group order cp forged pistons!

[fr335tyl3r]

Ralliart...the cam change has been proven necessary by several people on this forum to ensure that we can bust through the 200hpatw barrier. Basically everyone else that has used the standard cam will run into a power dip on the dyno high in the rev range with the standard cam which is corrected with the installation of a new cam.

This is my quick and dirty knowledge of it, someone like cookie would be able to fill in better.

[logik]

Are you talking about using the Sigma Astron motor Cam in the Sirius 4G63 ??? No go bro , different engine . If you just mean the same grind on a 4G63 cam , again being very different engines it may , but won't necessarily , work .

dude dont be stupid

The standard Starion cams are actually very large and are already capable of 7500rpm .

no they dont

[Mr Ralliart]

I don't want to get into an argument about this but why do I have to be called stupid? You asked a question , I gave a possible answer .

The reason I said the cams are capable of 7500rpm is because I've seen them do it on several engines , they certainly have the duration . I didn't say they were still pulling hard or anything like that , THEY WEREN'T. I just said they can rev that high .

And as for needing a bigger cam to break only 200 rwhp ???!??....

I think these guys need to SERIOUSLY consider changing their Engine builders .
.

[fr335tyl3r]

Mate AFAIK, we aren't talking about a rebuilt engine here. We are talking about MPI and turbo change. Standard internals, etc will cap out at about 170-180rwhp from memory.

[Mr Ralliart]

Pardon my ignorance , I don't know what AFAIK means .

And I wasn't talking about engines with MPI and Turbo changes .

And as for standard internals capping out at 170-180 rwhp ,

you guys DEFINATELY NEED TO CHANGE YOUR ENGINE BUILDERS or TUNERS.
I've gotten 170rwp at just over 4000 rpm with an engine that had only a Fuel cut defender , 2.5" exhaust , Garrett T3 bought from a swapmeet on steampipe manifold ,12psi boost , re-graphed dizzy ,portmatched head, cold air induction , and an UNbalanced bottom end with standard pistons .

[fr335tyl3r]

AFAIK - as far as i know

i'll find the dyno graphs showing the power dips that people were experiencing.

[logik]

The reason I said the cams are capable of 7500rpm is because I've seen them do it on several engines , they certainly have the duration . I didn't say they were still pulling hard or anything like that , THEY WEREN'T. I just said they can rev that high.

dude you could probably rev a lawnmower engine out to 50,000rpm but it aint making any power

and you did NOT make 170rwhp at 4000rpm, that'd be utterly impossible. if you can post a dyno sheet i will eat my words

[mrb1]

And as for needing a bigger cam to break only 200 rwhp ???!??....

There is no way you can make over 200-210rwhp with the stock cam/head and stock CR. I have measured the airflow and it just stays flat as soon as it reaches that point.
I have seen many dyno sheets that confirm this including lots of my own.

As for reving to 7500 RPM I would agree this is possible for sure with a suitable cam and valve springs however the stock pistons would be a bit vunerable.

I will be fitting a Camtech cam shortly to a stock engine and will post the before and after dyno sheets. I am getting a mid spec cam you could certainly go bigger than the one I have choosen. It won't be a 7500 RPM grind.

[coop1er]

If you use enough boost pressure, with the right turbo, then surely
200hp atw is possible with the standard cam/head?

I would probably be interested in some of these pistons in a .020"
oversize. But I would prefer them in a standard sohc format rather
than dohc pistons. Are these pistons customized fom blanks or just
off the shelf dohc units?

[mrb1]

If you use enough boost pressure, with the right turbo, then surely
200hp atw is possible with the standard cam/head?

That's what I just said. But not OVER 200-210rwhp. My car makes 200rwhp with stock cam/head.

[coop1er]

Ok I didnt read your post correctly. I still think it is possible to
achieve over this 210hp atw hurdle. Maybe nobody has done it yet, but
this doesnt mean it cannot be done.

What turbo are you using to get 200hp atw? If I was trying to get more
than 210hp atw, I would use an exhaust housing bigger than a Mitsubishi
080, and hopefully with enough boost pressure, the flow would make the
power required.

[sucka]

interesting thread. there are a lot of points of view on this subject of cams.
funny how this started as a for sale post about pistons...

[mrb1]

Ok I didnt read your post correctly. I still think it is possible to
achieve over this 210hp atw hurdle. Maybe nobody has done it yet, but
this doesnt mean it cannot be done.

What turbo are you using to get 200hp atw? If I was trying to get more
than 210hp atw, I would use an exhaust housing bigger than a Mitsubishi
080, and hopefully with enough boost pressure, the flow would make the
power required.

The 080 housing is not the problem the stock cam is

[coop1er]

But surely if you reduce the pressure in the exhaust manifold (which would
typically be higher than the boost pressure you are using), then airflow
through the engine must increase @ the same boost pressure.

[toysrus]

But surely if you reduce the pressure in the exhaust manifold (which would
typically be higher than the boost pressure you are using), then airflow
through the engine must increase @ the same boost pressure.

Correct, steam-pipe or Split-pulse