Going Turbo.. High Mileage

[V1990]

Going turbo soon on my M30B35. Question of concern regarding the 253k (and climbing) on my odo. I've heard of some going turbo at 200k, but never more than that. Only looking to boost max 12psi. I've considered a full rebuild but would like to keep costs down. Rebuilt head, ARP studs, and MLS headgasket.. Slap that slug on?

Bottom end is solid: compression is good, no burning of oil. But I would like to get some feedback on boosting a highmileage daily driver.

Thanks in advance!

[Hofmeister]

I'm buying parts to boost my 278k m50. It's not the miles but how the miles were done and maintenance.

[V1990]

Third owner; oil changed every 2500mi mostly highway commuter miles. Past two owners were dealer maintained. So swap the head and boost boost?

[Layne]

I wouldn't bother with the head rebuild right away. If you blow the gasket, then worry about it.

[V1990]

Really?

[Leonator134]

Good luck Vic, should be sweet. Boost the hell out of it!

[doubleJC]

We shall be turbo twins soon..

[Hofmeister]

Really?

You can, I like preventative work though. My plan was to do low boost on stock gasket but working at a junkyard I can get a head cheap enough to get it done up on the side. Then just instead of days of downtime when machinig it id already have it done for MLS gasket.

[V1990]

Thanks guys! So if I run mild boost (8-12psi) I'd be able to squeeze a possible 30k out of my stock HG and such?

This way I may enjoy boost as I prep my rebuilt head/block.

[imae30driver]

30k???? Maybe.. Id guess 10k @ 12 psi... (My guess)

[mboor]

Thanks guys! So if I run mild boost (8-12psi) I'd be able to squeeze a possible 30k out of my stock HG and such?

This way I may enjoy boost as I prep my rebuilt head/block.

It all depends on how heavy your right foot is.

[Leonator134]

Boost this one for now.. but after it's running and driving pick up another M30 to build and eventually swap in.

[Ionz]

You can look in to how much a cut-ring gasket will run you.
I know you can get a cut ring gasket with ARP studs and a copper spacer (to drop compression to 9.5:1) on a s52 for like $7xx.xx, good for ~30psi. MLS gaskets are finicky and not the most reliable things in the world.
Personally, since I have another car, I'm going to build my motor on the side so I'll be able to slap it in, and go to the dyno. But if you are planning on a DD turbo M30, and are running >10psi I think your motor will be fine until you build one.
Have you done a Leakdown test? Compression testing a motor only tells you so much. What it doesn't do, is tell you if the rings are bad or if you have a pre-existing headgasket failure that isn't affecting your compression numbers yet. IMO, you should have that done first (most performance shops can do it for you for relatively cheap) then if results come back positive, slap that turbo on; if not, build a motor.

[JesterMX6]

sounds like the motor has just finished the break in period. go for it.

[V1990]

Good luck Vic, should be sweet. Boost the hell out of it!


We shall be turbo twins soon..

May make a build thread.. maybe not. We'll see when the time comes.


You can, I like preventative work though. My plan was to do low boost on stock gasket but working at a junkyard I can get a head cheap enough to get it done up on the side. Then just instead of days of downtime when machinig it id already have it done for MLS gasket.

How much does that run you? If you can have a head done up for me I'd be interested to buy.


You can look in to how much a cut-ring gasket will run you.
I know you can get a cut ring gasket with ARP studs and a copper spacer (to drop compression to 9.5:1) on a s52 for like $7xx.xx, good for ~30psi. MLS gaskets are finicky and not the most reliable things in the world.
Personally, since I have another car, I'm going to build my motor on the side so I'll be able to slap it in, and go to the dyno. But if you are planning on a DD turbo M30, and are running >10psi I think your motor will be fine until you build one.
Have you done a Leakdown test? Compression testing a motor only tells you so much. What it doesn't do, is tell you if the rings are bad or if you have a pre-existing headgasket failure that isn't affecting your compression numbers yet. IMO, you should have that done first (most performance shops can do it for you for relatively cheap) then if results come back positive, slap that turbo on; if not, build a motor.

Great advice! I'll look into it.. I've only heard of running an MLS headgasket but never a cut ring. I'll have a leakdown test done before I make any big decisions.


sounds like the motor has just finished the break in period. go for it.

Amen!


Thanks guys for all the helpful feedback. I really appreciate it as I am now treading through unknown waters (to me anyway).