M90 Race Car Engine Build (Now with more M54!)

E28 technical advice asked and given! Troubleshooting, modifications and more.
LeiseyJr
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Re: M90 Race Car Engine Build

Post by LeiseyJr »

nik77356 wrote:As I have previously stated in the original post, I would like to run a B35 Oil Pan and Pump. I want to do this for multiple reasons. The B35 Oil Pan seems a bit more conducive to adding baffles, as well as the B35 Oil Pump providing more pressure due to the smaller drive gear diameter. The biggest issue I see, is that the block I am using does not have provisions for the oil pump chain tensioner. Based on this thread: http://www.mye28.com/viewtopic.php?t=119354 I should be able to run the B35 Oil Pump using part number 11 41 7 577 655, as this chain has 44 links, along with the correct number of shims to get chain tension correct (part number 11 41 1 250 562).

I don't believe there are any differences in the way oil gets from the pump into the engine between older M30/M90s and the M30B35. Has anyone experienced anything different? I will likely mock this up later this week.
The pump would not just provide more pressure overall just more pressure sooner. The pressure gets capped off at a certain point. Unless the "Wastegate" on the b35 oil pump pressure is higher then the b34. I can upload vid of where B34 oil pressure is capped off if need be. Usually in higher rpm applications you want to slow things down since the engine is overoiling or like on SR20's they usually put a larger water pump pulley because it starts spinning the water to fast. You can have too much oil pressure, and if you are already being overoiled then a B35 pump would just make that worse.

I also think the head restrictors might not be needed, just a good way to catch the oil. Although your motor will be a track only motor, so unlike me you won't care about oil delivery at idle as much. Hell you could just vent it to atmosphere at the valve cover like they used too leave all the oil in the head. You have to remember that M10 race motors run to 8,000-9,000 rpm. Do 7,000rpm M10 build get block restrictors? I would call Ireland or Korman and get their take on what you should add.

"wastegate" or relief valve I'm talking about
https://www.youtube.com/watch?v=zOZHJQ69Oag
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

Bit of an update:

Cylinder Head and Engine Block have been at the machine shops almost two weeks now. I should get the Cylinder Head back on Saturday.

Engine Block Machine Shop called me yesterday and said we need Piston Rings. Well..... that presents a problem. Nobody makes Rings for these things anymore, at least that I can find. I was really hoping to not have to get a set of Pistons made for this engine, but it is looking like I may have to.

Does anyone know of a source for stock bore M90 Piston Rings?
VintageRacer
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Re: M90 Race Car Engine Build

Post by VintageRacer »

Call Kozman or VAC.
Shawn D.
Beamter
Beamter
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Re: M90 Race Car Engine Build

Post by Shawn D. »

VintageRacer wrote:Call Kozman...
Korman?
WVe28
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Re: M90 Race Car Engine Build

Post by WVe28 »

Wallothnesch has everything for the M90 including piston rings and head gaskets.

https://www.wallothnesch.com/en/motorte ... 11-29.html
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

Well, for $500 just for a set of rings, I'd rather just go ahead and double that, and get a whole new set of custom pistons.
BuzzBomb
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Re: M90 Race Car Engine Build

Post by BuzzBomb »

As someone with actual experience with your situation, as I stated in the other thread, the restrictors are there to slow the flow of oil into the head, not starve it. All race engines I build, whether M10 or M30 get restrictors. Period. Never damaged valve train from oil starvation. Also, M10/30 engines used in competition typically don't use the OEM valve cover to intake EGR hose, it's catch-can time. As far as the "B35" oil pump is concerned, the driven shaft is the same as all M30 oil pumps that have a single center held gear. The difference is diameter of the chain gear and the chain length. Late B34 and B35 blocks that use a tensioner have a smaller gear and longer chain. M30 based blocks before '87 share the same length chain and gear size, so just use the earlier hardware on whatever pump you use, along with the B35 pickup and pan. Another thing you can do is with the head totally disassembled, you can open up the drainage passages in the head and "port match" the gasket to the drain holes if necessary to help oil exit more efficiently. I would not suggest making any changes to the block itself, though.
BuzzBomb
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Re: M90 Race Car Engine Build

Post by BuzzBomb »

nik77356 wrote:Well, for $500 just for a set of rings, I'd rather just go ahead and double that, and get a whole new set of custom pistons.
The last M90 set I got were from Deves. A couple hundred for the set. Call them on the phone for faster service. I had mine in less than a week.
BuzzBomb
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Re: M90 Race Car Engine Build

Post by BuzzBomb »

WVe28 wrote:Wallothnesch has everything for the M90 including piston rings and head gaskets.

https://www.wallothnesch.com/en/motorte ... 11-29.html
Unfortunately, unless you wanted to spend some money on a "Cometic" style gasket, which you can order in whatever bore size you want, W&N is one of the few places that an M90 head gasket can be found. Just buy the head gasket though, not the whole kit. The rest of the engine gaskets they offer are pretty poor quality from what I've experienced.
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

BuzzBomb wrote:
nik77356 wrote:Well, for $500 just for a set of rings, I'd rather just go ahead and double that, and get a whole new set of custom pistons.
The last M90 set I got were from Deves. A couple hundred for the set. Call them on the phone for faster service. I had mine in less than a week.

Holy shit, this is the answer! I talked to them, and they'll have a set made for me by the end of the week, if not sooner! You rock!

On the Head Gasket, Levent at GutenParts is sourcing one for me.
WVe28
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Re: M90 Race Car Engine Build

Post by WVe28 »

BuzzBomb wrote: M30 based blocks before '87 share the same length chain and gear size, so just use the earlier hardware on whatever pump you use, along with the B35 pickup and pan.
I did exactly this with a B35 pump and pan on my M90 block. Seems to be functioning appropriately.
BuzzBomb wrote: W&N is one of the few places that an M90 head gasket can be found. Just buy the head gasket though, not the whole kit.
Yup. I had a helluva time finding the M90 gasket until I found out about W&N. I ordered the gasket from them and had it within a week. My bore is 94mm and it fit fine. That was my only concern, initially. The gasket is 1mm overbore (so 94.4). I ended up getting a full top end gasket kit for a B34 and bottom end for a B28/B30 from FCP just because I was too lazy to source everything individually.
VintageRacer
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Re: M90 Race Car Engine Build

Post by VintageRacer »

I applaud this thread for highlighting that you can be frugal in building a hi performance engine for track driving. However for those on the sidelines reading please don’t confuse this with what it takes to build a full competitive engine like the old Group A M30’s. Custom pistons were a minor expense and may be false economy in the long run. But like any engine build it’s all about the end goal and the funds available. For me custom pistons meant I could go to the S38 144mm rods and allow any compression ratio and chamber profile to improve quench. Granted I trusted my engine builder who is one of the top M10 race engine builders in the US. I think this also highlights how experience is worth the money. I’ve built plenty of VW air cooled motors and Datsun engines but at no point do I think that qualifies me to build a racing M30.

I haven’t run my engine yet but I’ll post up when she’s installed and on the dyno. It won’t be what our 4.0L S38 makes but it will be historic and I will rev the piss out of it because it costs 1/3 of the S38!!
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

A bit of an update, I was able to source the Piston Rings very easily once I knew where to get them. Thanks for the source, BuzzBomb! Levent is working on getting the Head Gasket, but apparently his supplier is giving him some troubles with getting it. The Bottom End is done, the Cylinder Head has been slightly delayed, as the machinist's wife has gone into the hospital. Hopefully she gets better soon, for their sake, and also my Cylinder Head's sake.

In the meantime, to try to not miss another race, I put the old B34 back in the car, and converted it to M1.3. In this process, I now have a pretty large stumble off idle under zero load that I did not have before. The only changes I have made are converting it to M1.3, and adding a super lightweight flywheel (8.5lbs). I have not yet checked for vacuum leaks (haven't been able to snag the smoke machine from work yet), but if I unplug the TPS while it is idling, and then rev the engine, the response is totally normal, and then the engine will idle high, but also still respond fine to throttle inputs. With everything plugged in and the engine running under no load, it will respond fine to slow throttle. We'll see what I can dig up, hopefully this weekend.

In the meantime, since I couldn't get the car running for the race last weekend, I borrowed my good friend's SpecE46, which very easily slots into ST5, the class I run. Here is a video of Saturday's race: https://youtu.be/_FQixB-X8SU
athayer187
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Re: M90 Race Car Engine Build

Post by athayer187 »

I had a similar issue when I swapped M1.3 years ago. The issue was my TPS. There should be two times it switches - just off idle, and WOT. I can't find the pinout quickly here at work, but I'd just get a new TPS and be done with it. FWIW - the spare I had on the shelf didn't switch at WOT, so I ended up buying new.
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

athayer187 wrote:I had a similar issue when I swapped M1.3 years ago. The issue was my TPS. There should be two times it switches - just off idle, and WOT. I can't find the pinout quickly here at work, but I'd just get a new TPS and be done with it. FWIW - the spare I had on the shelf didn't switch at WOT, so I ended up buying new.
That was one of my few things to try. Although, everything worked fine when it was on M1.0 with the same TPS, and then I swapped over another known good TPS (allegedly, it appeared to be operating properly when that car last ran), from the car the M1.3 Engine Harness came out of, but I will order a new one and see.
athayer187
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Re: M90 Race Car Engine Build

Post by athayer187 »

nik77356 wrote:
athayer187 wrote:I had a similar issue when I swapped M1.3 years ago. The issue was my TPS. There should be two times it switches - just off idle, and WOT. I can't find the pinout quickly here at work, but I'd just get a new TPS and be done with it. FWIW - the spare I had on the shelf didn't switch at WOT, so I ended up buying new.
That was one of my few things to try. Although, everything worked fine when it was on M1.0 with the same TPS, and then I swapped over another known good TPS (allegedly, it appeared to be operating properly when that car last ran), from the car the M1.3 Engine Harness came out of, but I will order a new one and see.
Listen for "click" and probe pins with a volt meter. Something should change just off idle (some combination of pins will open or close continuity, I honestly don't remember!), and something should change at WOT.
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

I finally got the engine block back from the machine shop!

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LeiseyJr
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Re: M90 Race Car Engine Build

Post by LeiseyJr »

Looking good!
djjerme
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Re: M90 Race Car Engine Build

Post by djjerme »

I'll pull the valve cover off my race motor this afternoon and get a pic of how we modified it to fix the smoke issue. My buddy has done the mod on a few race M30's and it cures the issue; at least after hours of racing I haven't seen any smoke like it did before the mod...
nik77356
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Re: M90 Race Car Engine Build

Post by nik77356 »

djjerme wrote:I'll pull the valve cover off my race motor this afternoon and get a pic of how we modified it to fix the smoke issue. My buddy has done the mod on a few race M30's and it cures the issue; at least after hours of racing I haven't seen any smoke like it did before the mod...
That would be fantastic! Thank you!
tschultz
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Re: M90 Race Car Engine Build

Post by tschultz »

Curious to see the details of this^^
djjerme
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Re: M90 Race Car Engine Build

Post by djjerme »

Here y'all go.

It's pretty simple - just silicone on the edge and then two small bends on the sides to allow the accumulated oil to drain in a better direction. Again, this was done on my own car, and the team Chumpcar - which it lasted through a 36 hour race in Spokane, along with all the other races until the car got destroyed. I'll admit, not the prettiest solution - but racing is not always about looking good, it's about finishing. ;)

Image
LeiseyJr
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Re: M90 Race Car Engine Build

Post by LeiseyJr »

djjerme wrote:Here y'all go.

It's pretty simple - just silicone on the edge and then two small bends on the sides to allow the accumulated oil to drain in a better direction. Again, this was done on my own car, and the team Chumpcar - which it lasted through a 36 hour race in Spokane, along with all the other races until the car got destroyed. I'll admit, not the prettiest solution - but racing is not always about looking good, it's about finishing. ;)

Image
I love you. I will be doing this.
adam_poll
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Re: M90 Race Car Engine Build

Post by adam_poll »

Does the silicone fully seal off that side or just the edge? I'll also be trying this to avoid possible future black flags for clouds of blue smoke

Thanks, Adam
BuzzBomb
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Re: M90 Race Car Engine Build

Post by BuzzBomb »

Or you could just put restrictors in the block's oil passages to the head to reduce pooling, which is the primary cause of what you're trying to fix.
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