Hopefully SlowBoy will see this thread an add some info. As they turn there 2.4l to 9k or so.

 

i always wondered how high there stage 2 std2.4 could rev as they dont indicate it also how much tq the built block could actually handle

 

But that's only one data point.

There is a video around of a turbo K24 on a Dynojet that churned out 1115whp@8800rpm and 765ft/lb with a GT42X, E85, and a stock head. I feel that speaks for itself.


No matter how one chooses to slice and bemoan all the intricate engineering differences, the largest functional difference, as far as I see it, lies in the flow potential of the Honda's head.

 

You might be talking about TD Autowerkes White EK

www.youtube.com/watch?v=aFAEAMyzYqU
http://www.youtube.com/watch?v=xA2AVuyOaXw


http://www.k20a.org/forum/showthread.php?t=77839

 

You are right Erik, and thank you! I'm sorry that people are being rude to you!

First off I doubt you are as likely to throw a rod unless you are pushing the limits on the rods... However you will destroy the bearings. I think that is where we need to be focusing on and the heads as well.

Bingo! Magnus didn't make a $5,000 dollar oil pump/dry sump for it to be a paper weight! I think that is the reason why people revving the 2.3 and 2.4 so high are burning up the bearings. They are losing the oil pressure and the days of having an AMS pan and assuming it fixes everything is OVER!

Mikey

 

Here's a slight tangent. If the OEM pump is having trouble maintaining oil pressure at higher rpm's, has anyone taken apart an OEM pump to modify it and/or thought about some kind of metal treatment (like a coating) to possibly make it more efficient?

Just curious.

 

I believe it's a combination of things:

*Cylinder Head-the design & ability to flow and support HP @ higher RPM along with supported valvetrain components to sustain it with suitable cams.

*Rod/Stroke Ratio-the ability to fill the cylinders @ higher RPM as well as reducing cylinder wall stress.

*Oil Pump-to support high RPM without failing.

*Rotational Mass


Would it be better to compare the F22/F23 to the 4G64 as far as R/S goes(1.49 vs 1.50)?

 

Most of the recent Evo 2.4 builds are done with 156mm rods, hence the reason for the OP to wonder about the K24/K20.

K24 - 99mm stroke, 87mm bore, 152mm rod, 1.54 r/s ratio

4G64 (LR) - 100mm stroke, 87mm bore, 156mm rod, 1.56 r/s ratio

 

I see. In that case, that will take care of rotational mass and R/S ratio so that's leave the most important aspect: cylinder head.

Any data on a LR2.4 using a 1G head?

 

Ya, and I can turn my LR2.4 to 11k but doesn't mean it will turn over the next time I try to start it... Honestly I think a well set up 2.4 can rev to 9k no problem but a lot of things would have to be done to ensure flawless operation. I'm not talking about once or twice down the track. I'm talking about every day, all day, on the road!!! That is what most of us care about!

Erik, honestly I would be willing to bet Marco has!!! Marco thought that the stock oil pump was a big enough problem that he designed a whole new oil pump/dry sump for $5,000.

Makes me wonder if Kevin has actually tested the pump and tested the oil pressure at 9200 where he redlines and he is even planning on going higher. I would be willing to bet he is losing a good deal of pressure considering the pump is really only rated for maximum of 8000 till pressure starts to fall off a considerable amount.

I'm not doubting Kevin's engineering but why would Marco go through all the trouble and install it on the Magnus 2.3L they were testing a while back if it wasn't needed??? However, Kevin runs 9200 and says the pump is not the problem but yet still burns up his bearings, it may be the rotational weight more than the oil in Kevin's case, but I have no clue. He is even running oversied bearings and an aftermarket crank with more oiling capabilities while still destroying bearings.

If I had the money/turbo to turn my LR2.4 to 9k I would just to test out the pump and bearings. However, I know what I would end up doing that should allow it to rev to 9k fairly safe.

1) Head would have to be worked to the extreme without going into the water jackets.
2) More aggressive cam with a higher lift
3) Magnus oil pump/dry sump kit
4) Oversized bearings
5) Magnus Billet Crankshaft
6) Ti rods 210grams lighter per rod (159mm)
7) Wiseco Custom pistons (New design-stronger, lighter, and dissipates heat better than the current HD1400s)
8) Oil squirters

All that together: We will have the oiling problems addressed, the head addressed as best possible, Removed more than 1000 grams from the rotational weight, made the r/s ratio a bit better a 1.575. (a bit extreme to fit a larger rod in the block and sacrifice the piston strength, however Wiseco doesn't seem to think it will be a problem with the right piston design and material). The oil squirters will only be there to cool the pistons due to the fact of having to run an extreme CH for the 159mm rod and with the Magnus oil pump we wouldn't be worried about losing oil pressure in higher rpms. Also, a longer rod provides for better combustion in higher rpms however I doubt we would see a benefit going from a 156 to 159mm rod.

After doing all of the above, this should lessen the side load, re-leave a lot of the stress on the bearings at 9000+, and provide the airflow and oiling that our motors need... Maybe I'm just thinking in a perfect world but it would seem that everything would work, however I will never have the money to test this!

I hear the larger angle ports will kill lowend and I hear that it is not as efficient in higher rpms... Anyone know for sure?

Mikey

 

I have to assume you are talking about this?

If so, please point out where I said anything about "the street" or "the grocery store."

 

If the head is the problem, time for a k series head swap to a 4g64, HAAHA. Im joking.

Anyways if money wasnt a concer you could have a custom head made, with a new intake and exhuast port/size design, basically redesign the head to flow more like a honda haha.

 

The bottom end of both engines, spec wise, are covered. So let's look at the heads. IIRC, both valve angles are 45* with the k20 head have 35mm intake valve and 30mm for the exhaust. The 4g63 has a 34mm intake and 30.5mm for the exhaust. Both heads use roller rocker arms. What is unknown are things such as port diameter, port shape, bowl area, port angle, etc.

Cams for K20 have an advertised duration of at least 300* and lift at least 12mm, so in order for a LR2.4 to produce power above 8000rpm will need a duration of at least 280* and 11mm valve lift. Will the stock lifters handle that abuse? May need to switch to solid lifters and cams.

Didn't Mitsu produce some high rpm four bangers such as the 4g61, 4g67, and 4g91/2 Mivec? Maybe a modifed oil pump or oil pump gear from the above engines can solve the oil starvation than buy a 5K dry sump system.

 

We can't really equate the bottom end of one to another without some real scrutiny. Important aspects such as bearing diameter and width, crankshaft oiling (Mitsu leaves something to be desired), and such are not considered here. FWIW however, the turbo K24s seem to keep revs <9k rpm, and no doubt for good reason.

The 4G63 has an included valve angle of 57 deg. I don't know about the Honda, except that it outflows the Mitsubishi head by a comfortable margin, and seems to be a very efficient design.

What makes it tough on hydraulic lifters are steep ramp angles. So far, that hasn't seemed to be an obvious issue here.

 

What about a totally redesigned bolt on billet head similar to the 3RZ guys?