has anyone tried sourcing or fitting a MIVEC or DOHC top end to their 380 engine 6G75??

The 380 shared the same engine as the current AUS pajero and they are running SOHC MIVEC 3.8s (I think)

Or is it a too much, too hard basket jobbie??

This is the cloest I know of...
Pajero 6G74 with the 3.8L SOHC MIVEC heads turbocharged... (In a 3000GT)
http://www.3si.org/forum/f1/mivec-build-435608/
(Will have to join....)

Yeah I have looked all over the Interwebz to see if anyone has done one ETC and looks like plenty of 74s bored out but no 75s with new tops

Why are you wanting to go DOHC or MIVEC? The SOHC head flows very well (http://www.aussiemagna.com/forums/showthread.php?t=67778&page=2) and soon there should be good road cams available. Graham Bell has made 4 master cams (inlet & ex lobe for front bank and inlet & ex lobe for rear bank) and is currently due back in Aust any day with his first pair of cams for testing and durability trials.

Cheers,
Alan

I think most people's cars are too new to worry about spending a lot on an engine upgrade like that. Talk to us in 10 years time, hopefully the Paj will have an even better and compatible V6 in it.

I am looking for economy
been a Toyota Phanboi the VVTi was always about economy rather than performance
And my belief (I could be wrong) that DOHC or Mivec will deliver small gains in power but good gains in economy

I will put it on my wish list

Let us know how you go. I'm happy with the economy of my 380 for the size of the car.

Unfortunately my wife has become a HOON in the GT and I am getting 15-16l/100km round town

If your wife is hooning about it doesn't matter what motor you put in there it's still going to using loads of juice, plus I think the price of the engine+putting it in+tuning is going to cost you A LOT.

Probably cheaper to buy her a small 4cyl run about.

I am looking for economy
been a Toyota Phanboi the VVTi was always about economy rather than performance
And my belief (I could be wrong) that DOHC or Mivec will deliver small gains in power but good gains in economy

I will put it on my wish list

MIVEC is for performance. The extra cam lobes give a broader power spread. The short duration low lift lobes control the valves at lower rpm and then as rpm rises the rockers swap to the bigger lobes. DOHC usually adds weight, friction and complexity so generally increases fuel consumption.

Graham is soon going to check if the stock 380 cams can be advanced without valves hitting the pistons. Most likely they can be. That will give a good power increase and improve fuel economy. The tiddly cam fitted to the USA model Galant is milder than the Ralliart used in the Aust 380 so may improve economy but will reduce power.

Cheers,
Alan

Cool thanks

I have my Corolla which does not have a baby seat in it ATM

Tuesday will be D-Day I think

just have to get my MTB out of the back of it and put in a second seat

Alan thanks for enlightening me cause I have NFI with mechanicals apart from the basics
There is no way I want reduction in power for the sake of economy though I want both LOL

I apprieciate all the replies and not getting flamed for being a noob LOL

MIVEC is for performance. The extra cam lobes give a broader power spread. The short duration low lift lobes control the valves at lower rpm and then as rpm rises the rockers swap to the bigger lobes. DOHC usually adds weight, friction and complexity so generally increases fuel consumption.

Graham is soon going to check if the stock 380 cams can be advanced without valves hitting the pistons. Most likely they can be. That will give a good power increase and improve fuel economy. The tiddly cam fitted to the USA model Galant is milder than the Ralliart used in the Aust 380 so may improve economy but will reduce power.

Cheers,
Alan

It does add more parts, Weight, hardly any and the fuel consumption is usually better as the motor is making the most of the fuel going in. Local DOHC wagon near me gets thrashed every week and still gets 10L/100k's (1500kg car)
Basic numbers says it all for me
SOHC V6 12v 3L 120kw
DOHC V6 24v 3L 165kw
DOHC V6 24v 3.5L 196kw

been a Toyota Phanboi the VVTi was always about economy rather than performance
In my dad's Presara you can definitely feel the power increase around 4,000 rpm when VVTi kicks in. I'm sure other Toyota VVTi setups are similar to this.

;1067915']It does add more parts, Weight, hardly any and the fuel consumption is usually better as the motor is making the most of the fuel going in. Local DOHC wagon near me gets thrashed every week and still gets 10L/100k's (1500kg car)
Basic numbers says it all for me
SOHC V6 12v 3L 120kw
DOHC V6 24v 3L 165kw
DOHC V6 24v 3.5L 196kw

10.8L/100km last and only time i took the calculator out to check... but usually about there... I don't trash it every week ffs..... :ninja:

In my dad's Presara you can definitely feel the power increase around 4,000 rpm when VVTi kicks in. I'm sure other Toyota VVTi setups are similar to this.

You do get a surge almost like OLDSKOOL turbo LAG

the Aurion has a different more advance VVTi setup to the 4 cylinders (Due to F1 technology?? could just be marketing)

Too bad the dynamics in the Aurion is like sailing a boat through the desert but Toyota's loss is Mitsubishi's Gain:woot:

;1067915']It does add more parts, Weight, hardly any and the fuel consumption is usually better as the motor is making the most of the fuel going in. Local DOHC wagon near me gets thrashed every week and still gets 10L/100k's (1500kg car)
Basic numbers says it all for me
SOHC V6 12v 3L 120kw
DOHC V6 24v 3L 165kw
DOHC V6 24v 3.5L 196kw

How does DOHC make better use of the fuel going in? Fuel burn is all about fuel atomisation quality, combustion chamber design and piston crown shape, plus correct spark timing.

The DOHC power numbers you quote are higher because the cams are longer duration and comp ratio higher. The SOHC engines could easily make the same sort of kW. The team got 200kW from the SOHC during Ralliart Magna development.

In road engines main advantage with DOHC is the ability to change cam phasing and adv/retard so a bigger cam can be positioned to idle smoothly, pass emissions requirements more easily and not lose so much low speed torque.

Cheers,
Alan

How does DOHC make better use of the fuel going in? Fuel burn is all about fuel atomisation quality, combustion chamber design and piston crown shape, plus correct spark timing.

The DOHC power numbers you quote are higher because the cams are longer duration and comp ratio higher. The SOHC engines could easily make the same sort of kW. The team got 200kW from the SOHC during Ralliart Magna development.

In road engines main advantage with DOHC is the ability to change cam phasing and adv/retard so a bigger cam can be positioned to idle smoothly, pass emissions requirements more easily and not lose so much low speed torque.

Cheers,
Alan

I know 1/10987668th of what you know so take it easy on me but having the seperate cams for intake and exhaust are surely better then having the one cam do two things.
The DOHC Motors are all 10:1 and some of the 3L 72' 12v's do come in 9:1 in the US but all around the same CR
And I'm sure Mitsubishi already did this R&D but wonder why they TT'd the DOHC for the 3000GT and not the SOHC, although I've seen some damn impressive numbers from the 3L 12v 72 (turbo'd) I'm sure mitsu have a reason for not using them in an FI application..

I'm sure they did get 200kw from that motor, since they make 180 odd in the car im sure one of Steve knight's tunes would of bought it up over 200 no worries.

Personally I still think you should use the best building block you can get your hands on.

;1069008']I know 1/10987668th of what you know so take it easy on me but having the seperate cams for intake and exhaust are surely better then having the one cam do two things.
The DOHC Motors are all 10:1 and some of the 3L 72' 12v's do come in 9:1 in the US but all around the same CR
And I'm sure Mitsubishi already did this R&D but wonder why they TT'd the DOHC for the 3000GT and not the SOHC, although I've seen some damn impressive numbers from the 3L 12v 72 (turbo'd) I'm sure mitsu have a reason for not using them in an FI application..

I'm sure they did get 200kw from that motor, since they make 180 odd in the car im sure one of Steve knight's tunes would of bought it up over 200 no worries.

Personally I still think you should use the best building block you can get your hands on.

OK I'm not against the idea of DOHC. It certainly makes life a lot easier for tuners/developers when testing cams as you can easily change lobe separation angles and check the outcome very easily. With SOHC you have to grind a new cam to do the same thing.

However there is a lot more to engine efficiency than just the cam arrangement. 20 years ago we had to convert the Jag V12 Le Mans from SOHC 2 valve to DOHC 4 valve. The expectation was lots more HP and better fuel efficiency as the 2V was pretty ordinary. In reality the end result was 20HP more at top peak and a bit more mid-range but an engine that was 40lb heavier.

DOHC is good in high rpm situations as it calms valve-train harmonics, and the extra bearings stiffen the valve train. However for anything up to about 8,000rpm SOHC is fine. Most manufacturers going with DOHC have done so for marketing, and it helps with emissions being able to give more control to valve events.

I haven't seen any recent Mitsubishi DOHC heads so can't comment on the design. However I have seen the old DOHC 6G72 turbo and the newer Mitusbishi SOHC heads were a better design. The 380 6G75 are very good.

Cheers,
Alan

Weather or not they are "good" beats me but guys in the US are running 800HP through completely standard heads so they must be alright for something :P
Thanks for the writeup though was a good read

;1069638']Weather or not they are "good" beats me but guys in the US are running 800HP through completely standard heads so they must be alright for something :P
Thanks for the writeup though was a good read

Given enough boost and cam duration you can get big numbers out of any rubbishy head. Not saying the Mitsubishi DOHC is in that category though. I doubt the claim of 800HP on stock heads. Most likely got bigger better material valves/seats and at least some porting done.

When I refer to a head as being "good" that is relatively speaking. Meaning that it will give good HP and torque with a mild road cam, and return good fuel economy. To all intents the Chev LS1/LS2 in the Commodore isn't too bad but it needs stacks of cam duration and big valve lift to make the HP because of head limitations. If we ran the stock Chev cam in a Magna/380 we would see big HP too. In fact the cars would be just streetable, but a real hoot at track days. The 380 would probably be up around 230kW from 3.8 ltrs compared to 250kW or whatever from the original 5.7 ltr LS1.

Glad you enjoyed the read.

Cheers,
Alan

If we ran the stock Chev cam in a Magna/380 we would see big HP too. In fact the cars would be just streetable, but a real hoot at track days. The 380 would probably be up around 230kW from 3.8 ltrs compared to 250kW or whatever from the original 5.7 ltr LS1.


:woot:

Well, I'm game!
Shows what a tame cam the 380 got.

:woot:

Well, I'm game!
Shows what a tame cam the 380 got.

Richard, if your gonna play with your cams you better get those extractors on first :woot:

Everyones getting on the bandwagon, you'll have the lowest powered 380 around if you don't pull your finger out :rofleek:

:woot:

Well, I'm game!
Shows what a tame cam the 380 got.

Yes the Ralliart/380 cam is very very mild. The old "6" cam in the 163kw 3.5 ltr was 171 deg duration @ 0.050" and 9.05mm valve lift, the Ralliart/380 is 181 deg duration @ 0.050" and 9.8 mm valve lift, the cams Graham has just made overseas and returned to Aust with are 196 deg duration @ 0.050" and 10.9 mm valve lift. The LS1 is 206 deg duration @ 0.050" and 11.9 mm valve lift.

Cheers,
Alan

Richard, if your gonna play with your cams you better get those extractors on first :woot:

Everyones getting on the bandwagon, you'll have the lowest powered 380 around if you don't pull your finger out :rofleek:

Haha!

That's OK.

I was the first on here and I'm really happy a lot of ppl are now doing the same and appreciate the car. There is still a lot more to come, but we'll have to rely on Graham, Alan and Dave TJ to guide us further.

As far as my current output goes; it really feels well balanced with the chassis and braking. I wish Mitsu had released the car like it feels now. I'm quite content with it but a developed set of cams is too good to refuse.

Haha!

That's OK.

I was the first on here and I'm really happy a lot of ppl are now doing the same and appreciate the car. There is still a lot more to come, but we'll have to rely on Graham, Alan and Dave TJ to guide us further.

As far as my current output goes; it really feels well balanced with the chassis and braking. I wish Mitsu had released the car like it feels now. I'm quite content with it but a developed set of cams is too good to refuse.

So you think you might go that way huh? I think with a set of extractors Alan's estimate of 230kw would be spot on as mine was probably doing about 215kw before I put the blower on. If the 380 SF eventuates that could be some mean package. :badgrin:

Really been enjoying these posts and the forum in general,thanks guys.Wasn't going to touch the 380 really but can't help myself after all this reading.(once a fiddla always a fiddla!) Anyway, I've seen the dyno results on this forum but haven't seen any 0-100 times etc(sorry if I've missed them somewhere)Would be good to see what these gains have given you in real world performance.Thanks

380 SF

Please EXPLAIN??

380 SF

Please EXPLAIN??

380 Street Fighter manifold, go have a look in the Raptor Supercharger section. Tim has put up a new sticky ...... **STREETFIGHTER** FOR 380 - Tenative orders

thanks

I told ya I was a NOOB

Really been enjoying these posts and the forum in general,thanks guys.Wasn't going to touch the 380 really but can't help myself after all this reading.(once a fiddla always a fiddla!) Anyway, I've seen the dyno results on this forum but haven't seen any 0-100 times etc(sorry if I've missed them somewhere)Would be good to see what these gains have given you in real world performance.Thanks

For a road car 80 -120kph or 80 -130kph time is a lot more relevant, and as you are already rolling the times tend to be more accurate and consistent. If done in 3rd, 4th and 5th gear the times give a good idea of how well the engine hauls in the mid-range.

Cheers,
Alan

Hi Alan, yeah I agree.Getting these open wheel F.W.D cars of the mark quickly and consistently for 0-100 times can be tricky as I found out, an L.S.D would be nice.Unfortunately 90 is the fastest road close to me so doing 30+ over that is tempting fate alittle! I guess 0-100 and 400m times are the ones we've become most familiar with over the years when it comes to performance figures , as kids I remember thats all that mattered when arguing with a mate! Cheers. Mark