427 LS7/T56 in Z4
- Thread starter v8z4
- Start date
not sure if people are joking when they are saying they see 4 cylinder block??? wooowwww....
anyhow op..... awesome project.... lets talk superchargers??? centri or root/screw setup....
id Love to see this with a big vortech YSI bowing into it..... this is one serious project!!!!
any upgraded internals?? what boost are you planning on running??
anyhow op..... awesome project.... lets talk superchargers??? centri or root/screw setup....
id Love to see this with a big vortech YSI bowing into it..... this is one serious project!!!!
any upgraded internals?? what boost are you planning on running??
This will be a centrifugal setup. I'm going with a Procharger D1SC (has a maximum output of 1400CFM and 925HP limit).
While I would have loved to use a Magnuson twin screw supercharger, they stick up too high and I don't want to hack up the hood.
The block is a standard LS6 block (will get a standard 0.005" overbore). The only modification to the block is drilling for piston oil squirts (then head and main studs of course). The heads will be just a good LS6/LS2 ported head with 2.02/1.57 valves (nothing crazy).
The rotating assembly consists of the LS7 forged steel 4140 crank (that can support the factory dry sump system), LS7 Titanium rods, and forged light weight dished pistons.
For boost, I'm trying to avoid going "ridiculous" as the car is already going to be over powered. Have not finalized on the CR yet, though it will be somewhere in the 9s (most likely). Then around 9-12 psi will be more than enough. The supercharger is really "icing on the cake".
While I would have loved to use a Magnuson twin screw supercharger, they stick up too high and I don't want to hack up the hood.
The block is a standard LS6 block (will get a standard 0.005" overbore). The only modification to the block is drilling for piston oil squirts (then head and main studs of course). The heads will be just a good LS6/LS2 ported head with 2.02/1.57 valves (nothing crazy).
The rotating assembly consists of the LS7 forged steel 4140 crank (that can support the factory dry sump system), LS7 Titanium rods, and forged light weight dished pistons.
For boost, I'm trying to avoid going "ridiculous" as the car is already going to be over powered. Have not finalized on the CR yet, though it will be somewhere in the 9s (most likely). Then around 9-12 psi will be more than enough. The supercharger is really "icing on the cake".
tomscott said:Wow this will be a little devil! What about weight? will it be any more front heavy? With a crazy arse
Everything I have found puts the BMW 2.5i/5 speed and the GM LS6/T56 at within +/- 10lbs of each other (one site says BMW engine is lighter, another site says GM engine is lighter). So, I'm calling them the same and not worrying about it.
It will certainly be somewhat heavier as I'm adding a supercharger/intercooler/etc., but people add superchargers to Z4Ms and don't complain about any negatives so I'm not worried there.
It is as it is...
M3 diff is in and ready to be aligned (have an appointment Monday). The diff install itself was direct bolt in (well obviously since BMW designed it to be interchangeable with the E46 rear).
I opted to machine the M3 diff cover rather than buy a new Z4M diff cover ($250 + shipping from Germany and 2 weeks wait). I just marked (actually sprayed bluing over the rear cross bars) where the bars would hit, mounted the diff cover in the mill, and removed fins as necessary. End result gives plenty of clearance while retaining more cooling capacity than the Z4M cover (not to mention I'm $250+ shipping ahead).
While I was swapping, I also converted from "BMW specific" steel braided brake lines to standard steel braided lines with -3AN fittings and lengthened by a few inches. This way I'm prepped to convert to Porsche calipers in the future.
I also scored a set of Eibach Pro-Kit springs a local guy was dumping ($50). He had purchased them new, never installed them, and traded his Z4 for a new 5 series. So being stuck with a set of "worthless" springs, he just wanted them gone.
The hardest part was getting the stock 5 speed drive shaft shortened. Not surprisingly, the drive shaft tube it's a metric pipe (so standard 1310 yoke ends won't fit it) and nobody around Phoenix has the flanges necessary to grab a BMW year diff yoke. I had to machine an adapter sleeve to convert the metric pipe ID to an American 1310 drive shaft yoke. Then I had to machine a hub for the drive shaft shop to be able to grab the rear flange.
In the end, it took a week of head scratching/trying different options, a half a day of machining parts, and 30 mins. for them to actually shorten/weld/balance the shaft.
So, some pictures:
Most places they just swipe your rims/tires, around here they take the whole rear axle.
All in, ready to go.
Modified M3 Diff Cover:
I opted to machine the M3 diff cover rather than buy a new Z4M diff cover ($250 + shipping from Germany and 2 weeks wait). I just marked (actually sprayed bluing over the rear cross bars) where the bars would hit, mounted the diff cover in the mill, and removed fins as necessary. End result gives plenty of clearance while retaining more cooling capacity than the Z4M cover (not to mention I'm $250+ shipping ahead).
While I was swapping, I also converted from "BMW specific" steel braided brake lines to standard steel braided lines with -3AN fittings and lengthened by a few inches. This way I'm prepped to convert to Porsche calipers in the future.
I also scored a set of Eibach Pro-Kit springs a local guy was dumping ($50). He had purchased them new, never installed them, and traded his Z4 for a new 5 series. So being stuck with a set of "worthless" springs, he just wanted them gone.
The hardest part was getting the stock 5 speed drive shaft shortened. Not surprisingly, the drive shaft tube it's a metric pipe (so standard 1310 yoke ends won't fit it) and nobody around Phoenix has the flanges necessary to grab a BMW year diff yoke. I had to machine an adapter sleeve to convert the metric pipe ID to an American 1310 drive shaft yoke. Then I had to machine a hub for the drive shaft shop to be able to grab the rear flange.
In the end, it took a week of head scratching/trying different options, a half a day of machining parts, and 30 mins. for them to actually shorten/weld/balance the shaft.
So, some pictures:
Most places they just swipe your rims/tires, around here they take the whole rear axle.
All in, ready to go.
Modified M3 Diff Cover:
pokeybritches
Member
Very interested in the diff swap. I'm looking at LSD options now, and haven't really compared the different part numbers between the Z4M and 6 speed Z4.
What are you doing about the rear brakes? With Z4M or M3 rear brakes only, the bias will be way off.
What are you doing about the rear brakes? With Z4M or M3 rear brakes only, the bias will be way off.
bigdog said:
Yup, 383 is somewhere between 6.2 and 6.3 liters. :evil:
Here's the writeup I just did about the results. If you have a 6 speed Z4, PM me. I have a drive shaft from a Z4M sitting in my garage that should make this swap literally a direct swap.pokeybritches said:
http://www.z4-forum.com/forum/viewtopic.php?f=2&t=51444
In order to use the M3/Z4M rear trailing arms, you have no choice but to use the M3/Z4M rear brakes. For some stupid reason, the Z4 and M3/Z4M rear wheel hubs are different lengths. As a result, the Z4 and M3/Z4M rotor hat (where the e-brake resides) are considerably different dimensions.
Right now I only have the M3 rear brakes (stock Z4 front brakes). While the bias is probably somewhat off, I always felt the rear end's braking capacity was under utilized (never could get the rears even close to locking). So in some aspects (to me) it feels like the added braking from the rear end has been beneficial. Long term I plan to convert to Porsche 996 calipers front/rear, using the CSL front rotors and current M3 rear rotors.
1066 Country
That V8Z4 is epic i so wish you where in the UK i would love to have made bits n bobs for this. Keep the write ups coming 
M3 rear end is something i have been thinking about. And is now firmly on my to do list. I was thinking of supercharging my zed with a twin screw instead of a centrifugal type. But now i am going to go look and see what V8 or V12s i can get my hands on!!!
I doff my cap to you good sir bloody well done.
M3 rear end is something i have been thinking about. And is now firmly on my to do list. I was thinking of supercharging my zed with a twin screw instead of a centrifugal type. But now i am going to go look and see what V8 or V12s i can get my hands on!!!I doff my cap to you good sir bloody well done.
Bing said:can't wait to see it fitted
I want to know what it'll sound like, probably like God snoring
Being basically nosy I just googled fountain hills. You have somewhere called apache junction just down the road! Crazy. It looks like a great place to own a sportscar. Luck with the build.