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mesobitchy
18-01-2010, 10:18 AM
What is the MAX power handling that an unplayed with V6 engine can take, before having to upgrade and re-sleeve parts of the engine?

also what RWD boxes can be hooked up to the V6 engine?
thinking a showgun maybe?

of course this would mean turning the engine around in the bay, rather then leaving it as it is and adding one of them fancy doohickery boxes.


mazz

Turbo_Steve
18-01-2010, 02:30 PM
It's just not worth it, Maz!
By the time you've spent out on cams, porting & polishing, bespoke tuned ECU, inlet and exhaust headers, put in a much higher grade oil to allow for raising the rev limiter, potentially lightened the valves, stronger springs, uprated the cambelt and tensioning, you may as well have just dumped a different engine in there.

Same goes for the transmission, really: turning the engine around by 90degrees is a HUGE proposition: the cost of hoses and pipes and wiring alone is going to be approaching equal to that of fabbing up new mounts and subframe, as well as probably getting a custom bonnet made to allow the engine to tip up (which it will).

Then you've got to mate the bellhousing to the new transmission, get some rear hubs, axles and diff from a VR4, and somehow make the proshaft talk to your new transmission. It's a mammoth conversion, and I woudldn't take it on.


You'd probably do better to get the RWD parts from a VR4 and mate them to the rear of your V6, and go from there, though I would imagine you're talking a lot of work: petrol tank will need to be swapped for a VR4 one to allow for driveshafts, and that means the plumbing and everything else needs to be checked.

The easiest way to get a powerful RWD Legnum is probably just to buy a VR4 and remove the bits you don't want: i.e. front shafts and diff and cap off the box.

If you really want a different engine, buy a Vr4 with a dead engine and mate a 4G63T up to it from an Evo. 4cylinder turbocharged fun, easily modifiable.

mesobitchy
18-01-2010, 02:37 PM
we was talking last night about a few things, and one of them was how much power can a V6 engine take, before we have to go down the road of up grading.

and we know it is a mammoth task for turning and converting to a RWD,
this is just a little project play thing.
rwd is for something else. and it dose involve getting a vr4 chassis.

there is a method to my madness :D

but the main question is still about max power to the standard v6 engine.

IE: the standard engine put out roughly ~160-ish BHP, what is the higest it can be pushed to?

on my old mazda there was talk of a 150BHP being pushed to 200 with out the need of upgrading the internals.
so i am wondering what is it for this engine?

miller
18-01-2010, 04:08 PM
isnt that a hypothetical question that will never receive an exact answer?

mesobitchy
18-01-2010, 04:33 PM
no, how is it?

im just curious to know what the standard engine can achieve.

cos all you seem to read on here is what the bhp a vr4 is/can do/done.

miller
18-01-2010, 04:34 PM
181.567bhp

WildCards
18-01-2010, 04:36 PM
The trouble is, if nobody has taken a standard engine to it's limits, how do you find out what they are?

It's never been done AFAIK, so an accurate answer can't be given. I do seem to remember Slim Shady's V6 made 195ish hp on a rolling road in 2006.

bradc
18-01-2010, 07:18 PM
The rods and crank are the same part numbers as on a VR-4. So they'll handle more power that what you could ever make. In a VR-4 they are capable of revving to 7000rpm and I regularly take my ST-R to 7000rpm, the engine will be fine at that rpm.

The stock cams run out quite early on. The car makes it's max power at 5500-5750rpm and drops off quickly afterwards. Changing the cams could push that peak power up to 6500rpm along with an exhaust of course. This should be able to get you up to about 155kw, around 210hp.

Turbo_Steve
18-01-2010, 08:05 PM
Except that with cams that wild, it will drive like a DOG! To get more power you need wilder cams, and wilder cams mean less low down torque. If you really want to see good peak power, it's going to have to rev higher than 7000rpms.

And brad, you're assuming that the inlet manifold etc won't be a limitation, and that your "wild cam" can actually get enough lift: hydraulic lifters can only do so much before you need extensive upgrading. If you want huge lift and overlap, things need to happen faster, which means hydraulic lifters may be too slow.


Meso, NA tune is a massively complicated thing, and TBH you don't "push" an NA engine to it's limits, you allow it to breathe better.

As above, I doubt you'll ever reach the limits of your internals, but you can spend a fortune in mods trying to get an extra 50bhp, and maybe never see it

bradc
18-01-2010, 08:08 PM
Raising peak power by 1000rpm shouldn't be that difficult though, surely?

Turbo_Steve
18-01-2010, 08:17 PM
Are you talking about going past 7000rpms, or just cams?

bradc
18-01-2010, 08:20 PM
I'm talking relatively stock engine but obviously with an exhaust and decat, perhaps manifolds?

But with the only real mod being cams designed to take peak power up from the stock 5700rpm or so up to 6500rpm with cutout of 7000rpm.

psbarham
18-01-2010, 08:49 PM
i have spent many an hour looking at making a rwd galant, and without some serious, And i mean serious work to the chassis, so serous that a welder i know who does specialist work for lotus just walked away shaking his head muttering something about a new subframe from billet alli/magnesium alloy would be easier but would cost £2500+ for the billet alone.
as for a box, well anything rwd will do with an adaptor plate, for cost i was looking at the ford rwd cossie box which you can buy blank bell housings for.
And the engine, well as above the cams, heads & inlet manifold is just the start, the ignition timing is another restriction due to the fact its a fixed dizzy, then theres the ecu, well the list is endless, best bet, evo lump, pure and simple.

Turbo_Steve
18-01-2010, 09:27 PM
Brad, to move peak power, you'd start by just retiming the cams, really.
Custom grinds are obviously much better, though.
The higher you move that powerband, though, the worse that engine is going to perform at lower RPMS and throttles.

mesobitchy
19-01-2010, 02:27 AM
was thinking about upgrading the cams.
thinking well maybe throw in the VR4 ones, but cant due to the V6 being an SOHC and the VR be DOHC.
so i thought, well why not make a a mixture from the vr and put it onto the v6?
yes custom job.
but need something to take the added extra power that maybe a dule supercharger(s) can add to the V6 engine.

obviously all the engine will be moved to a vr4 chassis, so it will give room to do anything that one may wish to do as to eventually making a RWD.

again this is all talk and info gather to see what is possible,
and also something that is not going to happen over night.

psbarham
19-01-2010, 07:58 AM
obviously all the engine will be moved to a vr4 chassis, so it will give room to do anything that one may wish to do as to eventually making a RWD.



the engine bay on the v6 is actually bigger due to the smaller subframe, but that would go as part of the conversion anyway, so you might as well stick with the v6 shell, it is identical apart from all the bits that would be cut out to make a rwd car

mesobitchy
19-01-2010, 08:49 AM
there is that, but the vr fram is stonger built.
and the fule tank at the back is different to the v6 tank.

method to my madness ;)

psbarham
19-01-2010, 06:57 PM
there is that, but the vr fram is stonger built.
and the fule tank at the back is different to the v6 tank.

method to my madness ;)

the chassis is identical structurally, the only bit different is the cut out on the floor for the arse end of the transfer box. how many fuel tanks do you want? i have 2 here. and anyway if you were doing a proper build then you wouldn't use the stock tank anyway

Turbo_Steve
19-01-2010, 07:48 PM
Bloody hell, is it! No wonder the V6's feel so...so...."TOIGHT!" :D :D


I can see where Maz is coming from with using a VR4 petrol tank, though: race tanks are never as big. Don't fancy sorting out the wiring much, though :(

Have to confess that as projects go, it's level of pointlessness is EPIC.

You WILL spend a fortune on parts to get big power (a supercharger (and you do NOT use two superchargers) will cost more than a VR4 engine.
If the economy is bothering you, then a 4G63T is marginally more expensive, smaller and easier to work with, and a hell of a lot cheaper to run. It's a better platform for modification too! It isn't such a nice engine to live with, though, but how deep are your pockets.

A supercharger is going to set you back more than £1200 just for the compressor - much more if you want a full roots blower (and good luck finding room for that in the engine bay with a longtitudinally mounted V6!!!)

I'm not knocking what you're thinking, Maz, but as conversions go you're talking a truly mind-raping amount of fabrication, difficulty and expense.

It really would be easier just to buy a VR4 and take out the front driveshafts and change the rear diff for non AYC. In fact, there is a non AYC VR4 in the country for sale RIGHT NOW which would be perfect!!!!

So, we're looking at around £20,000-£25,000 to do the work on a V6 (including a supercharger, longtitudinal V6 and RWD).
We're looking at £2500-£3000 for a VR4, and maybe another £2000 to get rid of the front shafts (likely to need a gearbox rebuild).

So you're at least £15,000 better off.....you could fit bigger turbos and an ECU to give you V6 like economy on cruise, and EPIC levels of RWD power output....£15,000 could buy you a pair of TD05-18Gs, a fully forged engine and all the rest of the stuff to get you to 800+bhp.

Roberto
20-01-2010, 03:16 PM
Well Excuses Me For Info Gathering !!

Gathering info on this reminded me of something very important:
http://www.youtube.com/watch?v=TCEsVNv4XAk

/Hijack over

But would it be easier to get a powerfull RWD chassis and try to graft a Galant/Legnum body onto it?

Just something else to think about.

mesobitchy
20-01-2010, 03:50 PM
RWD is something i wont mind, but it is also something that can wait.

the more important question about the engine and its parts was thankfully answered by brad.
and if anyone has more info along the lines as to what he has said then it is wecomed.

miller
20-01-2010, 06:01 PM
but all that work for just that end product?!?!?! which is why the sceptism is kicking in.

Spend £30k on it yet people will still say why didnt you just buy a 200sx or Skyline if RWD is that important?

Nick Mann
20-01-2010, 10:49 PM
Aside from the point of view that this could be a lot of money to spend for little reward, could we try and keep this thread somewhere near the original topic, please?

Thanks all.

I am borrowing Nevs mower for a minute or three...

mesobitchy
20-01-2010, 10:50 PM
thank you nick!

this thread was taken way off topic!

Nick Mann
20-01-2010, 10:55 PM
Mower handed back to Elnev.

Please continue. Please try to keep it on topic!

miller
20-01-2010, 10:59 PM
Aside from the point of view that this could be a lot of money to spend for little reward, could we try and keep this thread somewhere near the original topic, please?

Nick, its more the absurdness that Maz actually tries to make us believe this will actually make the project flor which is galling for all of us to take. Especially when input and information that she doesnt want to hear is being slung back at the original poster.

Hence the degeneration.

Now back on topic of RWD a galant in your garage/whip


:beerchug:

/Welcome

mesobitchy
20-01-2010, 11:01 PM
....
RWD is something i wont mind, but it is also something that can wait.
the more important question about the engine and its parts was thankfully answered by brad.
and if anyone has more info along the lines as to what he has said then it is wecomed.

Bat
21-01-2010, 11:48 PM
Hi,
Good to know that the internals can take more power. N2O or as daft as it sounds LPG could be the answer here :)
Nos ... I don't need to explain the performance advantages of that surely?
LPG ... Equivalent octane of 116 :d All you need is more advance via a remap or other ECU. I'm hoping to go down this route. I know they just advance the timing by 6 degrees on Efi Range Rovers. Oh and it's 51p a litre!
Cheers,
Gavin :)

Johnny_Cashed
21-01-2010, 11:54 PM
Higher octane but less energy for an equivalent amount. I read liquid phase injection can potentially increase power but has not been successful so far.

Turbo_Steve
22-01-2010, 01:29 AM
Indeed: the lower calorific value means that the increased timing is only reallly getting you back the power you lose.