V70 T5 How much is too much boost?

I am trying to understand this boost business!

In the 850 section there is a similar question but this i take it is with the 15g turbo?

I have the uprated engine in my `97 V70 the B5234T3 but with a 16t and HLM304map and i run on 20psi no probs. yet after 2yrs!

I have just purchased an 18T from a member on here smithson007 and am fitting this week so what would be a safe boost psi?

The bit i am trying to get my head around is the fact that the larger turbo the more air it will supply at certain revs so why doesn`t the psi have to be lowered when a bigger turbo
is fitted to be on the safe side.

As an example: if 15G up to 20psi is used and i use on a 16T 20psi surely it is more dodgy using the same psi on the larger turbo.......or am i seeing it the wrong way?

.....and then what happens with an 18T.........does the map sort anything out?

This 18T i have just bought has the straight wastegate and it came off the early V70R so what was different on that motor to keep the engine safe?

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Originally Posted by 960kg

I am trying to understand this boost business!

In the 850 section there is a similar question but this i take it is with the 15g turbo?

I have the uprated engine in my `97 V70 the B5234T3 but with a 16t and HLM304map and i run on 20psi no probs. yet after 2yrs!

I have just purchased an 18T from a member on here smithson007 and am fitting this week so what would be a safe boost psi?

The bit i am trying to get my head around is the fact that the larger turbo the more air it will supply at certain revs so why doesn`t the psi have to be lowered when a bigger turbo
is fitted to be on the safe side.

As an example: if 15G up to 20psi is used and i use on a 16T 20psi surely it is more dodgy using the same psi on the larger turbo.......or am i seeing it the wrong way?

.....and then what happens with an 18T.........does the map sort anything out?

This 18T i have just bought has the straight wastegate and it came off the older 850R so what was different on that motor to keep the engine safe?

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you are correct i bent my rods recently with 18psi on my 19t, yet with my 18t i ran 22 psi for months (then bent a rod)

can u ?

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Originally Posted by WOODY T5

can u ?

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can u?

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Originally Posted by 960kg

I am trying to understand this boost business!

In the 850 section there is a similar question but this i take it is with the 15g turbo?

I have the uprated engine in my `97 V70 the B5234T3 but with a 16t and HLM304map and i run on 20psi no probs. yet after 2yrs!

I have just purchased an 18T from a member on here smithson007 and am fitting this week so what would be a safe boost psi?

The bit i am trying to get my head around is the fact that the larger turbo the more air it will supply at certain revs so why doesn`t the psi have to be lowered when a bigger turbo
is fitted to be on the safe side.

As an example: if 15G up to 20psi is used and i use on a 16T 20psi surely it is more dodgy using the same psi on the larger turbo.......or am i seeing it the wrong way?

.....and then what happens with an 18T.........does the map sort anything out?

This 18T i have just bought has the straight wastegate and it came off the early V70R so what was different on that motor to keep the engine safe?

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It's the way the torque comes in that will kill your engine, with the 18 being larger it will produce more grunt, as said many times before it will be fine if you dont floor it low down

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Originally Posted by Jamest5r

It's the way the torque comes in that will kill your engine, with the 18 being larger it will produce more grunt, as said many times before it will be fine if you dont floor it low down

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Saying not to boot it low down is sound advice but kinda defeats the object. So basically, you sacrifice all that low down torque for some power at the top end. Most people spend 90% of the time in the mid range so to have to hover over the throttle until 3500rpm would make the car frustrating to drive. My old 850 was a pain for the same reason. Constant worry about bending a rod. The reason I find my T4 so great to drive is that the low down 300lbft gives incredible driveablility. Reving out to 6000rpm is very rare unless I feel like driving like a bell end. I think the key is to bin the MBC and have the ecu have control of the boost using a progressive (rod friendly) boost map by a competent mapper such as Tim Williams or Shark.

What keeps the engine safe on the V70R as opposed to your car is that on the V70R the stock ecu has control over boost with the bcs, Volvo will have mapped it with engine limitations in mind as they do on every car. You have overridden your ecu using an MBC so that safety parameter is now lost. If you use the BCS you will find HLM would have limited the boost to 16psi for the same very reason. Rod/engine preservation.

Also Keith about the query about psi on a bigger turbo yes you are right. At the same psi an 18T will deliver more air to the cylinders than a 16T so more chance of damage at the equivalent boost. The only minor way the 18T would reduce the chance of damage is that it will spool slightly higher in the rev range.

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Originally Posted by T5frankie

can u?

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mbc?

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Originally Posted by 960kg

I am trying to understand this boost business!

In the 850 section there is a similar question but this i take it is with the 15g turbo?

I have the uprated engine in my `97 V70 the B5234T3 but with a 16t and HLM304map and i run on 20psi no probs. yet after 2yrs!

I have just purchased an 18T from a member on here smithson007 and am fitting this week so what would be a safe boost psi?

The bit i am trying to get my head around is the fact that the larger turbo the more air it will supply at certain revs so why doesn`t the psi have to be lowered when a bigger turbo
is fitted to be on the safe side.

As an example: if 15G up to 20psi is used and i use on a 16T 20psi surely it is more dodgy using the same psi on the larger turbo.......or am i seeing it the wrong way?

.....and then what happens with an 18T.........does the map sort anything out?

This 18T i have just bought has the straight wastegate and it came off the early V70R so what was different on that motor to keep the engine safe?

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I`m running a 19T hybrid with whites and a HLM304 map, When I boot it from a stand still and the map limits the boost to 1/2 bar until the revs are over 3k then the boost climbs to 1 bar.

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Originally Posted by oblark

I`m running a 19T hybrid with whites and a HLM304 map, When I boot it from a stand still and the map limits the boost to 1/2 bar until the revs are over 3k then the boost climbs to 1 bar.

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Thanks.so I think the key point here for safety is to let the map dictate the boost as it has been set with safety in mind. If you want more than what the HLM map is set to (1bar -ish) then you will need to get it mapped again to raise the limit.

1.35 bar here from 2k on volvo rods!

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Originally Posted by WOODY T5

1.35 bar here from 2k on volvo rods!

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Fair play. I think maybe keith should try this and see if his engine can take the same? Would be interested to see if it would be ok. We have your car as living proof of how strong the Volvo engine can be and a string of broken engines and bent rods showing how weak it can be too lol

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Originally Posted by WOODY T5

1.35 bar here from 2k on volvo rods!

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That's commendable, do you run increased boost levels at higher revs as well or does it stick to 1.35 bar throughout the rev range?

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Originally Posted by mitchyboy01

Thanks.so I think the key point here for safety is to let the map dictate the boost as it has been set with safety in mind. If you want more than what the HLM map is set to (1bar -ish) then you will need to get it mapped again to raise the limit.

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Agreed, best to leave the boost control to the ecu and perhaps invest in a custom map to increase the boost a little if your not happy with it as it stands currently.

nah andy 1.35 all the way can run 1.45 to mate with no probs:) think it just shows how good the mte custom map is to

Thanks all for the replies.......and yahoooo!..... i am having a 2 1/2" Ferrita stainless exhaust system fitted tomorrow along with the 18T.......presently having my 98th childhood gotta keep my old greycells active!

I have taken off the MBC and put back my new TCV/BCS which i had only used for a hundred miles....so back to basics and see how she goes. I will play with the actuator and just learn again what to do.

Will report back what i have noticed and what psi i am gradually going to go to. May even have a vid. of the noise....if i like it!!

Keith

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Originally Posted by 960kg

..... i am having a 2 1/2" Ferrita stainless exhaust system fitted tomorrow along with the 18T.......

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We all expect a full write up and piccy's tomorrow then !

If it stops BL raining!......

Just been reading your other thread Graham about cat back exhausts......interesting...

Well had my 18T fitted today by a forum member and what an exciting day, the turbo went all very smoothly as far as fitting goes and used all new banjo washers and gaskets etc.

While he was doing the turbo i supplied his mate was doing fitting the 2.5" Ferrita cat back exhaust, although 2nd hand it is of course in excellent condition being stainless steel and not very old.

Well after the fitting went for a trial spin along the A2 in Kent dual carriageway and as i had refitted the Volvo BCS i was not impressed in 1st & 2nd gear boost but was impressed by it`s smoothness the engine sounded like a turbine and the 18T when on boost was just sounding like an aero engine but quieter....my old 16T although in good nick clearance wise when checked later was very oily and the seal had gone but it used to be noisy when boosting and sounding nothing like this 18T.....

When into 3rd it started to happen better through the BCS and the boost went quickly to the same 20psi and also in 4th held the same 20......but the smoothness is very very noticeable...

The grunt did happen later in the revs unlike my 16T which was earlier with 4 turns of the actuator on the 18T it is set at 2 turns.

The HLM 304 did not restrict the boost back to 16psi with the BCS it seems as though it has completely removed it as i can still set the boost at what i like!

I will give it a couple of days for the ECU 4.4 to adjust itself and then will probably give the actuator another turn making 3 turns from standard.

After that i may try a decent MBC but only to 20psi and from 3000revs and see what happens.

My old cheapo MBC has been set on 20psi for 2yrs with the 16T set on 4 turns of the actuator and i did like the point and shoot attitude of it
this set up now seems more power on the move higher up the rev band so of course at a higher speed not quite what i wanted but i may get the result i want by just progressing slowly and surely!!

Above all i am not sorry for the upgrade and the smoothness of the engine and the smooth delivery of the power is so really noticeable.

I struck lucky with the 18T as it had been refurbished at a cost of £389 only some 8000mls ago and i bought it for £200....the Ferrita was 2nd hand and was £200 FITTED so together with the fitting of the turbo £50 the cost was a mere £450 in total so all in all not a bad days work!

Keith

Sounds like a great day's work, and those prices are great.

You have highlighted a problem that has stopped me going for an 18t and that is it takes a bit longer to 'get moving'.....I think I'll stick with my 16t a little longer.

Glad your happy with the results.

Told you the turbo was like new :) glad someone's enjoying it.

You've got to love a ferrita. ;)
http://i373.photobucket.com/albums/o.../WP_000830.jpg

My 18t can be pretty laggy but your right about the sound, compared to my mates old t5 she sucks like a Dutch hooker! I hope a rip kit & 3" down pipe aid the spool up along with a map on mine.
Well done! :)

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Originally Posted by 960kg

Just been reading your other thread Graham about cat back exhausts......interesting...

Well had my 18T fitted today by a forum member and what an exciting day, the turbo went all very smoothly as far as fitting goes and used all new banjo washers and gaskets etc.

While he was doing the turbo i supplied his mate was doing fitting the 2.5" Ferrita cat back exhaust, although 2nd hand it is of course in excellent condition being stainless steel and not very old.

Well after the fitting went for a trial spin along the A2 in Kent dual carriageway and as i had refitted the Volvo BCS i was not impressed in 1st & 2nd gear boost but was impressed by it`s smoothness the engine sounded like a turbine and the 18T when on boost was just sounding like an aero engine but quieter....my old 16T although in good nick clearance wise when checked later was very oily and the seal had gone but it used to be noisy when boosting and sounding nothing like this 18T.....

When into 3rd it started to happen better through the BCS and the boost went quickly to the same 20psi and also in 4th held the same 20......but the smoothness is very very noticeable...

The grunt did happen later in the revs unlike my 16T which was earlier with 4 turns of the actuator on the 18T it is set at 2 turns.

The HLM 304 did not restrict the boost back to 16psi with the BCS it seems as though it has completely removed it as i can still set the boost at what i like!

I will give it a couple of days for the ECU 4.4 to adjust itself and then will probably give the actuator another turn making 3 turns from standard.

After that i may try a decent MBC but only to 20psi and from 3000revs and see what happens.

My old cheapo MBC has been set on 20psi for 2yrs with the 16T set on 4 turns of the actuator and i did like the point and shoot attitude of it
this set up now seems more power on the move higher up the rev band so of course at a higher speed not quite what i wanted but i may get the result i want by just progressing slowly and surely!!

Above all i am not sorry for the upgrade and the smoothness of the engine and the smooth delivery of the power is so really noticeable.

I struck lucky with the 18T as it had been refurbished at a cost of £389 only some 8000mls ago and i bought it for £200....the Ferrita was 2nd hand and was £200 FITTED so together with the fitting of the turbo £50 the cost was a mere £450 in total so all in all not a bad days work!

Keith

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this is why i have got forged rods now so i can enjoy the mbc rather than worry about it, much better power delivery than the boring bcs, instant boost

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Originally Posted by T5frankie

this is why i have got forged rods now so i can enjoy the mbc rather than worry about it, much better power delivery than the boring bcs, instant boost

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Have you run it is already then Frankie????:bitehard3

Interesting reading about the difference in power delivery between the 16 and 18t, I'm still unsure about weather or not to do the swap on mine, I might just wait till the turbo goes bang and then see what's about.

Decisions decisions...

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Originally Posted by M-R-P

Interesting reading about the difference in power delivery between the 16 and 18t, I'm still unsure about weather or not to do the swap on mine, I might just wait till the turbo goes bang and then see what's about.

Decisions decisions...

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If you wait until the turbo goes pop her in doors will have you in a lexus so fast your feet won`t touch the ground :)

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Originally Posted by oblark

If you wait until the turbo goes pop her in doors will have you in a lexus so fast your feet won`t touch the ground :)

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You mean she'll be in a Lexus.....Martin already has a car lol

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Originally Posted by V70 Graham

You mean she'll be in a Lexus.....Martin already has a car lol

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That`s not a car it`s a rollerskate :)

Just want to know when he`s getting one for the other foot :)

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Originally Posted by 960kg

Have you run it is already then Frankie????:bitehard3

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I around even driven it yet lol

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Originally Posted by M-R-P

Interesting reading about the difference in power delivery between the 16 and 18t, I'm still unsure about weather or not to do the swap on mine, I might just wait till the turbo goes bang and then see what's about.

Decisions decisions...

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Well my second outing......and after standing around all day yesterday and was tired on the way home today i was refreshed when going out and today seemed very much different!

The quiet drone at lower speeds seemed quieter and when i accelerated from 5mph through the gears to ***mph it does go well......i think the feel of later higher boosting is due to the Volvo BCS keeping the boost lower that i have now refitted and i am not used to it and apart from the tiredness yesterday on the way home.

Of course in 2nd at higher revs with only 10psi it doesn`t seem much until into 3rd and upwards. I did like my 16T but it did run out of puf with the MBC and this 18T doesn`t so much with the BCS.

So tomorrow i may turn up the actuator another turn see what happens and then my confidence will be better about the 18T and bending rods!

I think i have been jittery to have a good thrash, still better safe than sorry, it is a good engine i have and don`t want to ruin it just for trying to see attitude. If it does goes tit`s up then it will be converted to forged. Already have a price to do if necessary.

As regards when the 16T goes bang i am really surprised at the wear of it as the clearance on the compressor wheel / housing is the same 15 thou (apparently the accepted clearance is 10 to 20) as on the 18T which has only 8000mls on it my 16T has 162000 on it and only the oil seals have gone.

At the moment my 16T was more fun but we will see what happens with my testings!!

Yes, bending rods is alway talked about....but seems only on the original 850 T engine, the V70 i have is the T3 which has stronger rods and pistons so has anyone bent rods on this stronger engine??.....the V70R has the 18T which is the same T3 engine...

I've never heard of a ME7 engine bending a rod. I know the bottom end was upgraded at the end of 2002, although it kept the same T3 generation name, there's apparently 3 different versions of the T3 generation.

Mine (2003 with 206k miles on it) had a boost spike of 22 psi @ 2400rpm the first time it went on the rollers and didn't bend anything. Says a lot for the newer engines.

Exhaust looks real nice by the way.

you wont bend any rods with a bcs, so do't worry, i personally dont like the build up of boost with a bcs it takes too long, and i think its urban myth that some t5 engines have stronger rods and pistons, the 1st engine i bent a rod in was a 1998 v70r

weren't you running 22 psi on an 18t?

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Originally Posted by M-R-P

weren't you running 22 psi on an 18t?

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yeah mate on a 200k engine lasted for about 3 months at that boost

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Originally Posted by M-R-P

I've never heard of a ME7 engine bending a rod. I know the bottom end was upgraded at the end of 2002, although it kept the same T3 generation name, there's apparently 3 different versions of the T3 generation.

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theirs alot more than 3 version. When Volvo revised the N engine there was no definitive swop over to the new components, the upgrades were fed in as you say between 2002-2003. So some engines may have the RN's light crank, but not have the thinner valve stems or vice versa depending what they had at the time of building

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Originally Posted by T5frankie

yeah mate on a 200k engine lasted for about 3 months at that boost

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kinda explains the eventual bent rod really, metal fatigue and all that.

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Originally Posted by p fandango

theirs alot more than 3 version. When Volvo revised the N engine there was no definitive swop over to the new components, the upgrades were fed in as you say between 2002-2003. So some engines may have the RN's light crank, but not have the thinner valve stems or vice versa depending what they had at the time of building

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whatever was rattling about in the parts bin then lol

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Originally Posted by M-R-P

whatever was rattling about in the parts bin then lol

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basically yes lol

Ok I have not done much with the whiteblock family but know enough about redblocks.
You never start with a 9mm rod engine and always use a 13mm rod engine to start with. With the whiteblock I would say after an exhaust and inlet upgrade simple stage 1 tuning the very next step should be a set of rods. They might not be cheap but its a lot cheaper to fit uprated rods before you kill and engine.
With the redblock what kills engines is running to much boost on a small turbo. Once you pass the limit for the turbo you will still get more pressure but the heat build up can actually give you less oxygen and therefore less power. The bigger the turbo (within reason) the more boost pressure you can safely run.

With saying that my last was running a good 18PSI and never had a problem other than getting any traction is 1st 2nd or 3rd, rods were on the cards so I could take it a little further

Just to update this little lot.........i have now fitted and been running the MBC for a few weeks and at 20psi the same as the standard 16T which was in use for 2yrs.

But where the 16T gives up the 18T carries on well into three figure speeds!!......and getting there feeling is just as good if not better!

I did like the point and squirt attitude of the 16T with the HLM 304 map but the 18T seems to do it in more building up style than aggressive and petering out style.

This thing about low down WOT and damaging torque before 3000revs......ok i understand it, but me being an old school style rally driver from the past... to be damaging your`e in the wrong gear!

3000revs in 2nd is only 30`ish mph so therefore it is ok to use WOT at the required non damaging revs.....if one wants to accelerate no good treating the motor like a bus or lorry with a diesel engine just drop a gear and you are in the correct rev range so no bother........so why owners carry on about that is no good being a restriction on 3 or 3500 revs before you floor it i don`t understand that aspect, as one is not driving properly!

As usual just my own opinion!

just a matter of time mate at 20 psi, pete bent a rod with his 18t