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Location:
Melbourne, Victoria
Registered:
December 2004
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Celica engines...
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Mon, 20 December 2004 15:39
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Hi,
Just wondering first off...which would be a better pick for an engine? the 3SFE or 5SFE...like...Coz I've got a 3SFE in my ST184...and I'm just wondering if I should be worried about having a 3S in my car...? Like...yeah...I guess...in terms of tunability and stuff...he he...and I've heard from some places that Turbo'ing a naturally Aspirated motor might be good for the car...like...at first I was put off by stuff on this forum about modifying my engine...and I was thinking of just waiting a few years...get a few years under my belt and then get a GT4...but...yeah...?
Coz the latest Hot4s was saying about...well...I'll quote it..."there'd have to be a really good reason for such a curious conversion and the simple answer is torque...Because of that high compression ratio, low-down grunt is phenomenal and the gobs of pulling power last well into the midrange too." Basically it's an S14 with a NA SR20DE that's been turbo'ed...like...is it just because money isn't an object...or just specifically for the SR20 motor...or...? Well...anyway...thanks for that...I'm all new to this and you guys have been REALLY helpful...thanks.
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Location:
Arthurs Creek, Victoria
Registered:
May 2002
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Re: Celica engines...
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Tue, 21 December 2004 05:45
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I'm thinking an 18rc, or a 22LE, maybe a 22RE if you even want to go that far?
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Location:
Melbourne
Registered:
March 2003
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Re: Celica engines...
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Tue, 21 December 2004 06:00
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low range torque is over rated. What you want is torque from the mid range to the top end, where you really need the power. Having lots of torque down low and sacrificing top end power makes an engine damn slow (ie 22re and most sohc engines).
5sfe = 2.2 ltre correct? but it still uses the S block, so essentialy its just a stroked 3sfe. In other words it won't rev as hard or high and its potential will be limited in comparison to a similarly modded 3s-fe.
Another thing about adding forced induction to an na engine is the compression ratios. na engines usualy have a high compression ration where as a turbo engine does not. The reason being is that a turbo engine runs boost, more boost = more power untill you start pinging. An na engine will start pinging on much lower boost than a turbo engine and thus the acheivable power on stock internals will be limited.
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Location:
Melbourne, Victoria
Registered:
December 2004
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Location:
South Australia
Registered:
July 2002
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Re: Celica engines...
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Wed, 22 December 2004 13:47
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Stroking an engine will not reduce is rev-ability (per se). There are many possible factors, camshaft layout/design being the primary culprit in this case (imho). Also, Toyota didn't exactly over-engineer the conrod/piston design because they *knew* that the scissor gear camshaft layout would be limiting. So even if you do find some way of reducing the weakness in the camshaft layout, then you will have to start looking at the bottom end set-up too.
You will also find that the 3S-FE is as equally unrevable as the 5S-FE. In fact, some 5S-FEs are more revable (although less powerful) as they added balance shafts to reduce a vibration (or harmonics or free moments of inertia whatever you want to call it).
I'm not sure why your car has a 3SFE in it, because almost every celica ST184 in Australia came out with the 5S-FE.
As for turbo-ing the 3SFE...afaik one thing is that no GE intake manifold bolts up to the FE heads - so you won't be able to use a 3S-GTE intake manifold. I'm not certain, but I am going to *guess* that the exhaust manifold bolt pattern is the same between 3S-FE and 3S-GE engines, I wish I could confirm this. This means that if you can find an exhaust manifold from a 3S-GTE (pref. one from a ST185) you should be able to set up a CT26 fairly easily. CT26s are fairly common *however* they may be a little big considering what level of boost you would likely run on a 3S-FE engine, a CT20 or CT12 might even suffice, but I have no idea if you can actually bolt those up to a 3SGTE manifold (anyone know more?).
Further more, 3S-FE injectors are pretty weak - I think they are around 300cc or less - maybe 270? this is more than likely going to be a big issue. One thing, the 3S-FE runs at least 9.0:1 compression, your intake charge is going to be *hotter* than before (compressors tend to heat up the air rather than increase density of the air), so you can see how this is a tuning disaster waiting to happen. Also the combustion chamber/piston crown shape of the FE engine is probably not the best for turbocharging - I'm fairly sure that heat will tend to build up around the spark plug area due to the low speed of flamefront propagation (pent roof + dish piston = no squish <- my understanding here is limited at best so I'm sure others might know better). Even with decent intercooling the intake charge is just going to get hot, which means you want more inert matter to absorb the heat, rich mixtures will help (but to acheive this you will be pushing the limits of your injectors), water injection and decent exhaust gas management could also help.
Lastly, you've got the engine management to take care of  No mean feat, your options here are limited - either spend a fortune and get something programmable, DIY with a megasquirt, or try stuff like SAFCs ???
I can only really scratch the surface as a) I'm not a professional most of what I have learnt has been from hours of reading various crap on this forums and b) I have never done an NA turbo conversion before.
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He he...thanks for that...and...so...from the last post...am I right in thinking that, coz you said how the 5SFE is just like a stroked 3SFE and therefore won't rev as hard or as high...does that mean stroking has that effect on engines? they won't rev as hard or as high?