Hello I've searched and searched through this forum for an answer of using higher compression pistons with the m45 roots supercharger for the 2.4 engine.
My thoughts where would running 10.5 compression pistons be okay along with water injection, on the 2.5 pulley? And if so what bore should the pistons be .040, .020, stock?? Also what thickness should the head gasket be? Thanks for the answers in advance hopefully someone will come along.
I would have no problem running that kind of compression on the M45.
FU Tuning
At what bore would you recommend I run for the pistons at that compression and what gasket thickness?? Correct me if I am wrong but with a thicker gasket does compression go up in the final ratio??
A thicker gasket will actually lower your compression ratio... a lot depends on whether you deck the head/block at all and make up for it with gasket thickness.
No real sense massively overboring an LD9 to be honest... 0.020 is just fine and leaves space in case anything happens and you potentially need to re-do the block again.
10.5:1 should be pretty fine with the M45 if that's your goal... your success will be in the tuning and any mods you can do to cool the intake charge to help you. In my opinion a higher CR is a good offset for power rather than putting on a smaller pulley and spinning the charger faster... but we all approach engines differently.
-Chris-
-Sweetness-
-Turbocharged-
Slowly but surely may some day win this race...
My goal is to keep the m45 on the engine with the safest/streetable compression ratio to accompany the charger.. if I can get 250 at the wheels with the blower off of water cooling and high CR that would be great..
I would love to see 250 at the wheels. Whats the highest dyno for an m45 anyway?
I'm working on pretty much this build right now.
10.5 stock bore , m45 2.6" pulley, OD pulley. I hope to have a build thread started around march.
I'll be running meth when i get some cash for a kit. Although I'm not that worried about pre-det, its really not that high of a CR and your not pushing that much boost, it'll still help keep the charger cool.
Hope some of that helps.
Quote:
Whats the highest dyno for an m45 anyway?
I think I saw in a thread someone said they where at 230, but there was nothing to prove it.
-Z Yaaaa- wrote:bore the block .080 and do 12:1.
Are there any advantages into over boring the block on the 2.4? Wouldn't the CR of 12.1 be overkill with .080 bore along with the m45,or is that really the only option I have to yield 250whp with charger?
250whp on a built and properly tuned LD9 w M45 is very doable.
I have made 219whp on a stock 134k LD9. Plan to hit the dyno in the very near future to update the numbers since some changes.
I would not overbore unless you have to. Go with a flat top piston. Try and get the compression around 10:1-11:1 and get a very good tune with a 2.5 charger pulley, and a overdriven crank pulley, and some meth/water injection mix. Good flowing 2:5 exhaust, with a header. 250whp should be easy, if tuned properly.
FU Tuning
Ok Ill try again. Anyone know what the highest dyno numbers are so far for a m45 setup?
Craig wrote:Ok Ill try again. Anyone know what the highest dyno numbers are so far for a m45 setup?
I remember hearing some years back about someone making around 232whp, but I think that was with spray as well.
I know another member made 217whp on a built LD9 and a M45.
I have made 219whp.
FU Tuning
SweetnessGT wrote:In my opinion a higher CR is a good offset for power rather than putting on a smaller pulley and spinning the charger faster... but we all approach engines differently.
-Chris-
Thats my thought process too. Especially when youre using a supercharger where the faster you spin the less gain you see due to heat and the limited compressability (is that a word) of any gas. You get that with a turbo too but the extra effort to compress the air isnt taken from the rotation of the engine. The Law of Dimishing Returns is a harsh mistress.
I wonder if Publikdisturbance got his setup done. He was doing something with a higher than normal CR and an M45. I just dont remember what exactly.
Addicted to meth wrote:Craig wrote:Ok Ill try again. Anyone know what the highest dyno numbers are so far for a m45 setup?
I remember hearing some years back about someone making around 232whp, but I think that was with spray as well.
I know another member made 217whp on a built LD9 and a M45.
I have made 219whp.
hmmmm. I was just browsing youtube and found this guy. Read comments. 10.1 compression ratio, cams, blah blah and a 2.4 pulley? Making 226 max to the wheels.
http://www.youtube.com/watch?v=lVN2FtqRPZo&feature=youtube_gdata_player
My charger was on another loca Z24 before I got it. I also tuned it (street tuned). It has stock cams, same header I have with the 2.5 charger pulley, and stock crank pulley. No meth. IAT's were 190's and guy only made 187whp.
Put it on my car with meth, and cams, and 57mm TB made 208whp. Then later the OD crank pulley, more meth and more tuning 219whp.
My point I do not see that guy making 226 without meth on a 2.4 pulley.
FU Tuning
I bet that car was a blast to dive on the street..
-Z Yaaaa- wrote:karo made 259whp without a blower...
just saying. 
i bet with a blower and a proper tune it would have made more.
just saying.
FU Tuning
Is anyone with an m45 running a racetronix fuel pump?
Addicted to meth wrote:-Z Yaaaa- wrote:karo made 259whp without a blower...
just saying.
i bet with a blower and a proper tune it would have made more.
just saying.
it had a blower for a while but not a tune....i bet it was faster without the blower as it sat while i knew it.
