More oomph for my V6

[paraic]

HI all

I really love my 88 STX V6 but at times I feel a little lost when it comes to raw power. I see standard American cars outgun me and our family car a Buick LeSabre 04 easily takes me above 30mph (though it does have a nice engine anyway so I don't feel so bad).

The engine is in good shape and did well in the leak down test so I don't mind stressing it a bit. Its originally a Californian car with only one previous owner so it has a CAT which is one area I would look into for performance improvement. I am originally from Ireland where I had a really nice 89 V6 which really could move but it had the higher bhp European engine and no CAT. So I always feel like my 505 is underpowered comapred to the European model.

So I would love to hear any suggestions - stuff like fans, electrical and bolt on stuff that could help. To be honest an extra 10-20% is really all I need to make me feel like the car can accelerate when I need it.

Thanks

Paraic

P.S, I would love to get one of the 89 model trunk spoilers if anyone has one or knows if they can still be gotten somewhere.

[anj]

HI all

I really love my 88 STX V6 but at times I feel a little lost when it comes to raw power. I see standard American cars outgun me and our family car a Buick LeSabre 84 easily takes me above 30mph (though it does have a nice engine anyway so I don't feel so bad).

The engine is in good shape and did well in the leak down test so I don't mind stressing it a bit. Its originally a Californian car with only one previous owner so it has a CAT which is one area I would look into for performance improvement. I am originally from Ireland where I had a really nice 89 V6 which really could move but it had the higher bhp European engine and no CAT. So I always feel like my 505 is underpowered comapred to the European model.

So I would love to hear any suggestions - stuff like fans, electrical and bolt on stuff that could help. To be honest an extra 10-20% is really all I need to make me feel like the car can accelerate when I need it.

Thanks

Paraic

P.S, I would love to get one of the 89 model trunk spoilers if anyone has one or knows if they can still be gotten somewhere.

Hi Paraic

On my list to get the car to run at its peak is to change the exhaust manifolds to the the Eagle Premier ones. I had Renault headers given to me by Rabin but they were going to require some modification to work. I have purchased the Eagle ones from Ebay for 100.00 and gaskets from Special T auto. They are quite different and hopefully a direct bolt in. This may be the most bang for the buck but I will let you know.

Arun

[andrethx]

special t auto is a great resource, john (hervey) is the man! it's a parts site for deloreans, but many of the parts that john sells work on our cars as well. have bought a few fuel system parts from there...

andré

[Bean]

It's been mentioned before - but never tried on sourcing a euro spec ECU and plugging it into a USDM car. I'm not sure what all the mechanical differences are between the two engines, but I would bet a fair bit is in the ECU tuning.

Aside from the basics of improving intake and exhaust - the next steps involve increasing compression and changing cams. Forced induction is another alternative - but it definitely gets pricey very quickly.

I'm curious about the comparison to US cars - I find that US cars are geared and tuned for low speed response, and generally fall short at highway speed. So while the V6 will be beaten off the line, but they come into their own at highway speed.

Rabin

[Bean]

On my list to get the car to run at its peak is to change the exhaust manifolds to the the Eagle Premier ones. I had Renault headers given to me by Rabin but they were going to require some modification to work. I have purchased the Eagle ones from Ebay for 100.00 and gaskets from Special T auto. They are quite different and hopefully a direct bolt in. This may be the most bang for the buck but I will let you know.

Arun - you'll have to post pics of the difference. I've only seen the Eagle once briefly - but I thought they were either the same or very similar to the Renault T30 ones.

Rabin

[JunktionFET]

The 170hp version of the V6 had higher compression than our 145hp version (10:1 vs 9.5:1), and of course the ECUs were different. Still, I bet the European ECUs would yield at least some bump in power for our cars as I'm sure it's more aggressively tuned.

It is a shame the timing can't be adjusted.

A good tune up might help if the car hasn't had one in a while. Every single ZN3J I came across when I was a tech needed a valve adjustment BAD. Clean the throttle body, replace air and fuel filters, perhaps run SeaFoam or similar product to clean carbon deposits. Retorque the knock sensor to ensure it isn't picking up "false" knocking and retarding timing for no reason.

I have no idea what impact this might have on the engine's life, but you could remove the balance shaft assembly from the cylinder head since it sucks a small amount of power and adds some inertia to the engine.

[Bean]

I've read that you can mill the head a bit to increase compression as well, but I think sourcing a euro ECU would definitely help as it's likely fueled and timed much more aggressively.

If you can justify the costs - I've always felt a supercharger would be the way to go on a PRV. Rotrex makes a really sweet SC that would suit the engine quite nicely...

Bang for the buck would be the Eagle exhaust manifolds, the stock log manifold looks absolutely terrible for flow. I've also read that the PRV really benefits with upgraded spark - so fitting an MSD or similar system might help it out as well. The 505 Turbo gets a very noticeable improvement running an MSD 6AL.

Rabin

[paraic]

I've read that you can mill the head a bit to increase compression as well, but I think sourcing a euro ECU would definitely help as it's likely fueled and timed much more aggressively.

If you can justify the costs - I've always felt a supercharger would be the way to go on a PRV. Rotrex makes a really sweet SC that would suit the engine quite nicely...

Bang for the buck would be the Eagle exhaust manifolds, the stock log manifold looks absolutely terrible for flow. I've also read that the PRV really benefits with upgraded spark - so fitting an MSD or similar system might help it out as well. The 505 Turbo gets a very noticeable improvement running an MSD 6AL.

Rabin

So I decided to go the ECU route and Ikenna, who has been there and done that, has located both Euro spec ECUs for me. We are getting it shipped from Nigeria and its quite affordable all round - less than $350 incl S&H. it remains to be seen what improvement I will get - I will report out when I get it installed.

The Eagle Premier exhaust manifolds are a very enticing option as well - I see them on Ebay for less than $100. What kind of labor are we talking about (# of hours) as I won't be able to do this myself and will be asking Dave in Eurocar to do the business.

Finally, an unrelated question, from the photo at the beginning of this thread, you can see the car has a maroon color. I looked in the engine bay for the code for that and its nowhere to be seen. Dave in Eurocar checked as well. Do any of you know what that maroon color code or name might be? I do need to get the hood and trunk resprayed to deal with the clearcoat problem.

Thanks

Paraic

P.S. Even without that extra oomph, I do still love driving my V6 - its a blast and even as it leans heavily around corners, its actually a great cornering car. The 505 is just about the best thing that came out of the 80's IMHO

[Bean]

I'm very curious to hear how the euro ECU works out! I would bet the chip in it could be copied and installed in North American ECU's...

Exhaust - it's tight, but it should be doable. It will be hard to guess how much time as it all depends on how easy it is to remove the manifold bolts, and what if any stud replacements have to be done. It can vary from 1-2 hours to install - to being a whole day nightmare if the studs break. (Previous experience on other cars)

If you do attempt it - I would recommend soaking it down with penetrating oil for days before taking it to Dave. Not sure if Dave has muffler / tube bending equipment / welds up mandrel - but the outlet for the Eagle manifolds are different so you'll either need new downpipes, or the stock ones modified to fit.

Paint matching - your best bet is to find a shop that uses one of the latest optical spectrum analyzers that read existing paint colour and formulate custom mixes. This is the best way to match existing paint and will account for any variances on the car. When mine was done they took paint readings from the door jams and it's a perfect match. They compared the custom mix to the factory code recipe and it was slightly different.

Rabin

[andrethx]

for an 87, a maroon car will be rouge classic (classic red), color code EJQ/AJQ or 1503. you can confirm this, on 505s the color code is usually painted on the driver's side shock tower under the hood (see my build thread for an example). rabin's right, though, the color will have no doubt faded over the years so unless you are doing a complete respray, you should look at some sort of color-matching.

i have bought several items through ikenna, he is scrupulously honest and exceedingly generous with his time -- i consider him a good friend. you are in excellent hands....

andré

[anj]

So I decided to go the ECU route and Ikenna, who has been there and done that, has located both Euro spec ECUs for me. We are getting it shipped from Nigeria and its quite affordable all round - less than $350 incl S&H. it remains to be seen what improvement I will get - I will report out when I get it installed.

The Eagle Premier exhaust manifolds are a very enticing option as well - I see them on Ebay for less than $100. What kind of labor are we talking about (# of hours) as I won't be able to do this myself and will be asking Dave in Eurocar to do the business.

Finally, an unrelated question, from the photo at the beginning of this thread, you can see the car has a maroon color. I looked in the engine bay for the code for that and its nowhere to be seen. Dave in Eurocar checked as well. Do any of you know what that maroon color code or name might be? I do need to get the hood and trunk resprayed to deal with the clearcoat problem.

Thanks

Paraic

P.S. Even without that extra oomph, I do still love driving my V6 - its a blast and even as it leans heavily around corners, its actually a great cornering car. The 505 is just about the best thing that came out of the 80's IMHO

Hi Paraic

It will be interesting to see if both the modifications independently make a significant change and if it does of course I would be interested in the ECU upgrade. The cost is very similar the eagle headers with coating should run about 400.00. I wish we could quantify both the results with dyno rather then subjective. I may invest in doing a dyno run to get a baseline after I adjust the valves. I am also very interested in the cumulative gains from both mods.

Arun

[bryancohnracing]

I would highly recommend dynoing your cars BEFORE and AFTER work such as this. It is the only way you will know you've made improvements.

My experience is with Dynojet brand chassis dyno's, tuning (or trying to tune) the 505 and Miata race cars. In both cases it was worth the time, effort and expense.

The guy I trust is 2 hours away in Topeka KS....

Don't forget that the quoted horsepower in all documentation is SAE at the flywheel, not the rear wheels. Using my cars as examples, the Miata makes 118 hp stock at the flywheel. In tuned, race ready trim it made 132hp at the rear wheels. If you figure 10-15% loss through the drive train (industry accepted percentages), using 10% that 118 hp is really 106.8 hp at the wheels stock. Hence 132 hp at the wheels is a HUGE improvement. Same for the 505, it put out 167 hp at the wheels, stock is 150 at the flywheel. That's 135 hp at the wheels in stock form....so 167 hp at the wheels is a nice bump!

As you can see the math doesn't lie. So find a reputable dyno, pay for 3 runs to establish a base line, which is pretty much the industry wide standard, make the mods and then go back and run it again. You'll have real world numbers!

Dynojet has a cool dyno locator on their website. Its also the only approved dyno for most racing organizations that use dyno certification for various racing classes. NASA, Grand Am, AMA are but a few that use Dynojet.

[Ikenna]

I got a missing section of ZN3J workshop manual from Paul today. While going through it, I gathered that not all Euro Spec 505 V6 had 170 hp ECUs. It went further stating that all 505 V6 with factory Catalytic Converter had 145 hp ECUs, hence, the North American 505 V6 spec & some Euro spec with Cat. Converter. But that the Euro spec 505 V6 without factory Catalytic Converter all had the 170 hp ECUs. Which I believe is why the 170 hp ECUs are rare to find.

Paraic,

I have shipped the 2 Euro spec 170 hp ECUs (ignition & Injection) to you 2 days ago (Monday). I believe you should get them in two weeks time or less.

Ikenna.

[paraic]

I got a missing section of ZN3J workshop manual from Paul today. While going through it, I gathered that not all Euro Spec 505 V6 had 170 hp ECUs. It went further stating that all 505 V6 with factory Catalytic Converter had 145 hp ECUs, hence, the North American 505 V6 spec & some Euro spec with Cat. Converter. But that the Euro spec 505 V6 without factory Catalytic Converter all had the 170 hp ECUs. Which I believe is why the 170 hp ECUs are rare to find.

Paraic,

I have shipped the 2 Euro spec 170 hp ECUs (ignition & Injection) to you 2 days ago (Monday). I believe you should get them in two weeks time or less.

Ikenna.

I have to re-iterate Andre's comment earlier that dealing with Ikenna is a delight and he is indeed generous with his time and his knowledge. I had to resend the WU money order 3 times due to incompetence in the store I got it from - they got his name wrong twice even though it was 100% legible on the form. So that meant 3 trips to the bank to collect the money. I don't know about you guys but would have annoyed me somewhat, especially since the whole thing was a favor from start to finish. And yet Ikenna took it in his stride and never complained. And then when he was shipped a bad ECU after testing it in his own car, he simply shipped his own spare and then dealt with the dealer to return the bad one.

Outstanding!

My thanks to you Ikenna and if you are up to it I would love to do more business with you or do some favors for you from my end here in the US. Dave from Eurocar was more than happy to answer some questions for you if you want to pursue that. He has all the Peugeot knowledge you would ever need and the tools and reference material to go with it.

Paraic

[pushgo]

I may very well contacting Ikenna very soon with regards to some v6 parts.

[paraic]

Speaking of ECUs, has anyone has any experience with MegaSquirt and the PRV?

I see some DeLoreans have used it but didn't see any Volvos or 505s.

http://www.megasquirt.info/

It does sound like a lot of work and serious understanding of how your current ECU works. The claims and reports are pretty substantial. Apart from performance, there is better mpg and smoother running.

[Bean]

I've done hours and hours of research on this and the overwhelming consensus is that if are not doing forced induction or major engine mods, it takes a LOT of effort just to get as good as the stock EFI system. If you're simply wanting to change the ECU the gains seen will be miniscule if any - and more often it's worse.

Cams, compression, boost etc etc and that is where a stand alone system is valuable as it allows you to tune out of the ranges the stock EFI is set up for.

Rabin

[paraic]

Well the ECUs arrived today. Thanks Ikenna!

I will stop by Eurocar tomorrow and get them in and see how it runs initially.

I will report out as soon as I have news.

Its an interesting experiment for sure.

Paraic

[andrethx]

please report! it will be interesting to see what happens.

btw -- not sure if your v6 is a lot different, but on my xn6, the ecu is very easy to replace, it's just two screws and a large amphenol-style connector. it's behind the glovebox, which itself is held on by two screws along the bottom...replacing the ecu literally takes 2 minutes...

andré

[paraic]

Well the ECUs arrived today. Thanks Ikenna!

I will stop by Eurocar tomorrow and get them in and see how it runs initially.

I will report out as soon as I have news.

Its an interesting experiment for sure.

Paraic

Got the two ECUs installed finally. Wow what a difference!

The car's low rev acceleration is way better and the overall smoothness is substantially better.

I did this in two stages actually. I put the ignition ECU in first and since I have problems getting the screws out for the injection one, I left it for another day. I noticed an immediate improvement with the new ignition ECU, paired with the old Injection ECU. Definite low rev acceleration improvement and a nicer smoother overall acceleration. I was pleased enough with that by itself, until I put the injection ECU and I got another increase in ooomph.

However there is so far one downside - the introduction of the injection ECU, while giving more pep has made the car run a little rough - just enough to notice. I don't know if this will even out over time as some ECUs do, but its a small concern. I imagine my gas mileage is going to drop also with the extra power I'm getting.

Ikenna asked about emissions - I did not notice any changes in emissions - any black smoke or other unwelcome emissions. I will keep the old ECUs in case the idle issue is unacceptable. And also in case I need them to pass the emissions test which are not so strict in Europe.

So I would highly recommend the ignition ECU - there were no side effects. And if I can sort out the rough idle in the injection ECU, I would also recommend that.

Paraic

[Ikenna]

Am glad to hear that your ECUs arrived safely, but am not happy with what the Injection ECU is doing. Does it rev smoothly, but only run rough when idling, with the injection ECU? The rough idling, I think, may mean that the air/fuel mixture is not proper(not sure). Does the injection ECU cause hard starting since you plugged it in?

Well, I could at least say that ZN3J injection ECU also re-learn like other ECUs. I could remember sometimes when working on my ZN3J harness, the car would suddenly start running as if the issues have gone. But after a while, it will go back to those issues, indicating that the harness still have wrong connections somewhere, which I have identified the places, with the complete ZN3J electrical diagram Paul scanned & forwarded to me. I just hope its trying to adjust to the new whatever. But I dont just know. I feel sad about it. But all hope is not yet lost, like you said. Just continue with the observation. Meanwhile, I believe others might have some inputs or suggestions to make, since I have no clue what could be wrong.

Ikenna.

[Ikenna]

It just occured to me that those 2 ECUs (Bosch 0 280 001 507 & Bosch 0 227 400 121) were meant to run with ZN3J without Catalytic converter, as stated in the ZN3J workshop manual. Does your STX have the Cat Converter? Could that be the reason why the Injection ECU is misbehaving? Even the manual also stated that the spark plugs for ZN3J with catalytic converter is HR6 DC, while the ZN3J without Cat converter is HR5 DC. Could it also mean that the spark plugs for Cat converter wont work properly with the ECUs for non Car converter, that you have?

Please, everyone, what do you think?

Ikenna

[Ikenna]

Reading into the manual, I gathered also that those 2 aggressive ECUs are not meant to run with ZN3J with Oxygen sensors. Then it struck me. When i purchased that Injection ECU, it came with the wiring connector/socket plugged onto it (just like the ignition ECU you received that also had it socket on it). So, there was a day I opened the cover of the connector the ECU came with & I saw that the wire no. 20 & it pin was not included in the connector. Check your ZN3J diagram, wire 20 is the o2 sensor signal wire to ECU. Meaning that the 505 V6 that the seller removed that ECU from & sold to me had no o2 sensor as factory. So, that Injection ECU was not running with oxygen sensor from the car it originally came from. Am holding & looking at that ECU connector now. There is no provision for o2 sensor on that socket. So, aside what the manual stated, I have confirmed it with my only very eyes right now as am writing this.

If I were you, I would disconnect the o2 sensor, especially the signal wire, to see if there will be any improvement or elimination of the rough idling. Whether those ECUs can still work with o2 sensor & Catalytic Converter, even though the manual stated it shouldnt, it wont hurt to try. Start with disconnecting the o2 sensor harness from the sensor. You never know, it may fix the problem without removing the catalytic converter.

If I think of anything else, I will let you know.

Ikenna.

[paraic]

Very interesting Ikenna.

Dave in Eurocar is looking up his info and can tell if my car has an O2 sensor. It most likley does.

We will see if disconnecting the sensor is a good idea - is it an easy task?

Paraic

[Ikenna]

Yes, it is an easy task. The o2 sesnsor is screwed into the catalytic converter, I believe. Though, some ZN3J o2 are installed on exhasut manifold. Anyway, the catalytic converter is under the car, directly under the gearbox. The sensor should have 2 sockets, if it still have factory o2 sensor. Separate the 2 sockets from each other, temporary & test by starting the car to see if any improvement. If no improvement, you can then plug back the sockets.

Ikenna