As the title states. Thanks. Is there any way to make an Si engine (K20A2?) internally identical to the RSX Type S?

 

swap complete head with cams (3 rocker arms instead of 2 with si)
up compression with pistons from 9.8:1 (si) to 11:1 of the rsx-s
crankshaft is different
rods in type s are beefier
will also need ECU.

if building up the k20a3, you might as well go crazy. make compression 12:1 port and polish....everything. otherwise you are better off just buying the type s engine.

 

Just sell your engine and buy the type S.

 

is the civic k20a3 engine exactly the same as the base rsx engine?
if so...how could you make the auto produce 280hp without FI?

 

the Si head also have only ONE vtec cam, i believe it's the intake side.

 

just buy a Type-R engine

 

where can i get a type-R engine without getting rip up the *** for it?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote"> where can i get a type-R engine without getting rip up the *** for it? </TD></TR></TABLE>

You can get the complete swap from JDMhondaparts for $6500

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by epthree &raquo;</TD></TR><TR><TD CLASS="quote">swap complete head with cams (3 rocker arms instead of 2 with si)
up compression with pistons from 9.8:1 (si) to 11:1 of the rsx-s
crankshaft is different
rods in type s are beefier
will also need ECU.

if building up the k20a3, you might as well go crazy. make compression 12:1 port and polish....everything. otherwise you are better off just buying the type s engine. </TD></TR></TABLE>
You forgot the one piece Intake Manifold on the K20A2.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eg_nezay &raquo;</TD></TR><TR><TD CLASS="quote">

You can get the complete swap from JDMhondaparts for $6500 </TD></TR></TABLE>
indeed... wish i had that kinda money.


Modified by Sleeping4drLS at 5:20 PM 5/31/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eg_nezay &raquo;</TD></TR><TR><TD CLASS="quote">

You can get the complete swap from JDMhondaparts for $6500 </TD></TR></TABLE>

hmotorsonline.com: $5,800.

 

I never said I would buy it and I wouldnt buy it, that guy simply asked "where" to get one from.

Also, if I wanted an R motor that wouldnt be my price

Besides, Im going turbo for half that price and more power

 

 

Umm....Whats the function of that reply?

 

If they're talking about a K20A from a JDM DC5-R it's more like a 55 hp move.

And an EP3 purchased for $16K plus a $6,500 complete K20A swap comes out to about the base price of an RSX-S. An RSX-S plus the Hytech engine kit comes out close to the price of a new STi or Evolution VIII. So I can see why the owners of the respective cars have different viewpoints.

 

Differences include:

- higher compression pistons in the K20A2
- two completely different i-VTEC systems

I've also heard that the bottom end (crankshaft and rods) of the K20A2 are slightly different, but I don't know how true this is. Perhaps someone who has torn both of these engines completely down can confirm whether or not this is true . . .

All you ever needed to know about the i-VTEC differences between K20A2 and K20A3 engines:

The K20A3 does not have a standard DOHC VTEC valvetrain as we know it from the B-series engines - the K20A3 should actually be called a "DOHC i-VTEC-E" engine, because it uses a VTEC-E cam setup. The K20A2 is the "real" DOHC i-VTEC engine, utilizing the standard DOHC VTEC cam setup we're all familiar with. To help you understand the differences between the K20A2 and K20A3 engines, I've included the following information from a post I made elsewhere:

Allow me to evaluate. Let's start out by defining some terms:

VTEC - Variable valve Timing and lift Electronic Control. At low RPM, a VTEC engine uses a normal cam profile to retain a smooth idle, good fuel economy, and good low-end power delivery. The VTEC mechanism engages a high-lift, long-duration "race" cam profile at a set RPM value (i.e., ~5500RPM on the B16A) to increase high-end power delivery.

VTEC-E - Variable valve Timing and lift Electronic Control for Efficiency. This system isn't really VTEC as we know it. At low RPM, the VTEC-E mechanism effectively forces the engine to operate as a 12-valve engine - one of the intake valves does not open fully, thus decreasing fuel consumption. At a set RPM value (i.e., ~2500RPM in the D16Y5), the VTEC-E mechanism engages the 2nd intake valve, effectively resuming operation as a normal 16-valve engine. Note: in a VTEC-E engine, there are no high-RPM performance cam profiles; this engine is supposed to be tuned for fuel economy, right?

VTC - Variable Timing Control. This is a mechanism attached to the end of the intake camshaft only which acts as a continuously variable cam gear - it automatically adjusts the overlap between the intake and exhaust cams, effectively allowing the engine to have the most ideal amount of valve overlap in all RPM ranges. VTC is active at all RPMs.

i-VTEC - intelligent Variable valve Timing and lift Electronic Control. This is a combination of both the VTEC and the VTC technologies - in other words, i-VTEC = VTEC + VTC. Currently, the only engines that use the i-VTEC system are the DOHC K-series engines.

Now this is where things get tricky - Honda uses the term "DOHC i-VTEC" for two different systems: The first system is used in the K20A2 engine of the RSX Type-S. The second system is used in the K20A3 engine of the Civic Si.

The First System (K20A2):

This system is pretty close to the older DOHC VTEC engines. At low RPM, the K20A2 uses a normal cam profile to retain a smooth idle, good fuel economy, and good low-end power delivery. At 5800RPM, its VTEC mechanism engages a high-lift, long-duration "race" cam profile to increase high-end power delivery. The only difference between this i-VTEC engine and the older VTEC engines is the addition of the VTC system. The intake camshaft has the automatic self-adjusting cam gear which continuously optimizes valve overlap for all RPM ranges.

Here we see an image of the intake cam lobes of the K20A2. Notice there are 3 lobes; the two side lobes are the low-RPM profiles, and the center lobe is the high-lift, long-duration profile which engages at 5800RPM. Basically the same setup as the old VTEC engines we are familiar with.



Now here we see the VTC mechanism - the gear on the end of the intake cam that adjusts valve timing (overlap) automatically on the fly.



This system is used in engines powering the JDM Honda Integra Type-R, Civic Type-R, Accord Euro-R, and the USDM Acura RSX Type-S and TSX.

The Second System (K20A3):

This system does not really conform to the "DOHC i-VTEC" nomenclature, as Honda would like us to believe. As I mentioned in my previous post, it actually should be called "i-VTEC-E," because it uses a VTEC-E mechanism rather than a standard VTEC mechanism. At low RPM, the VTEC-E system effectively forces the engine to operate as a 12-valve engine - one of the intake valves does not open fully, thus decreasing fuel consumption. At 2200RPM, the VTEC-E system engages the 2nd intake valve, effectively resuming operation as a normal 16-valve engine. There are no high-RPM performance cam profiles; this engine is tuned to balance fuel economy and power, rather than provide pure performance. On the intake cam, there is the VTC mechanism which basically is an automatic self-adjusting cam gear used to continuously optimize the valve overlap for all RPM ranges. This being a VTEC-E system - and not a true DOHC VTEC system - is the reason the K20A3 redlines at a measly 6800RPM, while the K20A2 is able to rev all the way to 7900RPM.

Here we see an image of the intake cam lobes of the K20A3. Notice there are only 2 lobes - there is a nearly round one used only for the low-RPM disabled intake valve, and then there is the regular lobe used by the other valve at low-RPM and by both valves at high-RPM:



This system is used in engines powering the USDM Acura RSX base, Honda Civic Si, Accord 4-cylinder, CRV, and Element.

Special note: The K20A3 engine used in the Acura RSX base has a slightly different intake manifold design from the K20A3 engine used in the Civic Si. The RSX engine uses a dual-stage manifold, similar in concept to the manifold of the B18C1 in the old Integra GSR. It uses long intake runners at low-RPM to retain low end power, and switches at 4700RPM to a set of shorter intake runners to enhance high-end torque. This accounts for the extra 9 ft-lb of torque in the RSX (141 ft-lb, vs. 132 ft-lb in the Civic Si).

Here is an image showing just how this dual-stage manifold works. On the top, you can see the low-RPM (long) runners are in use, and on the bottom, you can see the high-RPM (short) runners in use.



Myths:

1. The i-VTEC engine engages VTEC gradually, and not suddenly like in the old VTEC engines.

Wrong. The i-VTEC engine "engages VTEC" at a single set RPM, like always. Whoever started this rumor is a fucktard. Read the definitions above.

2. VTC engages at a set RPM.

Wrong. VTC is always activated. Read under "VTC" above.

3. The K20A3 engages VTEC at 5000+ RPM.

Wrong. Technically, there is no "VTEC" (as we think of it) in the K20A3 engine - it uses a VTEC-E technology, which engages at 2200RPM. Read under "The Second Sytem" above.

* * *

Sources of pictures and information (good reading material):
http://www.leecao.com/honda/vtec/index.html
http://www.hondata.com/techk20general.html

Here are some bigger pics of the two different heads:
http://ephatch.com/forum/attac...92101

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tofu DC5 &raquo;</TD></TR><TR><TD CLASS="quote">is the civic k20a3 engine exactly the same as the base rsx engine?</TD></TR></TABLE>

They are the same engine (K20A3), they just have different Intake Manifolds.

 

That's some great info, Targa. Someone should take that and make it a sticky for this forum.

 

great info

I understand the K-series engine as well as the i-vtec more now after reading your post

 

Outstanding. That's quality content!

You don't happen to do technical writing as a profession do you?

 

Very nice, that was a much better answer than "Just get a Type R swap".

Thanks!

 

Targa250R: Nice post! That's a lot of good info!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sjracer &raquo;</TD></TR><TR><TD CLASS="quote">Targa250R: Nice post! That's a lot of good info!</TD></TR></TABLE>

 

thanks Targa250R

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sjracer &raquo;</TD></TR><TR><TD CLASS="quote">Targa250R: Nice post! That's a lot of good info!</TD></TR></TABLE>