does anyone kno the compression ratio of the f22 bottom end
i am puttin on a h22 head and i want to run 17 psi with the turbo and i heard the bottom end will with stand 10000 rpm and the top end will only hold 6500 is this true

 

LOL. I dunno where you got this info from but whoever you heard this from you need to stop listening to them. The F22A comp ratio should be 8.8:1. When its mixed with the H22A head i dunno what it is. All i know is that its a lil higher.

 

so what rpm would the stock pistons and rods b safe at

 

My F22A6 redlined like at 6300. The H22A redlines around 7200 or 7400. Why dont you strap on an H23 head onto the F22 block?

 

i have a h22 ready for me but im goin to replace all the springs retainers valves to titanium and steel so thelly prolly go to 10 grand
but the bottom end has to b stronger than 6300 because its usually the top end thas weaj not the bottom
and it is an open deck so that could b a reason too

 

No more then 7k . the f22 has to long a stroke to rev any higher.The H22 bottom end can handle much higher revs.But if you run 17 psi of boost then you will have problems,,
Some people say you have to sleeve the h22 some don't.So it's a toss up as to what the truth is on that one.

But the F22 can handle lots O boost with the stock block.anything over 10psi and you'll need forged pistons and rods though.

Just remember to set Vtec to 34000.0098:^.3 Mhz and you'll be fine.

 

As an example, the '97 F22B1 and 2 both share an 8.8:1 compression ratio. This is the sum total of the combined effects of the Cylinder Head's Combustion Chamber Volume and the Piston Dome configuration.
Because of the lightweight valve train and the rotating masses of the crank & rods, I could see an F22 at 6500rpm all day long. It could probably live at 7000 if it had to, but it's on the wrong side of the power curve at that point.

P

 

how do u set the vtec

 

People can Flame if they want I'm just thinking this out in my head.

With the longer stroke of the f22 if you rev past 6500-7000 the dwell time at tdc {were the engine has compression and makes it's power each stroke}
You will loose efficiancy and power any way because each cylinder is on the up and down stroke most of the time spends less and less time at TDC.??

Is this the right way to think of it?

 

I was just kidding about the vtec thing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dmc1 &raquo;</TD></TR><TR><TD CLASS="quote">
Just remember to set Vtec to 34000.0098:^.3 Mhz and you'll be fine. </TD></TR></TABLE>

LOL, you can be such a &*^% !! sometimes (just funnin' with ya)

What sets the speed limit down below has more to do with angular velocity and Piston speed rather than tdc loitering time. Theoretically, the longer stroke accelerates the piston faster since it has to travel furthur (in the same amount of time) as it's short stroke cousin; and spends less time at tdc. That's the trade-off with long-stroke design: better bottom-end torque production (from better mechanical advantage) but an RPM limit as to not overstress piston pins and other sundry bits and pieces.
The power curve is determined more by breathing events and efficiencies.
High lift, short duration cams develop gobs of torque at the low end, but quickly runs out of wind upstairs. Conversely, High lift - long duration cams develop oodles of horsepower upstairs but at the expense of torque on the bottom.

P