534 replies to this topic

[mandarinvx]

You just need to put one of the override pulleys on now Joe

Edited by mandarinvx, 06 October 2009 - 07:16 PM.

[alanoo]

I don't understand why you got the low compression pistons fitted ? Harrop in project ? With some higher comp pistons you should have broken the 290+ mark... (note to next SC guys : Diamond racing have some very nice 9.5:1 pistons for the 2.2... forget Wisecos !)

[Crazyfrog (Fab)]

Harrop in project ?

...........knowing joe ..yes

[NickB787]

Harrop in project ?

...........knowing joe ..yes

not till I sort the stand alone.... watch this space!

[rcvaughan]

What did you say Joe? "I'll wait and see what Nick does then copy him!" Me thinking "I'll wait and see what Joe does and copy him!"

[Crazyfrog (Fab)]

What did you say Joe? "I'll wait and see what Nick does then copy him!"

Me thinking "I'll wait and see what Joe does and copy him!"

for nick,joe and rich lol

spend spend spend

[rcvaughan]

No more spending for a while now though! Gives me a while to get used to 260BHP

Edited by rcvaughan, 06 October 2009 - 09:55 PM.

[The Batman]

The reason I got low compression pistons is ecause I want my engine to be safe and not blow up again! Also you can't run a harrop with high compression pistons, so why fit them? like I said they only had an hour to remap it so there is still more to come from my engine. Also you can see that the exhaust is really restrictive now so once I have a 3" system and a remap i hope to see 290 it's like my dual valve springs, I'm not using them to there full potential at 7k revs but it's another safety feature as I don't want to blow it up again!

[The Batman]

You just need to put one of the override pulleys on now Joe

how does that work?

Edit just read about it and do you think this will be a good idea?

Edited by joe_589, 06 October 2009 - 10:34 PM.

[Exmantaa]

I don't understand why you got the low compression pistons fitted ?

Harrop in project ?

With some higher comp pistons you should have broken the 290+ mark...
note to next SC guys : Diamond racing have some very nice 9.5:1 pistons for the 2.2... forget Wisecos !)

Have to say I'm a bit disappointed in your results with these specs, but maybe there's still more in it with some ECU tweaking. But that powercurve is nice and now you at least can use your top HP before you slam in the rev limiter.

Like Alano said, the compression you now run is more suited for higher boostlevels (and our M62 does not like making much boost..)
Wondering of just using stock compression pistons with uprated rods will go well with some cams, as these tend to lower dynamic compression a bit. In the GM build book they raised the standard LSJ 9.5 compression with 10.0 (Diamond) pistons to work well with the GMR cams for 300 HP...

Edited by Exmantaa, 06 October 2009 - 10:44 PM.

[Exmantaa]

You just need to put one of the override pulleys on now Joe

how does that work?

Edit just read about it and do you think this will be a good idea?

Same effect as a smaller SC pulley, only the "belt geometry" is better.
(But you loose the harmonic balancer effect with these.)

[The Batman]

What's a harmonic balance?! Do you think this is a good idea? It says no remap required?

[Exmantaa]

Our heavy crank pulley doubles as a harmonic crank balancer. (Not sure if we have some internal rubber joint there?). For sure some high spec engine guys can tell us more about this.

Edited by Exmantaa, 06 October 2009 - 11:13 PM.

[techieboy]

Will you never learn? Leave it alone. Wouldn't this will be like removing the balancer shafts and not actually give you real "at the wheels" power? If you get one Joe, you might as well see if you can get a 6 peak pulley for the alternator, then you'll be able to run a 6pk belt.

[Exmantaa]

The reason I got low compression pistons is ecause I want my engine to be safe and not blow up again!

it's like my dual valve springs, I'm not using them to there full potential at 7k revs but it's another safety feature as I don't want to blow it up again!

Never knew you had blown your engine before fitting the new shiny internals??

[The Batman]

The piston detonated and that was when it was 270bhp (the red line on the new map) too be honest the durability of the car right now is amazing and I don't want to get to te point where I'm worried about cornering like the high powered turbo boys you will have to give your verdict matt when you drive it that eBay link says there is quite an improvment on wheel horse power but will have to research it more to see if they aretelling the truth

Edited by joe_589, 06 October 2009 - 11:35 PM.

[techieboy]

you will have to give your verdict matt when you drive it

I look forward to it. Seems like a year since I killed the engine at Silverstone and would be nice to have a quick fix.

[alanoo]

The reason I got low compression pistons is ecause I want my engine to be safe and not blow up again!

Also you can't run a harrop with high compression pistons, so why fit them?

like I said they only had an hour to remap it so there is still more to come from my engine. Also you can see that the exhaust is really restrictive now so once I have a 3" system and a remap i hope to see 290

it's like my dual valve springs, I'm not using them to there full potential at 7k revs but it's another safety feature as I don't want to blow it up again!

Well
there's no reason why you can't rune the harrop on high comp pistons, absolutely none. It just needs some mapping

your main restriction on your engine will now be the SC heat (due to the small pulley); maybe you'll have 290 on the dyno with a 3" exhaust but after a few pulls/laps not sure it will be the same...
Higher comp + smaller pulley is always the smarter way to go


About the harmonic damper thing, all of you are right, I'll never fit one of these pulleys for my engine, but for sub 7k rpm engines I think it is safe

(As a side note, I work a bit on a full race M62 build for a friend, and we did some 170°C expansion tests on the 8.9 Wisecos... when I said Wiseco suggested bore to piston clearance is way too small, I was more than right )

[techieboy]

As a side note, I work a bit on a full race M62 build for a friend, and we did some 170°C expansion tests on the 8.9 Wisecos... when I said Wiseco suggested bore to piston clearance is way too small, I was more than right

Okay, do you want to expand on that a little bit? Am just about to take delivery of another set of Wiseco pistons and Eagle rods and will shortly be taking the new cylinder block off for a rebore. I can't afford (mentally or financially) to get it wrong again.

[JG]

that may explain your orignal problem Matt...