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Twin Cam Engines

Posted: Thu Jan 15, 2004 12:48 pm
by tmz_99
Ok.. obviosly anyuthing above an evo3 is a no go, so what are the differences in the VR4, RVR, Evo 1-3 engines (domestic and Jap)?? Internals wise, power wise, etc?? (ie: which would be the ideal engine to start a conversion with?)

Posted: Sun Jan 18, 2004 4:57 pm
by stariontron
i think you can still use the later setups, youd just have to use the block as well.

go with the vr4 head, they dont demand nearly as high prices as the evo ones, plus the inlet ports are bigger. use an evo airflow meter if youre going to go with the factory computer as they are bigger too. but the biggest difference is price.

Posted: Sun Jan 18, 2004 6:00 pm
by Project2501
So, in effect, the oil galleries and water jackets of the VR4 head line up with the Starion block? If this is the case it would make planning so much easier...

cheers

tom.

Posted: Sun Jan 18, 2004 8:27 pm
by NXTIME
Yes, the head will bolt on; oil and water galleries all line up. But that is only the beginning of what is required. I would also recommend a VR4 head for the same reasons that Stariontron mentioned.

Posted: Mon Jan 19, 2004 5:37 am
by Project2501
yes im guessing there is a whole lot of custom work to be done, but if the head matches the block then its a first step... :twisted: just give me a few years...

cheers

tom

Posted: Wed Jan 21, 2004 12:36 am
by StarionChef
Can we have a section for this somwhere? Seems to be all poeple want to do. A sticky or something would be good

Posted: Wed Jan 21, 2004 1:29 am
by decoy
will hopefully have a tech article on the webpage for a vr4 conversion. I'm going to host an article of putting a vr4 into a scorpion and all the main things that need to be changed. not exactly the same as a starion but covers a lot of changes that need to be made either way.

Posted: Thu Jan 29, 2004 3:32 pm
by SpidersWeb
The VR4 motor, with TD05 16g, will happily run up to 18 psi of boost. So I'm hoping the VR4 block has the same mount points, thereby saving a rebuild of the Sirius block with VR4 internals and head. If I can't use the VR4 block, I think it'll be JE Forged + VR4 head.

Also I heard its easier to use an EVO4-6.5 engine because the exhaust is on the other side, thereby it doesn't hit the steering box. But never asked how many extra problems this would cause.

vr4 block...

Posted: Thu Jan 29, 2004 9:12 pm
by Paradoxx
The block still has the engine mount points on it from when they developed the vr4 engine 9i guess they couldnt be bothered removing them) so it pretty much bolds straight in. only thing is u will need a custom exh manifold to sit the turbo higher, and the water pipes will need to be redirected. I would recommend leaving the vr4 head with its block, there are subtle differences between them and the staz block.
I have pics if anyone needs em.

Steve.

Posted: Thu Jan 29, 2004 11:04 pm
by decoy
we need pics... along with a whole step by step conversion article! :D

Posted: Fri Jan 30, 2004 11:29 am
by SpidersWeb
I also heard you had to 'dent' the firewall to fit the sensor in there (not sure if it was cam-angle or knock).

Also I guess you'd have to re-loom the car for the new ECU?

ECU

Posted: Fri Jan 30, 2004 3:10 pm
by Paradoxx
Basically yes, u need to rewire the loom, but the easiest way is tap into the existing loom (where the original computer goes) and only cut the wires you need to, that way exerything under the bonet is connected already. The starion ecu wiring diagram is a must (i think i have one here somewhere...)

Steve.

Posted: Fri Jan 30, 2004 4:20 pm
by mrb1
Paradoxx,
you forgot to tell him the gearbox won't fit with the VR4 engine! The VR4 block has the "narrow" front wheel drive type bellhousing. There is also no way the Starion ECU will work. Have to go aftermarket ECU (which I guess a lot of people already have). The VR4 has an optical trigger with two outputs which the ECU must be setup for. The ECU must also be capable of direct fire ignition. You then also need a two channel ignitor or two single channel ignitors or a 2 channel CDI unless your ECU has the ignitors built in like some Microtechs. You also need two double ended coils if you did not get the coils with the engine.

Posted: Fri Jan 30, 2004 6:23 pm
by SpidersWeb
I was going to use a VR4 ECU

Also what the heckers you mean it doesn't fit? That was the one thing I was counting on, nobody ever mentioned that before.

How do you get it to fit??

Posted: Fri Jan 30, 2004 6:33 pm
by SpidersWeb
Starion block + VR4 everything else I guess
*curses*
means I have to do an engine rebuild and not a swap
grr

Possibly the 5 speed box from a newer model RWD van or something. Have to find if there was any utes/vans running a 4G63 motor rear wheel