does anybody have any experience with a higher compression motor like 10.5 or 11:1 compression and boosting with say t3/t4 or smaller turbo? i have a block that has all forged bottom end and the compression is around there and i want to boost. does anyone have any experience with 11:1 and 10psi???
Im preety sure the AMS evo runs about 10.5:1 compression ratio. but i also belive they use the Direct inject fuel system on it.
You might be ok as long as you keep the boost low and get it properly tunned
that is VERY high and will need a very careful tune on the highest octane you can find.
Couldn’t you use some sort of water or methanol injection to fight detonation.:think:
I was about to post that just now… over 10:1 compression I reccomend water injection. Cheap, will reduce chances of detonation drastically but will complicate your tunning and setup. I’d say its worth it.
I’m having a hard time understanding that 10.5 is VERY high. maybe 11, but 10.5 is 0.1 lower then the stock JDM GSR motor. and I’ve seen people buy them, install them and boost them without touching the motor internally. And they run 12’s at 8psi. but I’m thinkin that if i forge the internals i can run 8 more reliably or 10 at the track. when people boost GSR’s and B16’s with stock blocks nobody says that the compression is too high for boost. but when i talk about building a turbo motor with the same compression (little lower actually) people get REAL cautious and warn me about it.
with that being said, is everyone still concerned with 10.5:1 at 8-10psi with t3/t4 turbo???
EDIT: i am not trying to prove anyone wrong. i want this to be a long lasting discussion so i can learn as much as possible before finishing this.
i found this as an example:
CAR MADE 279whp@8psi and 194ft/lbs it is fully tuned by Dan at Godspeed inc. full throttle and part throttle/street tuning
thats on a stock GSR motor:
11:1 on a b16. pistons and rods only. stock headgasket. 18g greddy kit on 10 lbs. tuned on uberdata. pump gas. very reliable IMO. started everyday for me and is still running to this day. No detonation problems whatsoever. Thorough tuning is key
thank you. How quick is it? is this in a DA?
i have hondata S100 installed on a P28 and theres a pretty reputable hondata tuner that lives right near me. i’ve never heard anything bad about him, just great things.
The Audi TT circuit car runs like 11:1
who else has built a setup like this though?
Two years ago I had a built ls/vtec. Forged rods, forged pistons running 11:1 compression with a custom built T3 super 60 setup. Fully dyno tuned using chrome and my engine detonated after awhile. Melted the pistons.
I would HIGHLY SUGGEST getting some form of knock control (J&S safeguard) into your setup as DA’s do not have knock sensors.
To this day neither the builder, tuner, or machine shop have any idea why my motor detonated since I took all precautions in the build and in the tune and on the street.
10psi, very conservative tune (yet still blew up) made 200hp to the wheels.
-Rik
[QUOTE=Rikter;1680202]Two years ago I had a built ls/vtec. Forged rods, forged pistons running 11:1 compression with a custom built T3 super 60 setup. Fully dyno tuned using chrome and my engine detonated after awhile. Melted the pistons.
I would HIGHLY SUGGEST getting some form of knock control (J&S safeguard) into your setup as DA’s do not have knock sensors.
To this day neither the builder, tuner, or machine shop have any idea why my motor detonated since I took all precautions in the build and in the tune and on the street.
10psi, very conservative tune (yet still blew up) made 200hp to the wheels.
-Rik[/QUOTE]
well thats disappointing! who the hell tuned it? any honda motor with a stock block at 10 psi would probably make more then 200whp. why would a built one with forged rods and higher compression make only 200?!!?
Imagine if you would have done the exact same setup but with a completely stock JDM GSR motor at 10.6:1? would u expect the same results? does the .4:1 compression make that much of a difference?
Because it was my first foray into the world of forced induction I asked the tuner to make sure it was a conservative tune. It was done on a dyno by a company that has been tuning all sorts of makes of cars on all sorts of platforms (chrome, aem ems, hondata, etc). Fully qualified to tune cars. I was very happy with the 200hp (remember, this is measured at the wheels, not crank) through my B16 Trans. Car ripped. Unfortunately it ripped itself apart.
With more time and more time on the dyno it could have gotten much more power out of it to be sure but at the time I was content.
-Rik
…?
its doable… you just need a good tuner… look at all these turbo K guys… stock K-series motors are 11:1 compression. I actually had a friend that was running 12:1 compression and boosting. Only real problem was that he had to run race gas all the time… he eventually blew the motor tho cuz of a bad boost spike
i mean. i want to build a 12 second integra. thats reliable and street legal. i think at 12psi with 10.5:1 with forged internals, a t3/t4, and a good tune should get me there. and a boost controller and 5psi spring so i can run the thing around at low boost when im just fartin around.
of coarse i will need some track time and tires, but im only talking about what is needed in terms of engine setup…
what motor are you running?
You can run 12’s all day long with a stock b18c at 10psi and drag radials…
[QUOTE=SweetChin;1681016]what motor are you running?
You can run 12’s all day long with a stock b18c at 10psi and drag radials…[/QUOTE]
i have a JDM B18C (GSR). right now it has 10.2:1 compression (real close to USDM compression). all forged bottom end, and im wanting to get it sleeved and re-assembled by a professional. The person that put it together the first time wasn’t reputable. and i decided to have it sleeved, i figured i’d do it all right before dropping it in my integra.
so i figure that setup at 12psi should be straight. but i was considering upping the compression a little and lowering the boost while i was rebuilding…
not sure though. thats what this thread is for.
here is a friend of mine with a stock b16a2 on 10psi.
http://www.502streetscene.net/videos/video.php?v_id=230