850 r ecu in t5?

[Bigsi15]

Quick one guys, can an 850r ecu be put directly into a t5 for a slight performance increase?

Thanks in advance!

[nottsgreent5]

Yip should be a straight swap bud

[Bigsi15]

Ah cool and would it give the r performance too? Thanks for your reply

[Bigsi15]

Also would it matter if it was from an auto car going into a manual?

[Shinsplintz 101]

Putting a standard 850R mapped ECU [AUTO] into a T5 should theoretically give you a 15hp gain - 240bhp in a R Auto - they both ran the same turbo [15g] - you might want to put a set of white injectors in to be safe.

Putting an auto ECU in to manual will be fine - but you may find flat spots in the power delivery. You cant do it the other way around, manual into an auto that is.

All the best, Morgan

[Saaamon]

Manual ECUs hold on to the revs unlike autos.

[MoleT-5R]

If your thinking of buying an 850r ecu to go in your t-5, I would recommend trying it first before handing over your hard earned cash as sometimes some 850r/t-5r ecu's will not start some t-5's, If you've already got one you may be lucky and it may work for you, I have an 850r ecu here that doesn't like working in our gul t-5r but will work fine in the later olive t-5r, this could be due to obd1/2 differences and as mentioned above an auto ecu will work fine in a manual car but not the other way around

[claymore]

As Aid says, if your car is a has the obd11 port under the coin holder, it will work, if you have the diagnostic port in front of the ecu under the bonnet, it won't work.

[Shinsplintz 101]

Plus 1 to the above. I have a hlm/Rica 304 in mine that will run on every car I've tried in, however I also have a similar ECU that won't. Funny old business swapping about ECU - thinks it something to do wit the immobiliser.

[Bigsi15]

Thanks for the replies guys. I have (I assume) an obd 2 port below the radio in a 96 model year car so guess will have to see, got one cheap so worth a shot I guess. Il keep you posted

[don kalmar union]

If my memory serves me well the 850R was the first Volvo to run the Motronic 4.4 rather than the 4.3 in the earlier cars, they have different internal voltages and cannot be swapped.

But like for like if you have bought a spare ECU for the earlier cars if you put it in your car and it runs it, however roughly, you can flash it with the calibrations that you need, either standard or aftermarket. So certainly try before you buy.

Don.

[MoleT-5R]

Thanks for the replies guys. I have (I assume) an obd 2 port below the radio in a 96 model year car so guess will have to see, got one cheap so worth a shot I guess. Il keep you posted

and does it run???, being obd11 you stand a better chance, but it's not guaranteed.....good luck and keep us posted, it would also be handy to know the ecu no. for further reference

[Bigsi15]

Ok update. Unplugged battery, put in new ecu, connected battery and started fine. All other equipment works fine. Only thing I am getting is periods of uncontrolled boost. I believe stock is around 12 psi but I'm getting spikes up to 1 bar then drops back a bit. Seems to do this from about 3k rpm onwards. Goes really quickly too. The ecu was once tuned but this was reset as per my request to stock r and I see no reason to not believe he did it. Ran fine on t5 ecu although occasionally a bit low on boost. Will have a fiddle tomorrow to check vac lines which are pretty new and loosen wastegate a bit as I think I gave it a turn or so before. Any other ideas?

Thanks guys

[martin_r_smith]

Wasn't the extra horses the R had gained by allowing an overboost to occur? Could be me talking bullocks though.

[claymore]

Wasn't the extra horses the R had gained by allowing an overboost to occur? Could be me talking bullocks though.

that was the T-5R

[MoleT-5R]

could the bcs be on it's last legs...just a thought

[Bigsi15]

Yes I was thinking that possibly too. Or wastegate, seems to restrict the boost at wot but only up to about 2.5-3k rpm then peaks. Seems to be worsening too, earlier it would spike slowly then settle around 0.9-1 bar

[MoleT-5R]

Yes I was thinking that possibly too. Or wastegate, seems to restrict the boost at wot but only up to about 2.5-3k rpm then peaks. Seems to be worsening too, earlier it would spike slowly then settle around 0.9-1 bar

bit of wastegate creep....possible

[Bigsi15]

Can you explain that more for me please? Iv read a bit about that but what symptoms will that give and how can I resolve it? I wonder if I have the actuator a bit tight as I turned it a turn or so on my original setup a while ago. Sorry it's probably a very easy answer!

Thanks all very much once again

[Bigsi15]

So found this in the Garrett site, almost perfectly describes it:
A. Boost creep is a condition of rising boost levels past what the predetermined level has been set at. Boost creep is caused by a fully opened Wastegates not being able to flow enough exhaust to bypass the housing via the Wastegates itself. For example, if your boost is set to 12psi, and you go into full boost, you will see a quick rise to 12 or 13psi, but as the rpm's increase, the boost levels also increase beyond what the boost controller or stock settings were. Boost creep is typically more pronounced at higher rpm's since there is more exhaust flow present for the Wastegates to bypass. Effective methods of avoiding or eliminating boost creep include porting the internal Wastegates opening to allow more airflow out of the turbine, or to use an external Wastegates.

Mole you may have hit it on the head there. Any ideas how to solve this, can you tighten the arm too much so it limits the opening perhaps?

Thanks again

[MoleT-5R]

So found this in the Garrett site, almost perfectly describes it:
A. Boost creep is a condition of rising boost levels past what the predetermined level has been set at. Boost creep is caused by a fully opened Wastegates not being able to flow enough exhaust to bypass the housing via the Wastegates itself. For example, if your boost is set to 12psi, and you go into full boost, you will see a quick rise to 12 or 13psi, but as the rpm's increase, the boost levels also increase beyond what the boost controller or stock settings were. Boost creep is typically more pronounced at higher rpm's since there is more exhaust flow present for the Wastegates to bypass. Effective methods of avoiding or eliminating boost creep include porting the internal Wastegates opening to allow more airflow out of the turbine, or to use an external Wastegates.

Mole you may have hit it on the head there. Any ideas how to solve this, can you tighten the arm too much so it limits the opening perhaps?

Thanks again

over-tightening is not a good idea and most probably will cause your boost spikes, If we've found the issue and
I am correct in how I've heard how this next step should be done, then you should really now wind the actuator back off and then re-set the actuator to standard or desired boost level without the bcs plumped in ( boost gauge required here ), but still connected to the wiring ( else limp/mil mode will trigger ), when desired base boost level is set the bcs can be replumbed, Boost cut could possibly occur if your on a standard ecu ( then slacken the rod a half turn at a time till the problem is cured ).

[MoleT-5R]

So found this in the Garrett site, almost perfectly describes it:
A. Boost creep is a condition of rising boost levels past what the predetermined level has been set at. Boost creep is caused by a fully opened Wastegates not being able to flow enough exhaust to bypass the housing via the Wastegates itself. For example, if your boost is set to 12psi, and you go into full boost, you will see a quick rise to 12 or 13psi, but as the rpm's increase, the boost levels also increase beyond what the boost controller or stock settings were. Boost creep is typically more pronounced at higher rpm's since there is more exhaust flow present for the Wastegates to bypass. Effective methods of avoiding or eliminating boost creep include porting the internal Wastegates opening to allow more airflow out of the turbine, or to use an external Wastegates.

Mole you may have hit it on the head there. Any ideas how to solve this, can you tighten the arm too much so it limits the opening perhaps?

Thanks again

also after reading this post again, aren't we be really talking about wastegate creep, where as boost levels rise the wastegate creeps open earlier than it's predetermined setting thus your boost tails off before it should, this would be common for a failing/old actuator

[Bigsi15]

So I tried Lengthening the waste gate arm today just in case it was unable to push far enough to open enough, turned it about 1 1/2 turns and it's done nothing. I can only assume at this stage the ECU was perhaps not set back to standard properly as leaving everything alone as is and using my stock ECU in runs absolutely fine. I'll send it back to the chap for another go and keep you updated! Thanks for the help so far

[claymore]

You could have gained your "slight performance increase" by simply fitting a MBC, I don't know why you would bother faffing about with swapping to a 850R ecu, why not fit a HLM or Rica ecu?

[Bigsi15]

You're absolutely right, at the moment though I am looking for a stock replacement to avoid major insurance issues. The plan (very slow work in progress!) is another engine build with stronger rods and a number of supporting modes including a good tune but that is still quite a way off so this would be a stopgap and out of interest as well really

[Bigsi15]

There are obviously a lot of far more intelligent people on here than me who know a lot more about maps :-) I was wondering if I could rack your brains! I have read a lot about how too much boost too lowdown with an incorrect map can do a lot of damage to a stock engine mainly the rods, but I don't seem to be able to find any more detail on what too much boost actually is. This ECU in its current state seems to steadily build to about 0.4 bar from 2000-2500 rpm reaching about 0.8 bar by 3000 rpm which I believe is about stock target for an r, it will then however spike quite suddenly up to about 1 to 1.1 bar within 3-3.5k rpmthen drop back a bit. This is about 15 PSI isn't it which I believe is when the stock ECU will try and cut things back for safety. Is this a dangerous tune for a stock engine and turbo? Thanks guys sorry for all the questions!

[claymore]

you're not going to bend rods with a 15g, I'm using an 18T with a HLM Map and a bleed valve at 22psi, and my rods are fine, as long as you don't hit full boost under 3500rpm you will be fine

[Bigsi15]

Thanks claymore. That's a decent setup if your on stock internals :) can a bad tune do any harm if a 15g isn't in itself capable of? Iv heard too sudden boost build up is bad or if not tuned right can get very hot or run lean?

[claymore]

just get a hlm, rica or shem ecu and be done with it (much safer than playing around with a 850R ecu for very little gain) you're over thinking things, Adrian has a 15G and a basic tuned ecu and is managing low 14's on the quarter mile

[claymore]

look, no bent rods.

https://www.youtube.com/watch?v=VgB_6WFrHlM

[Bigsi15]

Yeah think your right, il just wait till the final build is done then get on to Shem or Tim and let them do the hard bit! Lol! Thanks for your help buddy :)

[MoleT-5R]

Yeah think your right, il just wait till the final build is done then get on to Shem or Tim and let them do the hard bit! Lol! Thanks for your help buddy :)

Where you racing a Gul to Cosford in that clip......lol......Seriously though I run high boost on standard rods just and make use of the higher rev range so when you change up you don't drop into 3000-3500rpm danger zone, mines been boosted and hammered daily for over 9 years and going stronger and stronger ( it will go bang sometime soon , but it is a 300,000 miler with a 200,000+ engine and I drag the arse off it chasing the 13's)...:):):):)

[Bigsi15]

Haha thanks mole. What's your setup? My other worry is that the ecu has not been set up for my car so not sure on timing and air fuel ratios etc which makes me cautious!