M50 Stoker Turbo

[///MLIFE]

So I'm picking up a complete M50TUB25 swap as well as and a M52B28 bottom end this weekend. I'm thinking of either options:

1.M50 Head just bolted on the M52 bottom end. Thus having a OBD1 M52 essentially. What kind of CR would I be looking at and what thickness HG would I use? I've heard of people doing this for stroker NA builds and being ~11:1 but I'm not 100% sure.

2. M50 Head and M50 block w/ M52 crank/rods/pistons installed. Making this a M50 stroker of sorts. I was also told the side walls of the M50 were thicker than the M52 but I thought they were essentially the same block?

Then, the plan would be:
ARP Head Studs and Rod Bolts
.140 MLS (Or whatever would work to lower CR)
60 lbs Siemen Deka Injectors
Walboro 255
Megasquirt or a ROM tune

For turbo selection, I was thinking may an HX35 (cheap route) or possibly a GT3076/3582/Precision6262 or some equivalent BB turbo with a decent spool. I'd love to hear what everyone else runs and if possibly dyno sheets to compare spool of different turbos and setups.

Looking at other threads on an HX35 at 18psi I should be able to put down about 400 with a proper tune. I've seen people "reliably" run up to 21psi and be somewhere around 450 or more (before you bend a rod at 500)

The plan is run this (and pray it doesn't blow up) until I'm out of school and can actually put pistons/rods in the motor and no cheap out. Thanks for the input R3V; I'm excited to soon join the 24V Turbo crew :D

[GunMetalGrey]

What did you have in mind for a budget?

11:1 compression would be no good for boost, I would honestly skip the m52 bottom end unless you are getting it very cheap, you wont be able to get a whole lot more out of it and then you have to worry about franken motor problems.
Other than that thought your simple plan looks good.

I run an m50nv on ms3x with an hx35, I feel like it spools very quickly but I have not had any other turbo on the car to compare!

[///MLIFE]

I'm thinking i'll pass on all the M52 stuff. This M50 has 40k on the rebuild so no need to rip the whole engine apart.

I'm thinking around 2-3k should have it tuned and driving around. I'd like to just do a chip because I'm running a stock motor and wouldn't use all the functions of a MS but I know the tune is always the most important part of the build

Also,how much power is the stock clutch good for? I plan to replace it before I put the motor in, but I'm just curious. Whats your setup? (Injector,Manfiold etc.)

[GunMetalGrey]

2-3K is pretty low, but not impossible depending on what you already have.
40k miles on the rebuild is nice, easy enough to just slap in a headgasket and headstuds (~$450 of your budget gone)
I am not sure how much the stock clutch will get you for power, but I know it isn't a whole lot when you start throwing boost at it, especially if you are running over 7psi.

I run:
ARP and MLS .14"
80lb Deka Injectors
Blunttech Top Mount Manifold
AASCO 240mm flywheel
Spec Stage 2+ clutch
Tial MVR 44mm wastegate
MS3x
HX35
Walbro 255
Full 3" 304 exhaust

Excluding exhaust that list is a bit over $3,700 new, which is why your budget may be tricky.

[Northern]

1.M50 Head just bolted on the M52 bottom end. Thus having a OBD1 M52 essentially. What kind of CR would I be looking at and what thickness HG would I use? I've heard of people doing this for stroker NA builds and being ~11:1 but I'm not 100% sure.

2. M50 Head and M50 block w/ M52 crank/rods/pistons installed. Making this a M50 stroker of sorts. I was also told the side walls of the M50 were thicker than the M52 but I thought they were essentially the same block?

Then, the plan would be:
ARP Head Studs and Rod Bolts
.140 MLS (Or whatever would work to lower CR)
60 lbs Siemen Deka Injectors
Walboro 255
Megasquirt or a ROM tune

For turbo selection, I was thinking may an HX35 (cheap route) or possibly a GT3076/3582/Precision6262 or some equivalent BB turbo with a decent spool. I'd love to hear what everyone else runs and if possibly dyno sheets to compare spool of different turbos and setups.

Looking at other threads on an HX35 at 18psi I should be able to put down about 400 with a proper tune. I've seen people "reliably" run up to 21psi and be somewhere around 450 or more (before you bend a rod at 500)

The plan is run this (and pray it doesn't blow up) until I'm out of school and can actually put pistons/rods in the motor and no cheap out. Thanks for the input R3V; I'm excited to soon join the 24V Turbo crew :D

Swapping one head for another should have no effect on CR. Should remain 10.5:1 for M50tu or 10.2:1 for M52b28 bottom ends.

If you want to stay under 9-10psi, you could manage with the stock headgasket, otherwise .140MLS(or equivalent) or low comp pistons will help you go past that.

I have never heard of a significant difference between M50/M52 Iron blocks, other than the OBD2 crank boss at the back for OBD2 blocks.

Depending on your goals (and as GunMetalGrey said) I would consider the Deka 80lb if you think you may ever run E85, or if you will ever outgrow the 60's. It's cheaper to do it now than buy twice.

If you are staying OBD1, a standalone (such as MS) would be good to have(esp. if you want boost by gear, antilag, etc.) If you can get an OBD2 setup, there are lots of people who tune the MS41 DMEs with excellent results (ex. RKtunes)

Turbo choice is up to you and depends heavily on budget and power goal.

With M52 bottom end, the lowest I've seen cars bend rods is high 500's, but it could definitely happen much lower with a bad tune. I've also seen cars reach high 600's without bending rods.

Personally would recommend the M52 bottom end over the M50 setup because:
1: Displacement
2: Forged crank

If you can get some OBD2 electronics and DME with it, all the better.

Also, for clutches on a budget, I would look at the F1 Racing/FX Racing Stage 3 clutch/flywheel setups (BF.C classifieds have a few used for sale for dirt cheap, and they're cheap new) or look into setups using the M30 single mass flywheels with the Sachs 765 Pressure plate.

[///MLIFE]

I thought the budget was a little to conservative. My E30s running and driving fine now so the plan was to basically build it on the stand then put everything in together. Turns out the engine I was looking at wasn't good :( so i'm still on the hunt for a swap.

[///MLIFE]

Okay, Picked up an M50 Vanos w/ Harness and ECU. Also just bought a GT3582 for a steal; how do you think the spool will be? (This is a BB one just to be clear)