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how much boost?
Posted: December 11th, 2011, 7:08 am
by atias
hi to all just wanted to say that this is a great site with a lot of useful information and i have learned a lot from you guys
now i have a question for some of the big guns in here
my setup is this
4.6 stroker
12 cw crank with 707 connecting rods
port and polished head include combustion chambers 7120
crane cam shaft 753905 with springs
dual headers with double 2.75 inch exhaust (stainless all)
stock deck and stock height head
sealed power pistons hypereutectic H802CP/H825CP (don't remember with one from the two but i can check)
fel-pro steel head gasket (don't remember the part number but i can check that also)
compression ratio 9.3 - 9.5 don't know really how much i enlarge the combustion chambers with the polish (but they smooth like mirror)
msd 6a ignition
28 lbs injectors with fmu(pressure regulator)
255 walbro fuel pump
colder spark plugs champion rc10yc4
ALBREX SUPERCHARGER(its like a old vortech one to one very high quality) 6 psi of boost
AIR TO WATER INTERCOOLER with radiator and water tank with 8 liters of water and bosch cobra pump
SNOW WATER METHANOL INJECTION
aem wideband and egt gauge
and i hope a didn't miss any thing else
i'm running premium fuel without detonation even on regular fuel the water methanol injection is working good and doing its job well
i have no overheating and the car is running great very very strong
i'm in the 11.5 11.3 AFR in the wideband at open throttle
egt never go past 750 celsius no matter what
now my question is how much boost can this engine take and still running safe without breaking itself (pistons rods etc)?? i want to crank up the boost
and how much horse power is it making now ?? (we don't have a dyno around here and its very expensive to check on one) (living in israel i forgot to say)
i want to upload a picture for you all but i don't know how!!!!!!!
this engine is in a jeep storm(long version of a yj wrangler)
dana 60 rear 4.10 gear
dana 44 front 4.10 gear
manual ax15 with centerforce cluch
241 transfer case
33 tires
we drive mostly on sand dunes
thank you all in advance!!!!!!!!!!!!!!!!!!!
Re: how much boost?
Posted: December 11th, 2011, 7:54 am
by atias
Re: how much boost?
Posted: December 14th, 2011, 10:51 am
by CobraMarty
How much boost are you running now?
Re: how much boost?
Posted: December 14th, 2011, 1:57 pm
by Jeep-Power
CobraMarty wrote:How much boost are you running now?
atias wrote:
ALBREX SUPERCHARGER(its like a old vortech one to one very high quality) 6 psi of boost
Re: how much boost?
Posted: December 14th, 2011, 1:58 pm
by Jeep-Power
atias wrote:
this engine is in a jeep storm(long version of a yj wrangler)
dana 60 rear 4.10 gear
dana 44 front 4.10 gear
manual ax15 with centerforce cluch
241 transfer case
33 tires
we drive mostly on sand dunes
Sorry I can't help you with the boost question.
I've never heard of a long wheelbase YJ-- pics of it, please!
Re: how much boost?
Posted: December 14th, 2011, 10:16 pm
by israelcj7
Google it"storm m240"
its an israel military jeep based on yj with longer wheelbase. different front clip and dashboard and dana 60 rearend from the factory
atias great build. love your work
keep the boost as it is.its safer to you and to your engine
i have seen this jeep in action.its a beast
Re: how much boost?
Posted: December 15th, 2011, 2:59 am
by atias
this is a old one

this one is recently
its never enough you get used to the power and it feels slow again its addictive
so that why i have to know where i'm now (horse power,torque) and what is this engine limit but on the safe side
this is a very old youtube clip the engine only got 3 psi of boost over here and i drive it in first gear high range
http://www.youtube.com/watch?v=A2DkMzPfhEM
Re: how much boost?
Posted: December 15th, 2011, 7:51 am
by Jeep-Power
wow-- that thing has some nice power.
It's hard to beat 8 lug factory axles in a YJ!
Re: how much boost?
Posted: December 15th, 2011, 7:59 am
by atias
thanks
the front end is dana 44 from a gmc vandura 4x4 (the stock dana 30 got broken every second weekend maybe 8 or 9 times)
the rear is a stock factory dana 60 with detroit locker and wheels adaptors from 5 to 8 logs
Re: how much boost?
Posted: January 4th, 2012, 1:27 pm
by TAnderson22
I built 4.7 Stroker motor less the supercharger..... and built it with option to upgrade to turbo once I felt the brakes and suspension will perform well enough to allow it.
I also have built and stroked many subaru turbo gasoline engines, and have much experience with turbo diesel tech. I have manufacturer certification for many over the road turbo diesel engines.
As long as your knock sensor works, you are likely safe to 8-10 psi but take it in small steps if you don't have an electronic controller for the pressure.
I would suggest the following:
#1) LOOSE THE CHAMPION PLUGS before you cause a detonation problem and ruin that motor. I know they were the OEM choice, but NGK, Denso or AC is the best and don't wear out in 3,000 miles or less. Avoid HC attracting platinums, go to iridium, it is a PGM, but it does not trap HC because of it's valence charge. Platinum is great for converters, bad for plugs, no matter what marketing tells ya. iridium provides no catalytic effect.
#2) You are probably not having any detonation problems because you are running TOO rich in the 11's. Stochiometricy with gasoline is 14.6:1. You have a nice wide band gauge, but you can't control the fuel delivery, so your only watching it. (If you don't understand stochiometricy, the gauge is useless to you, evenmoreso if you can't control the fuel input!) Get a quality injector pulse width controller like APEXI makes. Don't screw with the ECM pressure sensor input - garbage in, garbage out is basic computer knowledge. You might want to visit some rice rocket sites to get some help with turbo and other aspiration questions that will not come up here. Watch that EGT gauge that's nice to have and is key too - if it gets too hot you need to add fuel to quench the heat before you melt. The length of the hydrocarbon chains in premium fuel also is important- so don't use anything less! The octane rating is needed to keep the fuel from exploding under compression (as diesel does) but your low compression ratio for a turbo/super (IMHO) is helping you not ignite here (and prob why it runs on regular)(deck should have been milled ).
#3) Up your injectors to at least 30lb/hr - I found that I don't need to increase the FP from stock with the correct sized injectors, and additionally, the need to modify the pulse width of the delivery was nullified. More volume/flow is better than longer injector on time or higher delivery pressures to band-aid it though. Better to be able to deliver too much and feather it off, than be running 100% dwell and still be short on fuel. All emission computers are programmed to find stochiometricy no matter what injector it is firing into any displacement motor. Investing in a fuel pressure gauge (mounted) will also tip you off to >VOLUME DELIVERY< problems no one ever thinks of on these boards.
#4 - GO ISRAEL!
Re: how much boost?
Posted: January 4th, 2012, 4:06 pm
by atias
thank for the reply
just a few things i have to correct
i don't have a knock sensor, its obd1 without knock sensor and no o2 sensor, its like that from the factory
its a old military jeep, its runs on OPEN LOOP the all time
#1) the champion plug that i'm using are a two steps colder then the OEM (OEM are RC12)i'm using rc10 gapped at 0.30
and i also read on procharger site not to use any point type sparkplugs with the supercharger because
the needle center electrode becomes a hot spot that can create detonation and pre ignition
they say to use copper plugs recommended
#2) about the fuel, i'm running premium plus water methanol injection, my AFR is 12.5 at WOT without the
water methanol injection! once i turn it on its 11.5, i'm using 50:50 mix
my next goal is to get the split second ftc1 to control the fuel and spark timing,
#3)the injectors i'm running are 28 lbs, not far from 30 but until ill get that FTC1 to control the fuel on
idle and cruising, i cant put on a larger injector because its already running a little rich
#4)thanks alot from me (and israel)
my only concern are the pistons they are hypersomething with high silicon content and i had been told that they are
brittle under high load
and thanks again for the reply i'm appreciating any bit of knowledge i can get

Re: how much boost?
Posted: February 13th, 2012, 2:53 pm
by TAnderson22
Interesting... I need to modify statements based on this new information.
I understand why you are running so rich with that Open-Loop setup...that is tough to correct w/o some big time changes! lol! Not having a knock sensor sucks and that is a hard one to fix for the same reason. However - NOT having that closed-loop control is going to be good for your piggyback mods to the electrical - since the jeeps is not already "controlled" by the main ECU/
That is an interesting point about the plug type, and a heat problem I never considered. I'm going to keep this in mind. I will say, however, I am a huge fan of copper plugs where you can use 'em. They work better, they just wear quicker. I'm still going to rec the NGK vs. Champs. In my experience the Champ plug just doesn't last. I worked for a Jeep-specific shop and we did not install them for this reason and they preferred AC delco. My own experience is go japanese.
Hyperelutic (sp?) pistons? Yes they are brittle n can rattle when cold. Otherwise they shouldn't be giving you any issues.
I think that the root of your economy problem is that military open-loop computer.
The best part about it is you are on the rich side; you would be hurting if you were stuck lean.
I believe you are going to find your best help with the piggyback spark and fuel control. then you could adjust your fuel output and watch it on your wide band. With those tools you can really monitor what is going on, which gives you the ability to see when too much boost... may be too much! and have the ability to do something about the mixture other than watch. .
Hope that can help!
Re: how much boost?
Posted: February 13th, 2012, 5:08 pm
by SilverXJ
TAnderson22 wrote:Hyperelutic (sp?) pistons? Yes they are brittle n can rattle when cold. Otherwise they shouldn't be giving you any issues.
Yes, hypers are brittle, but if installed with the correct piston to bore clearance they won't rattle when cold.
Re: how much boost?
Posted: February 13th, 2012, 10:53 pm
by Muad'Dib
Mine do not rattle i know that...

Re: how much boost?
Posted: February 14th, 2012, 4:11 am
by atias
some new updates
got the aem fic up and running and working great after i worked out a few bugs.
apparently my boost gauge is a piece of $h1t

i'm getting a 8-9 psi of boost reading thru the fic

so i'm not changing any pulleys soon
backed up the igniton timing a little bit!
from what have read the NGK plugs are way better then the champion and preferred by alot of racers , i will change to them the next time
still waiting on some big injectors
i don't hear any rattle from the pistons the only noise i have from the engine is a little valve ticking from the CRANE camshaft.
i was more afraid from the load i'm putting on them
thanks for the reply ,much appreciated.
how much estimated horse power and torque do you guys think this setup is producing with a good tune
and thank you all for helping me out. hope i can help out too in the nearest future
