How different are these engines?
- Thread starter Perrin21
- Start date
Really quite different; you're talking about 15 years difference in the age of them for a start.
- The EVO will have a 4G63 MIVEC engine; so that's variable valve timing which the SR20DET doesn't have (the closest alternative is the SR20VET from a JDM X-Trail)
- I'm pretty sure Mitsubishi use a twin-scroll turbocharger; ours is only a single port (although there is some debate about how much use twin-scroll is on a 4 cylinder car because the pulse won't be very pronounced)
- I'm told that the Mitsubishi conrods won't take nearly the punishment that ours will (although that's just hearsay)
If they were both 300 bhp and in the same car there wouldnt be a difference in actual performance :lol:
Differences would show between the two engines, as said already one design is 15 years older than the other and we would hope that over several different versions the Mitsubishi engine might produce 300 BHP more efficiently then the age old SR20DET.
They might both produce 300 BHP but due to basic things like engine design materials used, crank throw, con rod length, piston cylinder bore and depth, oiling system etc. etc. they will both deliver the power in different ways throughout there given power band.
They might both produce 300 BHP but due to basic things like engine design materials used, crank throw, con rod length, piston cylinder bore and depth, oiling system etc. etc. they will both deliver the power in different ways throughout there given power band.
Makaveli_se7en
Member
Key differences in engine architecture that i can think of (other than those stated) include:
4g63 - belt driven cam (quiet), sr20det - chain (long service intervals)
4g63 - cast iron block (good for big power without mods, but heavy), sr20det - Aluminium block (lighter but needs steel liners for big power)
4g63 - under square (85mm bore, 88mm stroke), sr20det - square (86mm x 86mm)
I'm deffinately in the SR20 camp. Its taken Mitsubishi two decades to catch on and switch to an aluminium block in the Evo X (4B11). Same with ford the duratec looks suspiciously like an SR20 in alot of ways.
4g63 - belt driven cam (quiet), sr20det - chain (long service intervals)
4g63 - cast iron block (good for big power without mods, but heavy), sr20det - Aluminium block (lighter but needs steel liners for big power)
4g63 - under square (85mm bore, 88mm stroke), sr20det - square (86mm x 86mm)
I'm deffinately in the SR20 camp. Its taken Mitsubishi two decades to catch on and switch to an aluminium block in the Evo X (4B11). Same with ford the duratec looks suspiciously like an SR20 in alot of ways.
Makaveli_se7en
Member
The MIVEC system works on just adjusting the timing by essentially rotating the cam much like the Rover VVC system. The VET system has separate cam lobes like VTEC and is a far superior system.
With engines of teh same capacity lag will have more to do with the turbo strapped to the engine and the mapping, but the evo will probabley be slightly better stock for stock as it has a higher CR (8.8:1 vs 8.3:1).
If you stuck say a gt30 on both engines I don't think there would be a great amount of difference in response and the power produced. Both engines have their good and bad points, the rods are a lot better on the sr20 and I don't think the standard pistons are as bad as people have made out over the years ;-)
red reading
Active Member
standard pistons as you say mark were actually pretty good, the problem with all these cars is the mappers that didn't know what they were doing.
What was wrong with the original maps? Say compared to modern mapping
vpulsar
Well-Known Member
My standard pistons took 399 bhp for over two years before the ring lands went on one of them, Which was quite handy really because we caught the crank bearings just intime to stop the crank getting damaged.
I don't think you can say one engine is better than the other, They both do the same job but one is a lot newer design so as others have said will be more efficiant in what it does. The SR20 is a very good engine if looked after properly. The only reason it has a bad reputation in some eyes for weak pistons is bad mapping or some ned wacking up the boost with out regard for fueling, Same goes for the gearbox really another undeserved bad reputation bought on by some young scrots thrashing the life out of the poor thing.
John
vpulsar
Well-Known Member
The Pulsars run very rich so their is plenty of scope for a good mapper to not only save fuel but to get a lot nicer car to drive.
John
Makaveli_se7en
Member
Out of interest does any one know how much the 4g63 developed over its life time as the original (evo 1 engine) is essentially the same age as the SR20?
My car has been reasonably close to that sort of power now on the original 134,000 mile engine since October and (touch wood) all is still well. Don't know the exact power as i never bother with dyno figures. Its done god knows how many track days, sprints, hillclimbs, airfield days in the 8 1/2 years i've owned it too which just goes to show what a good engine it is when looked after properly ;-)
vpulsar
Well-Known Member
It's all about good maintenance and efficient heat control, If you achieve these two things then their is no reason you good old SR20 wont give you plenty of happy miles of trouble free motoring, If I where you Mark the only thing I'd be worried about is the condition of the crank bearings.
John
red reading
Active Member
Same here,i had a chat with the owner of vandervell bearings a few years ago and appaentley the standard aluminium over steel nissan bearings are not very good, they can work harden and then fail and also they will be prone to deformation without the ability to return to original shape (due to aluminiums nature from heat cycles of work hardening) which means they will fail.
He said that the ACL material is bloody close to what he would spec for there use, but that the calico coating was a load of b0ll0cks.
Forgot to mention cooling, i've got a uk car so the radiator is twice as thick as a standard one. Add to that the 19 row oil cooler and thats probably been a major point in making the engine last so long!