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Aug. 30, 2011 8:17 a.m. Murphy New Reader

I bought a 90 740 Turbo sedan yesterday, automatic. Runs strong, clean southern car. But has some interior cosmetic issues and the bumpers are pretty beat. Any Michigan Volvo enthusiasts looking to get rid of any parts please let me know. The front seats are bad, and numerous little things around the interior. I think I need to completely replace the front air dam as well. Bumpers probably just need a whole new paint job.

Where do I start on turning up the juice? Ive never owned a turbo vehicle before. Im not looking for 300 horsepower. But a little bump would be nice.

thanks Nick
Aug. 30, 2011 8:31 a.m. foxtrapper SuperDork

Increase boost.

Non-guaranteed technique that I used quite well was to simply disconnect the regulator line and just run maximum possible boost.

Now I only 300k miles out of that car before I sold it. Many folk insisted the engine would grenade this way, but in all those years, it never did.
Aug. 30, 2011 9:31 a.m. mad_machine SuperDork

useless without pics....

but sounds like a good car
Aug. 30, 2011 9:35 a.m. Murphy New Reader

Gotta clean it first...
Aug. 30, 2011 10:28 a.m. DukeOfUndersteer SuperDork

congrats! Welcome to the Volvo club! I'm on my second, working on my third (a 1985 240 Turbo )
Aug. 30, 2011 10:30 a.m. mad_machine SuperDork

Murphy wrote:

Gotta clean it first...

no excuse.. I have not washed my saab and I posted pics
Aug. 30, 2011 12:25 p.m. donalson SuperDork

congratz... '90 should give you the lh2.4 so much better electronics...

head over to turbobricks.com and snoop around you'll want to do whats called "stage 0" before you do any mods... aka get it to where it was when it left the factory before you do more... basically a big full tune-up,

cap/rotor, plugs (stick with copper OEMish stuff... pretty much consensus that higher end is a waste, just replace em every other oil change or so), plug wires, fluids, filters, fix any oil leaks, replace or clean out the breather box (sits under the manifold... the hose going from the intake hose goes to it) replace the gasket under the oil cap if yours is leaking/spraying out from the cap (you can usually flip them at least once if you are on the cheap), also a good time to replace all the hoses and belts under the hood (vac and coolant) also will want to pull the codes from the car to make sure everything is right http://www.brickboard.com/FAQ/700-900/EngineOBDCodes.htm#GeneralNotesonOnBoardDiag...

once you get that basic kind of stuff done then it's time for some fun :)... a MBC (manual boost controller), GOOD boost gauge (not the junk OEM stuff) and an a/f gauge

anyway read over this... it covers pretty much everything :)... and remember... 200rwhp in these cars is pretty stinkin quick... http://web.archive.org/web/20040624005408/mcbrooms.com/volvo/fast700.htm

welcome to the club and enjoy the new toy :)
Aug. 30, 2011 1:16 p.m. pilotbraden HalfDork

I have a 242 turbo sitting in a field in Argentine MI. What do you want?
Aug. 30, 2011 1:52 p.m. Streetwiseguy Dork

foxtrapper wrote:

Increase boost.

Non-guaranteed technique that I used quite well was to simply disconnect the regulator line and just run maximum possible boost.

Now I only 300k miles out of that car before I sold it. Many folk insisted the engine would grenade this way, but in all those years, it never did.

I've seen them blow up when the wastegate actuator hose splits, although the overpressure shutdown switch makes them very scary to drive, as your eyeballs bounce off the windsheild and the back of your skull.
Aug. 30, 2011 2:50 p.m. foxtrapper SuperDork

Well, truth be told, mine had a section of the wastegate hose hidden under something that had rotted away. I didn't discover this for years, and god only knows how many years it had been that way before I bought it.

The car had a genuine + package installed somewhere along the line, the hose for that was run to the wastegate hose, after the rotted section. So neither it nor the wastegate ever saw the boost. Only the engine and the gauge saw the boost.

The car very sensitive to gas octane. You had to run premium gas in it, otherwise the knock sensor would drop it onto its nose after the boost started to really build.
Aug. 30, 2011 11:39 p.m. Murphy New Reader

There is an aftermarket boost gauge but it still doesnt show much detail, bounces between 0 or 30 pretty much. What does the 242 share with the 740? I might need seats, bumpers, glove box, ill make a list.

What is a safe amount of boost on a stock engine for this car?
Aug. 31, 2011 1:40 a.m. donalson SuperDork

you've got the bigger rods i belive (think that was a 90 addition... along with the better turbo manifold and fuel injection)... but the real answer to the how much boost question is... untill you start getting detonation... with the stock 13c iddy biddy turbo you've got there is no point in going beyond about 13psi or so... just blows lots of hot air after that...

if you didn't read the stage 0 bit... you'll gain a lot more HP doing that many times then cramming more boost down it's throat...

I ran about 13psi on my 1st volvo (86 765)... everything stock except the MBC and gauge :) any higher and it would spike and hit boost cut which as mentioned above hurts... POWWAR and then nothing... lol...
Aug. 31, 2011 5:57 a.m. 11110000 Reader

Just echoing the Stage 0 comment - make sure you've got a solid base to start from.

After that, a MBC can give you better boost response as well as higher boost, making the car a lot more fun. I ran 14PSI on my old wagon (larger turbo), but I had the skinny rods which eventually gave in. 13PSI is probably tops for the little 13c, but the late models like yours with the Turbo + kit would do an honest 192HP and well over 200lb-ft.

Next step would be to get a larger turbo, grind out the manifold flange (it's sized for the tiny TD04 but can be enlarged quite a bit) and mate a full 3" exhaust. All this will give you some solid and reliable horsepower without having to worry about breaking things or performing major system upgrades on any of the other components.
Aug. 31, 2011 7:38 p.m. BoostedBrandon Reader

Gonna hijack yer thread here....

One thing I've noticed is that most turbo models I've found are autos. Now most other cars an auto will suck all the fun out of driving, is this the same thing?

The thought of the practicality of a wagon, with the woosh of a turbo makes me smile. Someone like me, not totally partial to which wheels drive it, what's the model to shop for? With full intentions of causing tire smoke.
Sept. 1, 2011 9:33 a.m. dculberson HalfDork

Most of the turbos are auto, unfortunately. I don't have any experience driving a turbo Volvo with a manual but can say the auto detracts from the experience. It's not horrible but definitely gives you the "punch it - pause pause - there it is" feeling. The good news is the manual swaps are pretty straightforward and widely available. If my wife doesn't fall in love with our turbo brick that's my plan - swap to manual.
Sept. 1, 2011 9:59 a.m. dj06482 HalfDork

With Saabs, the auto/turbo is a great combination, especially with the Sport button on!
Sept. 1, 2011 11:18 a.m. dculberson HalfDork

That's a good point. Mine is a '96, and I feel like the electronics to the transmission just aren't aggressive enough. The LS400's auto is a lot better, much freer with the downshifts.