Ok I'm thinking about buying a 2nd hand 3.5ltr motor. Whilst its out of the car what mods could be done without breaking the bank too much? Can they be boored out any bigger or anything similar? Like a $1000-$1500 mod!!

Chuck in 272 cams or put in the 380 cams. If you wanted a real noticeable difference though I'd get the more serious cams.

Set of Ralliart pistons are on ebay, should be direct swap in and will raise compression to 9.4:1. Think you will get the set for around $200

You may struggle to do cams with that sort of money unless you just get 380 cams, they will give you a little extra for minimal cost however with any more radical cams you will need to have stronger valve springs etc and they won't even give you too much more power without a tune which can be $500-$1000 by itself.

Why go 380 cams when you can get a 380 motor for a bit more? Make far more power and torque out of a stock 3.8

Ok I'm thinking about buying a 2nd hand 3.5ltr motor.

Wouldn't the first thing to do is check the motor to see what condition its in? Like plugs, cam belt, valves, valve stem seals, big end, main bearings, bore wear, seals, leaks etc? Might come from a low Km car, but then again it may have been sitting around for a long time . . . . I wouldn't spend money on "improving" a second hand motor without first checking it out thoroughly.
You would feel silly if you put it in, 380 cams and all, then found it runs on 4 cylinders because some valves aren't seating through corrosion.

^ im with madmax, spend the money on a thorough service and then I say save the rest. Arguably you could spend $500ish on a tune, but even then there are skeptics of the value in that.

Il be happy myself with 380 cams, extractors and an SKR tune

Why go 380 cams when you can get a 380 motor for a bit more? Make far more power and torque out of a stock 3.8

To be fair not everyone can DIY an engine transplant :P

Shaved head will raise compression ratio - no idea on price but if you can pull it apart and hand the bits to a workshop that actually does the work, I'm sure it wouldn't cost much.

Oh, if considering this, make sure there is no risk, or at least an acceptable one. I can think of valves hitting piston either from taking too much off the deck or if timing belt is ever way out or broken and maybe there coolant passages, head bolt lengths etc could have an issue.


Still thinking ... ages ago (maybe 15 years) I paid an automotive engineeering company about $3200 to remove, rebuild, modify and replace my 4 cylinder engine after I'd killed a big end bearing.

It included a 40 thou re-bore, oversize pistons & rings, port & polish, shaved head and I think balanced crank (maybe rods too?)

In the end the car sounded mean (strangely, it sounded like a WRX).
But unfortunately it wasn't any faster at the drag strip because I added leads and a ceramic clutch sourced from MRT.
I put the factory 4mm leads back on and improved times by 0.5 seconds to get back to standard, but clutch slip prevented it from being faster ever again in it's life. The ceramic clutch cost about $600, plus $2k to replace with factory clutch & flywheel when I was stranded interstate about 3000 kms later.
And even with the factory clutch & flywheel, the bite wasn't good enough for the engine so performance still wasn't quicker over all.


If you're serious, I'd recommend getting the engine checked, as per other's suggestions, and from there you could look at blue printing, balancing, lightening rods and maybe crank, port & polish (extrude honing rings a bell), port matching, adjustable timing gears for the cams, cams
NEW PLUGS while you have access to the rear bank!

But if you make too many modifications, I believe you'll need an ECU re-tune to make the most of them. And if these aren't off the shelf changes, then it means a real tune with Dyno time. ballpark I think SKR does this for <$700, but that doesn't leave much from a budget of $1500 for the other mods.

Have fun!

timing belt if its getting close, any seals you can't get to easily with the engine in the car, a good clean.

I believe a postal tune by SKR is around $350? Dyno is $500-$570 for a tune

+1 for the 380 conversion. If you are looking at $1500 in mods to a 2nd hand engine you've bought, lets say you've paid $300 for this engine (being conservative here), for $1800 you could easily get a 380 motor which has more power/torque and already has all the mods done to it you can do to a 3.5L for that kind of money.

-1 for the maths on the 380 conversion :)

Once you've paid about $1800 for the 380 motor, can it be put into the car as easily as the 3.5L one? I think swapping of coils, dizzy, sump and/or other stuff has to happen before it can be used in the car - all of that will add to the cost. But it still might end up a lot better than a modified 3.5L engine for price & performance.

380 engine can be had for $1000 if you shop around, add $500 in consumables (timing belt, plugs, oils, seals), use all the existing gear off your 3.5L, and minimum $1000 labour.

End of the day - $2500-3000 fitted for a 30kwfwkw gain.

Less then half the price of a blower for the same power figure, double the reliability.

$3000 dean.. less then half the price of a blower. Somehow i think i could fit a blower for just over 6g and gain a little more then 30kw..

So the 380 motor uses same mounting points etc? Straight swap over? Is this what I'm hearing?

So the 380 motor uses same mounting points etc? Straight swap over? Is this what I'm hearing?

yep. The 380 motor is basically the same as the 3.5l motor but with internal changes and some other bits and pieces.. but mounting points are the same

yep. The 380 motor is basically the same as the 3.5l motor but with internal changes and some other bits and pieces.. but mounting points are the same
Well this changes EVERYTHING

$3000 dean.. less then half the price of a blower. Somehow i think i could fit a blower for just over 6g and gain a little more then 30kw..
Say bye bye to your motor unless you strengthen the bottom end as well. But yeah I'd go for the 380 motor I gained over 20kw without a proper tune!

And gained a shitload of low down torque! /\

Other then the engine what else is required? I know its morth it for the gain but just needing to know what else is involved?

Tj vrx tippy box work on a 380 motor?

What if you have quad cam will the 380 cams still fit even thow ill need four of the thing?

Tj vrx tippy box work on a 380 motor?

Dont see why it wouldn't fit... the mounts are all exactly the same.


What if you have quad cam will the 380 cams still fit even thow ill need four of the thing?

Quad cam off what?? No it wouldnt work as two cams are for intake and two are for exhaust instead of one for each bank being for both exhaust and intake.

Errrr quad cam usually means twin cam on each bank, its not a true quad cam. Dont know which motor you refer to though, as All magnas are SOHC

Errrr quad cam usually means twin cam on each bank, its not a true quad cam. Dont know which motor you refer to though, as All magnas are SOHC

He's probly looked at the sticker on his engine cover (quadtech) and got it mixed up? thats if he drives an AWD.

perhaps!

yeah he drives an awd...