E30 Zone

Right well I'm going to go down the road of a twin turbo setup because its easier than a single or for what little research there is on this. What sort of sizes of turbo do you recon I could go for? T3 maybe?
I don't want to go too big and go unreliable?

Just brainstorming at the minute, gathering info and parts for when I start it.

Sounds interesting Ben, is that one turbo for each bank? Often wondered what the benefit of twin turbo's was on a straight 6 (i.e one turbo for 1-3 and one for 4-6) rather than one bigger turbo for the 6 cylinders. For example the RB26.

Yes Andy that's what I was aiming for, it's just makes it simpler when piping the exhaust sides of things. If I had a single turbo for both banks then I would have to find a way to take a 3" pipe round from the other bank to join the turbo if that makes sense?

Yep totally, that may be a struggle to fit into an E30 bay! Will be awesome when its done

I'm hoping so, I really need to brush up on my turbo knollage though when gathering the relevant material to start the project.
Size of turbos, headgasket thickness if I need to change the pistons, compression that needs to be achieved ect?

http://www.speedhunters.com/2013/06/not ... apped-s14/

maybe worth a look

That's a bloody good read and food for thought thank you dude, might of found somewhere I can pick up a set of metal head gaskets too

Right abit of a update,

i get bored easily so im going to go ahead with this.
iv brought 2 garrett T25g turbos that im currently rebuilding to start with. once they are ready then i shall pull the M60 and start the manifolds and downpipes which im not looking forward to!
if anyone has put a M60 in a E30 then you will know the headache that comes with the manifolds let alone adding 2 turbos.


iv found a good candidate for a intercooler which incorporates both turbos.
http://www.ebay.co.uk/itm/350521981233? ... 1438.l2649

im trying to source a set of Copperring head gaskets which are in the UK and i shall be bolting the heads down with 2 sets of M50 ARP head bolts.

i shall try and update as soon as i can with plenty of pics

An S62 engine, but nevertheless, hopefully a little inspiration.



Some more here: http://forums.finalgear.com/general-aut ... are-31095/

Cheers. Dave.

That's a good bit of inspiration thanks Dave

Iv finally found a company that will sort me out a set of MLS head gaskets, I just need to work out the thickness which I'm struggling with.
Does anyone know the formula to work out the compression ratio needed for a low - medium boost setup with standard pistons?

I think the bently arnage used a twin turbo m62b44. Maybe you could copy some of the specs?

Did they? Holy hell I don't know that!
I'll have a look on the interweb now for details.

Thanks
Ben

Jon_Bmw wrote:I think the bently arnage used a twin turbo m62b44. Maybe you could copy some of the specs?

Yep - it was a Cosworth project done whilst I was working there...

We used an E39 5 series as a mule car - M suspension, a single tail pipe and a 518 badge just for a laugh. Awesome car that unfortunately got rolled up into a ball of scrap at Millbrook on the high speed bowl.

The specs have probably been lost as Cosworth as it split and became Cosworth Racing and Mahle - worth a google search at least?? It was a long time ago so struggling to remember the specs - T3s sound about right for the flow of each bank - about 0.9 bar boost at 9:1 compression ratio. It was running the latest (at the time) Bosch engine management, some package restricted exhaust manifolds, twin intercoolers, large (3") down pipes to stop turbine and compressor stall and a slightly larger standard layout exhaust. Standard cams as well as I recall but I could be wrong.

Hope that helps...

cool beans ill have a little search on the mighty Google but i recon my chances are quite slim of finding anything on it........ but you never know.
i pulled the M60 back out today so ill start a new build thread, iv managed to find a set of MLS head gaskets as well woop wool. only problem is they are in the US

would S62 head gaskets fit a M60 by any chance?

Doubtful but I'm no expert - I bought an MLS gasket for my S14 from the states, good price even with the duty at this end. As I said above, aim for about 9:1 compression and you will have a good compromise between boost you can run and off boost response but of course it depends on what you want to do with it....! First thing we did with escort cosworths to get them to go well was drop the compression down to 7:1 and crank the boost up to 3 bar...

Well all in all, I'm after everyone's goal of reliability vs power.
Lowering the compression sounds like a good move and pushing the boost alittle more. I don't want to change cams or pistons yet though.
I'll be having 2 rebuilt t25/28r either side so I'm hoping that will rule out lag.
If not I'll move upto the T3 and push the boost abit for more torque.

My only question is, where would I take the oil flow and return to the turbos and a water feed as well?

Im keen to see how your progress goes as im doing the same thing

For sure you are going to be asking yourself a lot of questions whilst you do this - all part of the fun!

Just a few thoughts from the top of my head:

Looking at Wikipedia, your CR will be too high for both b30 and b40 variants so you will need to lower it.

A good benchmark for power is 100hp/litre for reliability and a good torque spread - any e30 with 300 or more horsepower is going to pick up its skirts well!

The turbos you have sound ok to me but you need to dig a little deeper - do you know what vehicle they came off?

Boost isn't everything - you will gain oodles of power from well optimised exhausts and intakes (we got 50hp more on 0.25 bar LESS boost on a Bentley Continental R just by sorting out the tragic intake on the base car). Have a good think about how to smoothly get air into the turbo and through the intercoolers - any restrictions here really hurt you later on.

Aim for 3" pipes out of the turbine on the exhaust side - it helps a lot and reduces lag.

If you have standard pistons, limit your boost to less than 1 bar, as low as you can - remember, it's not just about boost but AIRFLOW...

Don't worry about port shapes or anything else - you are forcing air into the engine - look at that later if you wish. Likewise cams - leave them standard.

Lag is a fact of life - it's how well it is masked that's the trick - either by turbos a touch too small (a great example is the Audi S4 - turbos too small for good response and they over speed on a standard car - an engineering compromise!) or too big. Masking can be done with mild cams, higher CR, spark advance off boost, good airflow management of the exhaust side and intake.

Oil feed needs to be from your main gallery from block or head. -4 AN should be ok. You may need a restrictor, but I doubt it.

Your drain needs to flow downhill - no U bends at all and at least -10 size returning to the sump above the oil level but away from major windage points - I would look at what other folks have learnt.

In terms of water supply - anywhere that gets flow from first start is just fine - most use the heater circuit and that is a good starting point.

There's a wealth of knowledge out there - google and this forum are your friends!!

Well holy hell thank you mikey boy you legend, if that's not food for thought then nothing is.

How would I work out what CR would be a suitable lowered level and then convert that into head gasket thickness?

Also the 2 turbos I have rebuilt are T25/28r from a couple of 200sx.

Next thing is to figure out where I could tap into the oil feed via the block or head (Google)

Need to find out what size injectors are standard on the M60 and then see what they top out at? Possibly could go for a set from a S62 maybe or a cheaper substitute.

Management? Not sure yet, was going to leave that until a later stage and hopefully something comes my way cheap

I will start the build thread with mega loads of pics once I start this week hopefully

Good man - we like lots of pics!! Are you doing a b30 or b40 with twin turbos? In all the engines I developed, there is nothing quite like a turboed V8 as it has the best of everything - great sound, monster torque and (relatively) easy to package..

In terms of your CR, lowering it with standard pistons will compromise things like squish and the amount of boost you can use (as the piston top thickness is greater for turbos to cope with the (sometimes) increased cylinder pressure and (definitely) increased heat) but as a way to get started, it's not fundamentally flawed.

For your calculations, have a look here as a starting point:

http://www.gtsparkplugs.com/CompRatioCalc.html

There are similar online tools for injector sizing as well - all related to power output and remember to oversize by at least 10% to compensate for things like resolution whilst mapping and fouling over time.

Any standalone has it's pluses and minuses - that's a debate on its own!!

Most of all, good luck and enjoy it - building should be as much fun as using...

And don't hold me to this, but I reckon for 0.9 bar boost, you should aim for an 8.8:1 compression ratio to get the best of everything...

Wicked bit of extra info there mikey boy,
After popping the m60 in the e30 I realised that I had more fun building it than I did driving it so here I am again for a further stage 2 project.
Iv never ventured into force induction before so it's all new and exciting ”¦
Although after reading out loud about new low comp pistons my wallet has legged it and I can't find it for love nor money.

It's the b40 I have so a good base for forced induction plus the added bonus of the M60 twin timing chain.

There's lots of research I still need to grasp and I'll probably be single by the end of this but it will be worth it.

Key components

Oil lines
Water lines
Boost pipes
Vacuum lines
Manifold magic
Exhaust trickery
Management
Injectors
Head gasket
ARP head studs/bolts
Convert the rear vacuum plate to a sealed blank to accommodate positive intake pressures (easy)

”¦ bolt the somebitch up