Hey Guys, just bought my 2nd glt, a 98 s70.

Had a few questions about some mods for it. I just bought a MBC and boost gauge. I was wondering what the maximum safest pressure is to run on a stock motor on 93 octane. Assuming I keep an eye on the boost gauge for spikes. I did search but I couldnt find any solid answers.

Also, what would be the next best bang for your buck mod after that? EST intake?

And, if anyone knows, how much can I expect the car to wake up with a few more psi?

 

Bang for buck mods:
-downpiping
-catback
-ECU upgrade (do this after all other performance upgrades)
-R manifold?

 

13 PSI on the stock setup should be ok as long as your stage 0 is solid.

 

15 PSI is safe on the GLT's, that is what I am running. No more though then 15 PSI.

Your car will wake up nicely if you boost it to 10 PSI. Even 12 PSI will be nice.

A short ram intake like the EST or IPD USA's wont net you much if any power gains. Just sound and under the hood looks. I'd say stick with the K&n panel filter and or create your own CAI system.

Before you mod do STAGE ZERO first. Can be found in the General Volvo section of this forum under the VOLVO FORUMS RESOURCES THREAD.

 

Sweet, thanks guys. Im pretty excited. Stage 0 is good. Just did timing and rebuilt the head.

How much could I expect to pay to have an exhaust shop make me a 3'' DP?
Or do any vendors make some that arn't outrageously expensive?

Also, If i wanted to run a BOV, I heard of cutting the Intercooler rubber hose and sliding/clamping it inside of the hose. Is that entirely too ghetto? Would running rich for a second cause any problems?

 

A custom shop depending on material I would expect to pay $300-$900 for a custom downpipe. You will want 3" mandrel bent piping for the downpipe and catback system.

Premade from a company your going to pay $700-$1500.

I wouldn't run a BOV. If your automatic it will only go off when you let off the gas. It wont give you any performance benefits. All you will get is the sound. Which at first is addicting. I had one, then sold it because it got annoying. The way you suggested is the ghetto way of doing it. If you have to have one have an Aluminum flange welded to the upper intercooler pipe, the one that goes over the engine. Then the BOV goes on that flange and you run a vacuum line and your set. Running RICH for that short period of time wont cause issue instantly, but over time it could. Note I said it could, not it will.

 

Straight, I appreciate you help. You wouldn't happen to know off hand of any write ups specific to s70s for MBC or Boost Gauge Install would you? Im sure I could figure it out looking at general instructions but it might be nice.

 

No sorry.

I don't recommend a MBC anyways. But that is just me. I recommend getting an ECU upgrade.

 

What are the downsides to an MBC? Would you still think 12 psi range would be ok on the stock tune? I know im a noob, in volvo terms anyway, haha but Id really rather not blow my motor up. I appreciate you help.

 

Both of my 850's are running over 10 PSI on stock tunes. I am actually running 14 PSI on the R stock tune and AFR's are fine kind of. A little on the rich side which is way better than lean. But I have a leak I cannot track down. The wifes car is running 12 PSI on a stock tune for over a year now and nothing wrong.

With a MBC the boost is alot smoother and is alot quicker under slight acceleration.

I like the way the MBC works the boost. I will always have one on my turbo cars as long as it can be done.

 

Sweet. Another question--Ebay has some really cheap FMICs for around 60 or 70 shipped. Would it be worth my time to try and fab up some piping and install one? I feel like the stock intercooler gets heat soaked pretty fast. How much more boost should I be able to run? a lb or 2?

 

Also, it looks like my mbc and gauge is coming in sometime next week. Look out for videos and pictures of the install.

 

Don't cheap out on the EBAY FMIC's. An FMIC is a great way to upgrade, just do it properly. I know people on Volvospeed have done this and used EBAY piping which was like $90-$160 and then bought a intercooler for maybe $100 or so. $250-$500 will make a decent setup.

 

Will any vac line off the intake manifold work for my boost gauge?

 

Yes it will.

 

I know this is an oldpost but on the glts and the 850s they have a nice recirc valve and ipd makes an upgraded spring to help improve boost levels. Also adding a nice cone type filter will let you hear the recirc pop off.. sounds way better then a bov or "show off valve" to me. I do have a performance question though if I decided to run a mbc on my lpt what would be the max boost I could make with the little turbo. I have a 8g from a s40 and that little thing makes 10-13lbs easy and fast. I know theese lpts are just a tad big bigger 12 g or.somthing like that but I know there a decent size and I'm thinking it should be able to produce at least 12-14lbs of boost. Any input is would be super helpfull. Volvo for life!

 

in short, small turbo, fast spool for low end power loose it in the upper end unless you have high boost. The new Nissan Juke does this 20 PSI and a flat power curve.

larger turbos are capable of higher boost, but are slow to spool. Example, look at and turbo diesel truck. 300psi (sometimes more) compression, and built to handle 25PSI and when tuned even more.

Actually just replacing the muffler with a straight thru (magnaflow) will reduce back pressure enough to give a noticeable difference. But, jump pressure up to around 14 regulated pressure and I would guess an instant 40-60 HP gain at the crank. Cut XXX number by roughly 30% for FWD and 40% for AWD to get a guestimate at whats going to the wheels.