Fitting new engine to murena and som e questions

[Oskar]

Im fitting an xu9j4 (peugeot mi16) and have some questions about inlet manifold and exhaust manifold.

Ive shortened the inlet so it can be fitted.

Im thinking of getting an exhaustdistance for the manifold so it can be fitted without cutting the boot.

also how further back must the engine sit? How imported is it for the driveshafts to be alligned?

[matramurena]

Maybe you should contavt Carjoy in the Netherlands. They just finished a MI16 conversion and did it the way it should be done!. They didn't cut any of the original parts, but made a special left-rear trailing-arm so that the engine fits without having to cut in the chassis of the Murena. Also they placed a fuel-tank in the front so they didn't have to cut in the inlet-manifold. Thus keeping the air-flow as good as originally planned by the PSA-engineers....

[roy4matra]

also how further back must the engine sit? How imported is it for the driveshafts to be alligned?

Drive shaft alignment is very important, particularly if you want them and the drive system to be reliable.  The manufacturer spends a lot of time getting this right when the car is designed, and this is just one of the problems an amateur is faced with, when changing any car to a different powertrain.

Roy

[Oskar]

Seems that the left trailing arm is the main problem. Gearbox has to sit as high up as possible to free the suspension travel as much as possible.
to be continue...

[uberprutser]

Good to know that I'm not the only one doing an engine conversion on this forum
Michaltalbot most be going mad right about now 

Assuming you have a 1.6 chassis can't you hack out the right engine mount so you can move the engine further to the right?
You could also consider modifying your trailing arm but I would not do that if you have the original 1.6 arms they seem a bit weak to weld on.
Also using 2.2 trailing arms would give you a bit more space since the 2.2 had a wider wheelbase.

I would be reluctant to modify the original intake manifold. You will loose torque when shortening them. Torque = Good.

I would not worry about the drive-shaft being a bit misaligned. It isn't even possible to align them 100% because of the wheel camber. Trowing some camping equipment in the boot will misalign the drive-shaft and people take long camping trips... Did you ever hear any drive-shaft horror stories?

Try getting equal length drive-shafts. These cars have a lot of wheel travel and extreme angles will put extra load on the shortest drive-shaft.
I would also try to mount the engine horizontal and as low as possible. 

And most of all, don't take my advice to serious because I'm the biggest amateur in the northern hemisphere. Do whatever you want and have fun doing it

Goodluck with your project.
 

[Oskar]

thanks for your input

The engine is rather modified, Shortened inlet as you se, forged pistons and lowerd compression.
Will be later fitted with a small turbo gt17.  max power output will be 200hp. Clutch and turbo has this limits.

Ill allign the engine as good as possible. The right hand enginemount will be cutted 20mm so there will be some more space.

I´ll fit coilovers and maybe some bumpstops to ensure the gearbox goes free from trailingarm when heavy load is applyed.

[michaltalbot]

Michaltalbot most be going mad right about now 

No, I just resigned on this, but I still think, that tuners like these, have to try their skills on VW Golf or BMW 3er and not on very rare and unique sport car, which was made by really clever technicians, who have to vomit when seeing this 

I would be reluctant to modify the original intake manifold. You will loose torque when shortening them. Torque = Good.

That's one of the good points - as longer the intake manifold is, it's even better because air have longer way to kalm down.

As You wrote - everybody could do, what he wants with his car, but without technical knowlege, the result will only be a miserable... And everybody could say what he thinks about it 
At least, I would like to see the graph of this Mi16 producing 200 bhp 

[Oskar]

if you have seen the powercurve of mi16 you would know theres a dip around 3500rpm couse of the manifold and inlet cam.  The high reving engine makes it power around 7000rpm where it leans out on fuel.
shorter inlet, faster air travel, makes it more suitable.  I really like this engine and the sound 

Ive been working with this engine family for a long time with my 205 gti. But our mot put an end of it...

[michaltalbot]

The high reving engine makes it power around 7000rpm where it leans out on fuel.
shorter inlet, faster air travel, makes it more suitable.

I know I am the black sheep at this forum   , but I only try to avoid You from needless mistakes, because internet is full of informations, but also full of bullshits...

Some facts:
1) high rews are depended on the weight of piston + connecting rod, for +7000 rpm You have to use forged pistons, cos they are much lighter. This relates
to the speed which piston have to change every way up and down, much rpm = higher speed, heavier piston = bigger forces on whole group (piston, rod,
crankshaft, bearings). That's why Matra V12 3,0 could go to 10500 rpm - pistons were small and light.
2) shorter inlet, faster air travel, better running - this is wrong. In fact, You don't need a bigger speed of air to reach higher efficiency of Your engine ( = more power), because there
is still the same amount of it and of gas You're putting inside, You need to get as much of fuel (gas + oxygen) as possible into the cylinder. Turbo or
Compressor is not there for fastering the air, but for making bigger pressure = to give bigger amount of air into the cylinder at the same time than at
normal engine, because than there also could be injected more gas. But still, constructers tried to calm down the air as possible, look how long is
 the inlet in P505 Turbo, but they are limited with space, weight and material spending. When You'll make the inlet too fast, it will bring a lot of swirls
inside the cylinder and it will complicate the filling up of the cylinder. It's the same with polishing the inlet from inside - the reason is not in speeding the air,
but in eliminating of swirls. Just make a little test - take a big syrette and try to take water from glass of water (that's the same when air is calmed down)
and than try to take water from old rusted water pipe, even if You'll put it against the stream, You'l get a lot of bubbles and foam.
3) next thing is cooling of the engine, if I understood well, it has the exhaust in front and inlet in rear side of the engine room. In Murena, the cooling air is
going from bottom of the car, than up passing the air intake, and back down arround the exhaust. Some amount of the air goes by the lower part of the
engine and is cooling the oil in crank box. But what happens when You'll heat up the air before it will go arround the rest of the engine? Maybe nothing,
but You have to know this before realising project like this. Otherwise it's the same like guys who put spoilers on their cars, but have no idea what it brings - in
fact 90% of them are only doing worse for their aerodynamics. The rear spoiler on Murena S makes 10kg at 190km/h, don't think that 90% of tuners have
awareness of functionality of their spoilers...

Facts like these are very important if You really want to reach something better than original and not only a dangerous, crappy bastard  
So at least, I preffer to cutting out the boot and using the 2,2 Turbo with direct exhaust, good placed intercooler and clean made intake

[Oskar]

im sorry i only see this car as a funny part i can stick whatever in it ;-)
it is in fact in really poor condition and im just gonna make it a fake heart so i can punnish it on the roads.

you love matra to much for your own good ;-)