Suggested M20 engine rebuilders / shops

[CZero]

So, it's 2025 and I'm sure the M20 isn't quite as popular as it used to be, with everyone seemingly using the M50 as a baseline at a minimum. Are there still some reputable m20 engine rebuilders or shops people use? Can anyone point me in the direction of a reputable company?

Background details: I bought a car in the last few months with a turbo'ed m20 that was fully built and I'd like to make some changes and speak with someone that really knows these motors. Engine is spitting coolant out of the crankcase breather once up to operating temp and I'd like to find out why along with redoing the head and turbo setup once fixed.

[McGyver]

There are plenty of people building and working on m20s. In fact, probably more people building m20s these days than 10 years ago when everyone was swapping in m5x engines.

We would need to know where you live to suggest a shop.

[CZero]

There are plenty of people building and working on m20s. In fact, probably more people building m20s these days than 10 years ago when everyone was swapping in m5x engines.

We would need to know where you live to suggest a shop.

Sorry about that, I really thought I had included where I was! I am in Houston, TX.

[stoph]

Or any shop within an hour or so of Charlotte, NC ;)

[Nohawkscott]

I’m wondering about suggestions in Texas too. I’m thinking about getting a short block rebuilt

[TXM20]

X3 Texas. Houston to be exact.

[DesertBMW]

Background details: I bought a car in the last few months with a turbo'ed m20 that was fully built and I'd like to make some changes and speak with someone that really knows these motors. Engine is spitting coolant out of the crankcase breather once up to operating temp and I'd like to find out why along with redoing the head and turbo setup once fixed.

Most good shops won't even want to do anything with some blown up turbo M20 engine. Cheaper to find another good M20 engine.

[CZero]

This really isn't just "some blown up turbo M20 engine,"haha! It's fully built from the top to bottom. It's just a head gasket that blew... nothing serious. Replacing this motor would be ~15k based on the first build pricing, so I'm not looking to replace it with another stock engine.
I just want to swap to E85, resize turbo, and retune it. I'd just prefer to pay someone who has experience instead of trial and error on an expensive setup.

[DesertBMW]

it can be something more than just a head gasket that failed. Most good mechanics don't like to work on custom engines, they like to work on how the engine is original and stock.

[McGyver]

I've found that most engine builders would rather work on something interesting vs a stock rebuild. I've found that most shops don't want to touch a ratty build, but are more than happy to work on a quality build with quality parts.

[82eye]

I've found that most engine builders would rather work on something interesting vs a stock rebuild. I've found that most shops don't want to touch a ratty build, but are more than happy to work on a quality build with quality parts.

he needs a specialty shop. there isn't an indie euro shop here that would come within a thousand miles of touching that. there are specialty speed shops though that would take it on if the original build was deemed worthy.

it's incredibly spendy though.

[CZero]

I've found that most engine builders would rather work on something interesting vs a stock rebuild. I've found that most shops don't want to touch a ratty build, but are more than happy to work on a quality build with quality parts.

For anyone wondering, I ended up taking the car to ABR here in Houston. I've used them for a number of my bmw cars and they seem to know what they're doing. This build definitely had a lot of attention to it from the previous owner which is one of the reasons I was willing to buy it. Because of this they didn't mind working on it. The car itself is very clean overall inside and out,

Now onto the findings, after seeing the blown head gasket we went ahead and disassembled the head and pressure tested it. By removing the cam and doing this, we discovered a 12" long crack in the head that was just bubbling as soon as pressure was applied. Yikes. So, we ordered a new head and are going to elect to NOT weld the coolant channels. The block is already o rings and we will use an MLS head gasket instead this time. It does have ARP headstuds already also.

Full build list is below:
megasquirt2 pro pnp standalone (I plan to get the ethanol sensor for e85 tuning)
8.5:1 CR Carillo forged pistons
Eagle H-beam forged conrods
o-ringed block with stainless steel wire
VAC motorsports high performance main bearings
vac motorsports coated con rod bearings
dual valve spring kit
forged rocker arm set
280/274 cam
meth injection
775 fic injectors (I plan to upgrade to 1050x for e85)
aeromotive 340 stealth drop in fuel pump (plan to upgrade to a larger walbro for e85)
precision 5831 turbo
snow meth injection kit and pump.

I am looking at maybe a gtx3071r for quicker spool while still capable of 400-450 whp. The engine build is really kind of overkill for the power goal, but with the way the car was eating up head gaskets before I think the swap to E85 and a proper tune is going to go a long way. Previously it was running on 93 + meth injection.

[TobyB]

The block is already o rings and we will use an MLS head gasket

Is MLS going to work with o- ringing?
The traditional o- rings embedded themselves into the composite gasket,
which had enough give to make a channel while allowing the rest of the gasket to compress normally...

t

[CZero]

Is MLS going to work with o- ringing?
The traditional o- rings embedded themselves into the composite gasket,
which had enough give to make a channel while allowing the rest of the gasket to compress normally...

t

I actually had my notes mixed up. We talked about going MLS depending on how they did the o ringing and whether or not we needed a new block / head. Since the block seems fine we are just going to keep the o ringing in place and go with a composite gasket. I am kind of hoping changing to e85 and retuning will get rid of this motors tendency to eat headgaskets. I am running 23 psi on this turbo, but I still don't think it should be going through headgaskets like this.