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Cyclone engine?

ok soooooo i took the galant in for a new timing belt, head gasket, valve seals, and water pump.

i get the car back and the cars running all messed up and the check engine light was on.

i drive down the road after i told them to fix it and they said bring it back tomorrow and then all of a sudden nothing


the timing belt tensioner pulley let go and the motor blew

so now the garage gets to suck it up and find me a new motor...

they fired the mechanic and found a cyclone engine apparrently

anyone have any write ups on these since i cant find much and when i searched nothing really came up
 
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VR4coop

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What garage did you bring it to? And what are you looking for info about, re-builing the motor?
 

The cyclone engine isn't different from the standard 6-bolt that comes in our cars. Same crank, rods, pistons, head. Cyclone refers to the dual runner intake manifold. It came on the JDM cars. More than likely they got you a used JDM engine or a USDM engine with a cyclone manifold. I've even found some Hyundais at the junkyard that said cyclone on the manifold.

I'd give the engine a once over before they install it.
 

I think he's referring to the Cyclone jdm engines, and how are they different from USDM VR4 engines, and what is involved in swapping it in. All of that info should be in the How-To & Info Archives, so I suggest browsing or searching there.

To get you started, some jdm engines have 510cc injectors and a small 16g turbo, but that's not a big deal and the car will run fine with those. They don't have EGR and have a different TB than US cars, but you can just use your stock TB with it's sensors and the car's original wiring harness. The Cyclone manifold is mainly what sets these engines apart. It has dual runners for each cylinder, so one runner per valve, essentially (still only 4 ports in head). Have of them have throttle valves in them on a common vacuum actuator. The jdm ecu controls a solenoid that controls the vacuum actuator via a vacuum canister. Basically the system keeps the throttles closed under certain rpms and boost, load etc. to increase intake velocity as well as cause the intake charge to spin around the combustion chamber. Then when the turbo is spooled the throttles open up, giving maximum flow. You can use your USDM ecu and harness and get a Keydiver chip (www.dsmchips.com) to open up the solenoid, I believe 4100 rpm being near the ideal switching over point.

Or you can just use your US intake manifold and TB and be done with it. /ubbthreads/images//graemlins/shocked.gif

Edit: I type too slowly.
 
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464/2K

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most likely if the motor has a "cyclone" manifold it means its got 450cc's and a 14b, nothing special. if it doesnt say "cyclone" then you need to worry about getting a chip. and yes you will need the chip or the car will run so damn rich.
 

If you put the jdm engine in w/the Cyclone manifold and your US TB, yes the car should run fine, but not optimally. With nothing to control the vacuum canister/actuator, the throttles will just move according to manifold pressure, which is I believe closed under vacuum and open under boost. You can install the chip and set it up properly later if you want. If you decide to just swap over your US manifold for time and simplicity's sake, you can always sell the Cyclone on here for some extra cash to offset the repair bill. People are often looking for one.

Edit: Slow typing FTL. If the engine comes w/450's and a 14b, what would make run so damn rich?

2nd edit: vacuum effect on butterflies corrected. Thank you Jim.
 
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464/2K

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no i mean if its a jdm motor and it doesnt say "cyclone" if it says something like
"EcI multi" turbo
intercooler

mitgalvr4240rs25.jpg


looks like this
 

464/2K

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flash4gg.jpg


this one comes with 450's/14b
 

number3

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CutlassJim

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My cyclone intake mani looks like the one in the top photo, i.e. it doesn't say Cyclone. Conversely some say cyclone and are regular single runner manifolds.

The valves are CLOSED under VACUUM and OPEN when the is none.

If you hook up a vacuum line to the actuator the car will run fine and you will never notice a thing. You just won't get the benefit of the dual runners.
 

belize1334

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^^ If you hook up a vacuum source to the runners they will always be closed if the engine is pulling vacuum and always be open if it is under boost. That is NOT how the runners are intended to operate. In many instances you will get the advantage of the dual runners, but sometimes you wont. For example, you can build boost below 4100 rpm and the runners will open when in reality you want them to still be closed at that point. If you're not gonna operate the runners correctly just leave it unplugged and it'll behave EXACTLY like a USDM manifold. Alternatively, if you want to hook them up correctly there's LOTS of info on this board and it can be done relatively painlessly.
 

CutlassJim

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Quote:
^^ If you hook up a vacuum source to the runners they will always be closed if the engine is pulling vacuum and always be open if it is under boost. That is NOT how the runners are intended to operate. In many instances you will get the advantage of the dual runners, but sometimes you wont. For example, you can build boost below 4100 rpm and the runners will open when in reality you want them to still be closed at that point. If you're not gonna operate the runners correctly just leave it unplugged and it'll behave EXACTLY like a USDM manifold. Alternatively, if you want to hook them up correctly there's LOTS of info on this board and it can be done relatively painlessly.



The runners will always be closed if the engine is pulling vacuum, true. But the runners will open PROGRESSIVELY with less vacuum and will be open all the way with no vacuum. Note that if you floor it, even at 1000 rpm when you don't make any boost, the runners will open, acting just like a stock 1G manifold.

You could leave it unplugged and it would act just like a normal manifold too but in a case where your only at %25 throttle at 2000 rpm, i.e. cruising, and pulling 10-12 inches of vacuum still, why not have the valve hooked up and reap some of the benefits of the manifold? /ubbthreads/images//graemlins/dunno.gif That is until you get it hooked up correctly. If you have no intention of ever hooking it up properly then put on a stock 1G manifold and be done with it.
 

atc250r

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If those idiots couldn't do a timing belt job I would NOT let them install my motor. I'd make them pay a COMPETENT Mitsu shop to install it.

John
 

atc250r

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Besides, should this be in Newbies too?
 

Bimmubishi

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Maybe they could find you a head if the pistons aren't damaged. What exactly let go? Did they forget to tighten the eccentric pulley or did the pneumatic tensioner fail?
 

H05TYL

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note: ECI multi inlet manifolds found on 'Evo0' 4G63's still have the dual runner cyclone setup with the butterfly valves in the runners. (yea I was suprised too).
 

im not sure exactly what let go i was just told the tensioner pulley... i havent looked at the motor yet

they had ordered one this week so theyre waiting for it to arrive

when it arrives ill check it all out and let you guys know what manifold it has,im assuming the one that says cyclone on it though

im not paying for the labor or the motor at all so im gonna take what i can get as long as its fixed correctly. if i had the money id take it somewhere else but i am flat broke right now and it sucks im sure you guys know the feeling /ubbthreads/images//graemlins/tongue.gif
 

grocery_getter

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A local honda shop did a cams swap job on an evo and didn't tighten the tensioner pulley properly. It turned loose and bent all the exhaust valves. It pays to pay attention to your work!

Andre
 
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