Hi guys,

Posting this on behalf of my friend Rob who just bought an '87 Volvo 740 Turbo manual wagon. Head gasket is gone, so this is one of those "while we're at it... " situations where it would be nice to make improvements.

Thanks to Matt the focus will be to just improve air flow. Would also like to keep repair time to a minimum, so looking for the following:

• TD04HL-16T straight flange with downpipe ideally

• 531 head

Cur currently had a 530 head, with a tired TD04-12? turbo in it. Going to keep the cam stock for now, and will hopefully implement some of Craig's combustion chamber improvements, as well as a 3 angle valve job before reassembly.

I'll also bug Rob to chime in and maybe to do a bit of a project build on this car as it's pretty neat car that should clean up REALLY nicely.

Thanks,

Rabin

If the power goals are modest, and they should be if he's sticking with the 87 block, don't worry about a 531 or getting fancy with head work.
Update the exhaust manifold, turbo, exhaust and that will unlock most of the restrictions until he gets a hotter cam. Even with the stock camshaft that will be maxing out the stock fuel system and potentially blowing up the transmission, if the block hasn't already vented.
I'd look for a proper (90+)long block, or complete engine if I was him.
All that said, I've been out of the Volvo game a long time so...

Thanks for the input! I've only absorbed the odd red block details from reading about other peoples builds, but now that I'm helping Rob with the replacing the head gasket on this 740 I'm trying to remember the details.

531 head was more of a 'hail mary' as it'd be nice to have a second head rebuilt and ready to install, and since the 531 was supposed to be better that's what I threw on the list. Car came with a 90+ manifold, with a stock Garrett attached that feels good, but it didn't come with any lines (No idea how involved it is to switch from TD04 to T3), and I'm not sure the current downpipe would work on the T3 either. "while we're at it..." dictates if the turbo needs rebuilding, and the T3 needs a new downpipe AND new lines, then a 16T with a big straight flange might be the better choice as it should flow much better, and just need a new downpipe. I've only experienced a 16T in a 98 V70 T5m and I was really impressed with the quick spool and power delivery. I also quite like the TD04 turbos...

Computer is going to be stock for the time being so it will just move more air at stock boost settings for now. If we can line up a 16T for the install then I'll rebuild it if needed and port the manifold and exhaust housing like I did on my 00R... (I quite enjoyed that...)

All that said this really is just a stock+ build trying to improve air flow as much as possible where we can. Might not have super high power goals, but the improved efficiency should be a secondary benefit. Reliability will be a definite concern though so if a 16T is going to be too much even at stock boost levels then we can rethink, or lower boost further until a suitable built motor shows up. (Right Rob?)

Rabin

If you can find a 531, which I doubt, it will cost way more than it's worth, for Robs needs. The stock head with bolt ons, will flow more than enough to blow up the stock rods, clutch, transmission.
These are tractor motors, built for more torque than hp (notice every variant has more torque than hp). Improvements to flow are mostly going to benefit power above 4000. Does Rob spend much time in that rpm range?
Just get a good stock 530, clean it up, do some mild porting if you want and focus on getting air out of it as efficiently as possible. I bet the 90+ manifold hasnt even had the collector ported.

Great advice!

What's your thoughts on the 16T then? Too much turbo? Better to use the stock Garrett and find / change the necessary lines? Rebuild the stock TD04-12? (It's a 12 something)

This is mostly about fixing it right and making the best bang for the buck improvements while we're at it. Reliability is more important that power, but it's still nice if the car has some giggle factor in it when it comes on boost. (That last part might be more my preference than Rob's...)

Rabin

Athal's right on the money. If you can find a 405 head, which is far more likely, you can gain most of the benefits of the 531 and they were pretty common in Canada at one point. The only 531s you're likely to find in NA are from boats, so they're often rotted out or have that anode ring in the #4 exhaust port. The 405 only came with K-jet so you'll have those injector holes to deal with, but you'll have those injector holes to use if you want to also use the K-jet intake manifold which has a bigger plenum and larger diameter runners. Again, under 6k RPM you probably won't see much benefit, but you also won't lose much where the engine is happy either. But the 530 is a drop-on, bulletproof, common-as-dirt head that'll more than satisfy a small-rod, LH2.2 engine.

I still say to stick with the stock Turbo cam but if you do upgrade to anything I wouldn't go beyond the Enem V15T or IPD Turbo cam, same-same. They maintain most of the bottom end but open up the top some more (beyond the 6k fuel cut), and if you've already uncorked the head/manifold/turbo/exhaust that'll be the next step. It's a quick & easy swap with the engine in the car so don't bother spending that money now, I say.

So what about turbo for a max 6K redline? Quick spool and not strangling the motor at redline is sufficient for sure. Be much happier with a nice flat torque curve with excellent drive ability than shoot for all out power.

Already have the 90+ manifold, that also has a decent feeling stock T3 on it, but no lines came with it except the hard lines bolted to the turbo. I'll try to get a picture of it, or get Rob to post pictures of what we have to work with.

530 head sounds like the way to go, so will likely just get this one done since it's what we have. Any recommendations for decking it? Matt already recommended Ehlring gasket set, and 3 angle. I was just going to unshroud the intake valve a little following the basics of what Craig showed in his 242 engine build, but not nearly as pretty, and do some port matching on intake and exhaust sides. Will also port 90+ outlet and exhaust housing.

Only uncertaintly now is what turbo to go with - So thoughts and recommendations are appreciated. Guy on FB has a 16T with a straight flange for $150 which is what I thought would be a good fit - but maybe it's too much turbo? Stock TD04 on it looks really restrictive - but I've never even driven a 740 Turbo.

Rabin

I think a TD04HL-15G from a stock T5 850 would be a good choice. That car makes ~225 hp stock, so does the 5 speed Saab 9000 Aero 5 speed which comes with a similar turbo. I think that's what's on Craig's B230FT at the moment. I've never driven it myself, but I've been in it when he's got the fizz and it's quite exhilarating. Certainly not lazy.

Sorry for the delay on getting back to this thread!

After all that discussion it became clear that the best way to proceed is the path of least resistance. So options now are to just rebuild the stock turbo and source a better solution later, or ideally - just use the Garrett turbo )as is or rebuilt), but what I'm to get from the experts is if we have everything to install it. See attached pics for reference:

I've read "the lines are different" when swapping to the Garrett, but this does have hard lines attached - just not sure if what we have is all that is required - Or if there are other specific parts.







Goal is to be able to get it apart, have head redone, and then installed so the car is only in the garage a week or so...

Thanks!

Rabin

You seem to be missing the oil feed line. IIRC on the Garrett it's a 2 bolt flange while on the MHI it's a banjo like you've got. I don't remember what's on the 12B that's in the car.

Make sure the water pipe under the exhaust mani is dipped down to clear this manifold - IIRC the earlier straight style will fit the early manifold but not the 90+. I think all turbo redblocks have the dipped water pipe and maybe my red flag is coming from when I used the wrong parts from the B23E in one of my builds.

I can't guarantee that the downpipes will mate up. Almost certainly not, since the MHI oulet isn't concentric with the turbine shaft while the Garrett is. I can't remember what the 12B outlet is like, but I think it's concentric?

I also don't remember if the 12B has an integral CBV like your 13C. I think it does. I know the Garretts used an external Pierburg CBV bolted to the head, and consequently different turbocharger inlet & outlet hoses (ones with the bypass hoses built in). I think the diameter and shape of the inlet & outlet hoses are the same otherwise.

Sorry, I know I'm not giving you definitive answers here, just things to watch out for, but it's been a while since I've been familiar with all of the layouts.

Clarity is a wonderful thing - Dude said the turbo attached to the 90+ mani above was a Garrett and I didn't even think much about it. Was thrown in the car and didn't really look at it again and just assumed it really was a Garrett!

You picked up on it right away, and seeing it properly now with the banjo bolt feed line and the internal c-clip holding the compressor housing - it's totally a MHI turbo. D'oh!

So this is a 13C then? This should then be a direct bolt on for the 12B then I'm guessing should it not?

Thanks!

Rabin

I can neither confirm nor deny that it's a drop-in. I'm not certain the offset between the axis of the turbine shaft and the downpipe outlet hole is the same between the 12B and 13C. I would assume not, since the 12B is a TD05 and the 13C is a TD04.

One thing you should consider is opening up both the manifold and the turbine inlet. See here what Craig did: viewtopic.php?f=13&t=1642&start=330

Please politely ignore the polishing he does to the outside. The man's got issues. Just nod and smile, boys... nod and smile.

The down pipe isn't as big an issue if we can find the flange as it would be easy to get it done at a muffler shop - was mostly wanting to make sure the center section was going to connect to cooling and oil feed and return lines. I've got left over 13G turbo parts from my 00R build, but it's got the angled exhaust housing which won't work as nicely in the RWD cars.

Will definitely port match the housing to turbo housing, as well as head to exhaust ports - but the exterior will likely just get blasted with a possible ceramic powdercoat.

Rabin