I'm not going to do anything, just curious........

What do people do to engines able to handle higher revs?

Obviously the rev limiter is removed first, but then i guess there are certain internals that needs to be replaced.

What are these certain pieces?

Thanks,
Victor

 

Well, you'll have to have the appropriate valvetrain to accomodate high revs so you don't float the valves, higher compression pistons always helps, and a lot of tuning... there's more that goes into the equation, but that's a basic start...

 

You also have to worry about hitting the next harmonic of the driveshaft (or other parts) as you increase RPM. I have heard of needing friction-based dampeners that are much more complicated than a two-part pulley.
--
Jeff

 

Higher strength valve springs and titanium retainers really help and allow the higher revs. The biggest issue with higher rpm's is the mass of the valvetrain components. With really high rpm's a full titanium valvetrain (retainers,valves,etc) is critical to keep everything running right.

 

The real key for high revs is the bottom end, this is my recipe for an older style engine. This is my scenario

1 engine block that can handle high HP (1 Bowtie block 4 bolt main splayed main caps
2 Forged steel crank shaft
3 Aluminum rods
4 Forged KB 13.5.1 CR Pistons
5 The best fasteners money can buy, I have everything studded into the bock

Basically high strength lightweight rotating mass, of course there is alot more to it...this engine has seen 9200 RPM by accident on several occasions and has made over 200 passes through the 1/4 with a best that is in my sig. and is still in one piece...Who says V8's can't rev...

 

^^

Do you mean forged aluminum rods?

 

Good rod to stroke ratio, oversquare block, light crank and flywheel, (F1 cars have about 6" flywheel), straight intake track, lightweight valvetrain, large wiping pads for the cams, strong springs, adjustable timing and lift, etc.

 

Yes Forged aluminum BME rods, again there is alot more to it but my receipe is a good foundation to start with, but it is costly...

 

Do you have to go to high compression to achieve high revs? I wonder how much the redline in the Z could be increased if you stay with 93-94 octane.
--
Jeff

 

The compression of the engine has nothing to do with the amount of RPM's it will handle before something breaks.

A low compression blower motor will rev just as happy as a 14:1 race motor. You want to lower the mass of the rotating assembly and control the valves from going into valve float. All the needed parts have been spoken of by others. I think Honda use titanium rods in the NSX to rev the engine higher. Things that like to let go at high RPM's are rod bolts. Using aluminum rods in a street motor is not the best idea, they will distort over time. But if you are willing to change them out yearly then it's only $$$$.

Also then you have to figure out a way to keep the air flowing into the cylinder. Open up the intake ports and valves to flow the air the engine wants at the high RPM's. Then you loose low end, where you spend most of the time on the street. And a lighten flywheel only make it worst to drive on the street

In the end you would end up with a very high strung buzzy engine wanting to live up in the high RPM's and a lazy dog off the light.

 

The Z retainers are already lighter than titanium ones ,they are 2024 aluminum 5 g . But they cant take the stress of SS or ti . Ive heard there good to around 7200rpm.

 

Resolute's response is basically on the money, although adjustable cam timing, etc., is primarily necessary to retain good bottom-end on very-high-revving engines.

And some of the particulars he lists are already onboard the Z engine. For reliable higher rpm work, our Aluminum valve spring retainers have to go. (The price on the currently-available Titanium retainers is outrageous. On group buy we should be able to halve that price.) Different springs may be necessary; and, possibly rod bolts - though I doubt it. These engines should be able to turn 7500+ rpm with ease.

 

Thanks for all the replies.









Internal parts from SGP Racing for the VQ35DE

 

Excuse me while I go to the bathroom with these pictures.


Seriously though, the VERY FIRST thing I would do is replace the valvesprings and retainers.

 

Balanced and knife-edged crankshaft along w/ the upgraded valves/springs/retainers/guides. Maybe even use a dual spring setup.

 

F1 cars shouldnt even be mentioned they dont have a normle valve train they use numatics (air comperssion)

and are the things in those pics yours?!!!!!

 

No they dont. They use conventional cam/valve setups. A pneumatic valvetrain would be outrageously slow and prone to failure.

 

Are you sure?

 

For what it's worth, I found this in another discussion forum:

http://www.a-car.com/wwwboard/messages/1713.html

here's the original poster's question:

http://www.a-car.com/wwwboard/messages/357.html


Apparently (according to this guy) F1 cars use springs for opening, but neumatic systems for closing the valves.

 

F1 cars absolutely use pneumatically activated valves.