need advice, ive run 13 to 1 pon 98 before and thast been ok, has anyone done 14 to 1? Wanna lift it to the maximum possible!
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need advice, ive run 13 to 1 pon 98 before and thast been ok, has anyone done 14 to 1? Wanna lift it to the maximum possible!
Yes I was using that much comp in our Hyundia super tourer when we where racing it, it took us a very long time on the dyno tuning it and we wasted 3 race meetings with blown head gaskets but once ACL made us some special head gaskets the engine was perfect and we raced it like that for 14 meetings and it is still sweet as.The only fuel that I found to handle that much comp was Mobil's 8000 Premium with all the others you could not use enough ignition advance to make power.
Regards Dyno Dave
DynoDave, what sort of porting flow did the head have? the head that we want to use is flowing a little too much, and we are thinking of using restrictor plates to increase lower rpm torque.
The cams are going to make poewr to 13k rpms, so they claim. We need a high enough CR to maintain power, or else the falling VE from the high rpm will see us platue or lose power. Thats why we want high as possible. Any higher than 14:1 possible?
This is on a b18c type R motor, NA.
omg... b18c revving to 13k? what type of cams? titanium spec z?
wanna run? ;)
Screw the cams, what about the valves and valve springs???Quote:
Originally Posted by mugsee
With the inertia loading at 13,000rpm, the valve collets will be the next Mars explorer...
That is too many Revs for me 10,000-10,500rpm are the most I have ever had to use in a Honda engine or would like to.
Regards Dyno Dave
Thanks captian obvious aka McChook. Ill just go and do everything else except valves and valve springs. :P
Dynodave, its what the manufacturer claims but if i gave u the specs, Id find them hard to believe that even at 13k the power doesnt fall off. At this stage the flow bench is being used to port the head, and custom extractors are being match ported to fit too.
Mugsee: Everything has been taken apart for this rebuilt motor, but we are struggling with piston specs. We are thinking 14:1 right now, but we mgiht even try pushing 15:1 in connjunction with running octane booster to the 98. up to the owner if he does this or not.
Its being bored out to 2 litres (a little bit under), the quad throttles are being abit of a pain, but restrictor plates are being used, not sure how thats going to work, im not the builder so i dont know. As for what it will actually rev, its more likely to rev only to 12k rpms if u take into account all other factors in the head.
peace.
That sounds like one beast of an engine! make sure you tell us how it turns out!
I think you took that the wrong wayQuote:
Originally Posted by pornstar
I wanna know what you're using in the head - We're with DynoDave, we keep it under 10,000rpm (200fwhp BTW).
I wanna know what you got in there - springs and valves, what the hell you gonna use - because I don't know of any that will take that sort of punishment
OK sorry if i sounded like Im giving it to ya, i was just kidding hence the " :P " sign.
For a normal street car 10k rpms would really be good enough, but this motor is being built to take on PI and other circuits where the straights have been troubling past engines. previously, the long straight on PI had been creating problems for the owners previous motor and box because he would have to change to 5th gear just near the end of the straight, hence drop rpms, but jsut before he enters the first turn, this is not opitmum. Therefore to rectify the problem, the car owner wants the revs to go to 13k rpms, and hence keep him in the top of 4th without having to do 2 gear changes, this is one of the main reasons why he wants to be able to rev to 13k rpms.
He might not actually make power up past 11.5k rpms, but at worse he will keep the power platued there and thus not lose any power, and only maintain rpms so he doesnt have to change.
As for what is being used. Its actually all being custom built right here in exotic melbourne, dont ask me anymore on who it is as i cant name him right now. The valves and springs are titanium items, and they are being custom made for this setup, but depending on how a group buy response goes, it may be made to a limited number ie 20 sets.
Ill pass on the interest to the owner of the car, and leave it to him to answer any more info he he pleases. Otherwise if there are more general things that i cna answer go ahead and ask, ill do my best to answer. For those more mechanically inclined, the builder has hinted at the need to remove rocker arm designs, and go to bucket and shims. its not definate, at this stage this is all being worked out, but there are some aprts already being used as testing trials on the car. And for those who hve even more mechanical knowledge, then u will also realise which the car has to run a bonnt scoop/vent.
Again, without giving it to you - wouldn't a close ratio gearbox or a change in the final drive be a safer, easier and cheaper solution. 13K revs will destory the engine in no time, and the valves and springs, being titanium, will have to be replaced often. Rebuilds will be frequent and expensive. Unless your running a BTCC Super Tourer, this sort of extreme work is unjustified IMO
We run our engines at PI, and sure, we lack the HP numbers in a straight line, but not much else in the class can keep up with the same displacement...
I guess it is a race car, so what class is the car running in??
What lap times was this car doing around PI as we have raced down there and I would be keen to find out what times this car has done.
Regards Dyno Dave