Hey i'm not bitchin out on nothing damn it!! I'll get around to the z32 rear brakes eventually... just have to topple this project first!
JDMking: i'm using Mckinney mount kit
OpeLok: thanks for the compliments! After the install that is the very next step... I've gotta find a tuner!! No i don't have a new head gasket... I discussed with jonpowell that the 555cc injectors are good to about 360hp at 80% (safely not maximum) and the stock head gasket will most definately hold that kind of power... but if it happens to pop... just shut it down immediately and replace.
HKS states that this turbo will produce 400ps at 88.3kpa which all converts to 394HP at 12.8psi ... I will probably have it set at 12psi all day long but we'll see when it's finally tuned.
Nismo241: thanx for the insight... it's always good to learn new things about the PFC.. but I'm definately not gonna be the one tuning it
mrbojangles: According to sydneykid of skylinesaustralia.com the cylinders in the greddy manifold do happen to lean out... he's tested this on several of his track cars... here's a post from
http://www.skylinesaustralia.com/forums/showthread.php?t=32556&highlight=greddy+intake....
SydneyKid:
"Sorry B-Man, but looking inside the Greddy plenum is not what I would call "just magic". It is full of casting dags and tooling join marks, there is not one tiny bit of hand finishing on the inside. Sure the outside looks pretty, but I don't think the engine cares 2 hoots about what it looks like. Personal experience has been that they don't flow very well and they have poor distribution. The rear cylinders (particularly number 6) suffer from pressure wave build up and get more airflow than the front cylinders. This results in leanness of the rear cylinders which can easily be seen on the dyno with primary exhaust manifold temperatures and lambda readings.
I have never ever seen this with the standard inlet manifold. Testing under vacuum on a flow bench that shows a difference of 41% (240 / 340) is simply not the same in the real world under boost. If that was realy the case Nissan would have 370cc injectors in #1, #2, #5 & #6 and 525 cc injectors in #3 & #4. Now we all know that is simply not done.
Sure upgrading plenums has a place, my rule of thumb is on an engine at the limit of the standard internals (ie; over 450 bhp). But until you start doing internal work on an RB25 then there is nothing to be gained from spending your money on changing the plenum. Just recently I have seen a couple of cars out of Japan with over 500 hp that still have the standard plenum on them, Zeni Tani for example are strong advocates for keeping the standard plenum on RB25's up to 550 hp.
Don't get me wrong, I am not saying you should never upgrade the plenum. What I am saying is there are better ways to spend your money. Sure if I had done everything else on an RB25DET and still had some money left then I would do the plenum. But it would be very low on my priorities.
Actually it wouldn't even make it onto my priorities, if I had that much money to spend. I would put an RB26 head and inlet system on it and benefit from the multiple throttle bodies, non hydraulic followers, no VVT, wider variety of camshafts, larger head studs, etc."
Also...
"Lastly the comment "I have no-doubt that you are seeing 500HP cars with standard plemum - I would think though they are seeing more air flow to 3 & 4 than 1 & 2."
I have tested this theory on a 295 rwkw RB25DET on the dyno with the standard plenum. I have a laser guided pyrometer with which I can very accurately record the temperatures of the exhaust manifold primaries. There is no discernable difference in temperature between 3 & 4 and the rest. Consequently there is no discernable difference in airflow because I have used a set of matched injectors. If there was an airflow difference then I would be seeing increased individual EGT temperatures as a result of the leanness.
I have also used individual lambda sensors (we have 4 Motec F&W's) on another car (it had fittings welded into the primary pipes). This car had a Greddy plenum and it showed leanness in A/F ratios in #6 (and #5 to a lesser extent). This was despite having the slightly higher flowing injectors in those cylinders. To fix this I had to adjust the individual injector duration on the ECU, around 3% on top of the already higher flowing injectors (2% and 1% respectively).
Now this is not much (5%) but if you don't correct for it you end up with a couple of lean cylinders or you end up with 4 rich cylinders. So it's either detonation or power loss, take your choice."
:eek4: :1bowdown :25drool
