My Quadra

[Andyquadra]

So far this week I'v finished off building a 21t engine and dropped it off to the dyno.... not my engine
Watch this space
Andy

Well, its built and dyno'd now! I guess the power's ok LOL
Engine spec is
Renault 4 cylinder 1995cc J7R 720 aluminium block with under piston oil jets & modified to accept turbo oil return feed.
Standard crank lightened, balanced & knife edged.
Standard con rods balanced. (Serdi)
Super Ductile liners (Westwood)
Forged pistons, 8.1 compression (Wossner)
Renault 21 Turbo cylinder head, bigger 46.6mm inlet valves, uprated dual valve springs, dural caps, (Ferry Developments)
Camshaft 268? duration (Cat Cams)
Vernier camshaft pulley (Cat Cams)
Inlet manifold (21 Turbo)
55mm throttle body (Renault 21/25 TXi)
Plenum (Renault 21/25 TXi)
Injectors 660cc (Siemens)
3 Bar MAP Sensor (Ford)
Turbo (Garrett GT2860RS dual ball bearing)
Double piston dump valve with 25mm neck (Collins)
3 way boost control valve (Motec)
36-1 crank timing trigger wheel & sensor (Motec/Marelli)
Ecu (Motec M4)
Engine loom (DC Electronics)
Stainless steel exhaust manifold (FBI moteurs)
3? stainless steel exhaust (APT)
3? stainless steel silencer (Borla)
Steel billet flywheel (TTV Racing Components)
200mm clutch pressure plate & twin friction disc (Sachs Racing rated @ 480 ft/lbs))

 

[la21t]

Works well dont it?

 

[shep]

Works well dont it?

:tongue: yeah,im liking that well done m8.

 

[DaveL485]

That thing is gonna get a wiggle on.

Now get yours in there!!!

 

[am21t]

I like that a lot,
well done Andy,

:nod::clap2::clap2::clap2:

be nice to see the car finally on the road & running sweet,

 

[Andyquadra]

I like that a lot,
well done Andy,

:nod::clap2::clap2::clap2:

be nice to see the car finally on the road & running sweet,

Thank you, but its not my engine! I just built it

 

[am21t]

Thank you, but its not my engine! I just built it

Oh silly me,
thought it was going in ur quaddie,

nice anyway,who ever owns that will be a very happy person,

 

[Larsson7]

How much did the engine cost to build then?

 

[Andyquadra]

How much did the engine cost to build then?

That and a bit

---------- Post added at 08:11 PM ---------- Previous post was at 07:13 PM ----------

I must add that this engine was mapped on a dyno and not a rolling road so the power plot figures are at the fly wheel. Having said that the engine's going a 750kg rear wheel car, so its going to shift along quite well!

Andy

 

[Tony]

Nice spec Andy. Is yours going to be near that? Or better?

 

[Andyquadra]

Nice spec Andy. Is yours going to be near that? Or better?

I have no idea Tony, I'v got a GT2871R turbo, same inlet valves but bigger exhaust aswell, the heads been flowed more, the piper 276 regrind cam and its got slightly higher compression. Only a dyno session will tell

Andy

 

[-Jo-]

Nice one Andy. Do you have a datalog from the map ? Why its got that dip at 3500 ? Its about the same powerband ive got with the diff that the mine is a bit later because off the bigger turbo.

 

[MakeEverything]

Well done Andy. So i am stalking the right person for the right information then!??! :shocked::whoo:
The engine looks awesome as well.

 

[Lee_R21Turbo]

Nice one Andy. Do you have a datalog from the map ? Why its got that dip at 3500 ? Its about the same powerband ive got with the diff that the mine is a bit later because off the bigger turbo.

Look at the boost Jo, its not really a dip, its a spike before hand due to the 24psi, then it drops back to 21psi. I reckon if there hadnt been a spike that line would be smoother.

 

[-Jo-]

didnt see the boost figures, my bad. Andy, I dont wanna be an ars but that power is very close to the GT28RS max limits.

 

[B.roadbandit]

Just wondering, should,nt the motec control the boost to prevent spiking?

 

[MakeEverything]

Just wondering, should,nt the motec control the boost to prevent spiking?

Motec wont control the boost, only the fuel and ignition advance / retard. What the car effectively has is two power bands, but with some more tuning that flat spot could probably be taken out, though with the cams, that might prove harder than it sounds i should think.

All IMO of course, considering my limited knowledge of Turbo's and renault engines!!! :nerd:

 

[Lee_R21Turbo]

Nothing wrong with a boost spike provding that theres adequate fuelling there for it - gives it better mid range capabilities.

 

[B.roadbandit]

So with a programable controler u could get it to spike at certain rpm's to fill in the low spots on the torque/power curve to give the engine a more linier feel then?

 

[MakeEverything]

Im working with Megasquirt so its a different system, however the philosophy is still the same. By adjusting the VE table, injector opening times and the ignition map, you should be able to adjust the power curve to a point. Optimal power is achieved by reaching Stoich consistently throughout the power curve, however this can be quite tricky on high power applications as a result of large injectors, increased boost pressure and other "Variables" - each engine is different.

Generally, we tend to go richer than stoich, to avoid pinking, knock and in extreme cases, detonation and it is only at the desired power band that we manage to reach Stoichiometric values in combustion. It would be very interesting (in a nerdy way) to see what the Lambda readings were at the various plots in the map. I suspect that the dip in the power band is as a result of leaning our slightly though it could also be a characteristic of the cam.