# on straight 100ll at 6000' with no det. If your wanting To run 9.5# you should be able safely run 70% av to 30% 91 pump. Saves money and throttle response is much better. Just my .02
I had good help with my 10 hcr the BD pg and i was able to run 10 psi mixing 2 gal of 110rg with 91. i have the 09 head. i was at about 87out on my duty. and i was having a blast. i was at about 10k
M
M1000Mod162
Well-known member
A 09 head also takes away Hp similar to a timing key! People do it so they dont need as much octane because you cant run straight pump gas in it safely! But I have seen already that the 10-11 ho head makes same power as a 09 head does with 2-3 lbs less boost yet needing the same octane or more! So with a 10 or 11 ho stock head and motor we can make as much power on stock fuel system (8-9lbs) as guys with 09 head and 4 injector setups do at 10-12 lbs! Thats my take Im surounded by turbo sleds and we compare alot! Not to mention I keep charge temps cooler running lower boost numbers!
Btw to make 250-260 hp I believe you will need straight rg which this guy does not want to do!
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