Sierrasideways

iTrader: (1)

Hoi hoi everyone,

Upon reading many,many threads on here with vast varying opinions....I would like to know what power I should expect with my new spec.....

Engine is being put together as we speak...

*** I want 400/400 ***....not sure if I can make it but maybe you experts can help me out if I'm doing something incorrect

Cheers

Spec for my Sierra Cosworth 2WD:

200 block
Accralite 92mm pistons with valve cut-outs
Standard compression ratio 8:1
4X4 head
Standard cams ( although I have a BD10 inlet cam if I need it )
GRP A head gasket
GRP A cone air filter
GRP A coil
Airtec RS500 style Top feed 100mm core intercooler
Airtec radiator
T34/0.63 turbo
-31 actuator
Oil breather kit
3 bar MAP sensor - ( 5 bar MAP on the way....not sure what to do with this as I'm getting mixed reviews i.e. hardly any being used nowadays, help!!...Is it a better choice with lower resolution??? I just don't know )
L8 ECU ( will be getting the car remapped as it is being rebuilt fully )....although I have a 380+ MSD chip already ( unused as of yet! )
Black Siemens 55lbs injectors
ARP stud and nut kit
All new hoses, bolts, clips, crank bearings, gaskets, seals etc.....

I probably forgot some things agreed......

Do you think it's possible to make the 400/400?????

Thanks in advance.....ALL suggestions welcome

Philip.

Billy_RS

iTrader: (5)

Your along the lines of my spec.

I don't know the exact figures but I'm guessing around the 360-380bhp area.

Sierrasideways

iTrader: (1)

Cheers Billy.....

A quick q, would u think anti-lag and launch control would be a good buy?

I think it would take all the fun out of the BANG of boost

Possibly might upgrade....

Philip.

KSA-Cossie

iTrader: (4)

If you ran a heap of boost, you'd get the hp but doubt you'd get the torque tbh.
I've got ALS & LC and love them lol

Billy_RS

iTrader: (5)

Anti lag will give you a lot more bangs tbh! Lol

Sierrasideways

iTrader: (1)

Hmmm, I'll have to think about that one Billy!!

@KSA...how can I make 400/400 so because seeing other guys Cossies on this, they have made these figures???

I know saying it and actually seeing it are 2 different things! lol

How can I make 400/400?

Cheers,

Philip.

LHD220Turbo

iTrader: (4)

you'll make 400/400 depending on which rolling road you use

dont get too caught up with wanting 400/400 - its just numbers. A t34.63 makes for a very quick road car, 2.2 bar of booat should see 400hp, but dont ring the turbo's neck otherwise you'll be changing it

Sierrasideways

iTrader: (1)

Thanks LHD.

We're not exactly spoilt for choice here in Ireland for rolling roads lol!!

Ideally before Ford Fair I'll get it live mapped across the water.

I'm not number chasing, essentially I just want a reliable 400/400. I know the turbo is on the hairy edge at this power and boost. Don't really want to be changing it every 12-18 months

The bhp I'm not all that worried about, it's really the pulling power ft/lb I want.....

A couple of ideas would be great!

Staffi

iTrader: (1)

Ditch the T34 and buy a GT3071 or T38 and run less boost hence lengthen Turbo life

Sierrasideways

iTrader: (1)

Hi Staffi,

I just bought all these bits so don't really have the funds for MORE new parts aargh!!!

Will keep it in mind and start saving the shillings again

Cheers mate.

Philip.

KSA-Cossie

iTrader: (4)

You could get CR Turbos to turn your T34 into a T38

Sierrasideways

iTrader: (1)

The research begins lol

Working nightshift so I've all the time in the world

Cheers KSA

KSA-Cossie

iTrader: (4)

No problem mate, do it once and do it right

Sierrasideways

iTrader: (1)

Duly noted

I wanna be in the club!!!!!!!!!!!!!

jamie's

380bhp, could push 400bhp if you ring the neck of the turbo
as said go bigger turbo for reliability
also why valve cut out with standard cams?
and is your 8-1 comp ratio before the pistons where machined for valve cut outs?
if so then your no longer on 8-1,
torque wont do 400 with the spec
best mod is bigger turbo, better inlet cam and decent live map
that should give you your 400bhp and near on your 400lb/ft
but as said, dont chase numbers, that set up will give a very fast road car(unless your ROD)

Rod-Tarry

Rod has not had a car on the road for a very long time mate so ignore any references to my car that was back in the day. Enjoy your car & dont chase numbers cos someone will always have a bigger number. I make do with 200bhp these days & its more than fast enough.

DAN400

iTrader: (3)

you ll must likely have to run the car on unleaded, being in the south,
that will not help your cause.

Sierrasideways

iTrader: (1)

Cheers Jamie...for now I'll stay with the T34 as my bank balance has a hold on me Valve cut-outs were made because I want to future proof the car for bigger cams when I head for the 500+ mark....just thought it would be better doing it sooner rather than later. You know more than me when it comes to compression ratios...I was advised stay standard for now, that's why... Thanks for the tips, all good to know.

Rod, thanks for the reply, a pleasure
Agreed, number chasing is irrelevant.....I would just like a reliable 400/400 and I think this will be more than enough on the tarmac. I don't like guessing games.....I kind of like to know exactly what I have if you know what I mean. I wouldn't enjoy it any more or less if it was 200bhp or 2000bhp....it's the knowing for sure that interests me

Hi Dan. You're right there.....not exactly a great choice down here.......I'll probably whack on some laughy gas to compensate

Cheers for the replies lads, when it is built, ran in, rolling roaded and mapped.....I'll have an update and some pictures.

Hope it'll be worth it

Cheers,

Philip.

Sierrasideways

iTrader: (1)

Hi Jamie's.

I have an update.

I have 92mm accralite pistons but NO valve cut-outs. I asked for valve cut-outs but they sent them with NO cut-outs and they are now installed in my engine....

I was told I can put in a crazy cam later on if I wish because the pistons are sitting lower than normal so will have enough clearance for the bigger cam.....again, I'm not a mechanic so I don't know if this is OK or not......is it?

I just don't want to rip the f-ing things out again 1 or 2 years down the line.

Any help would be appreciated......basically my question is are these 92mm accralite pistons with NO valve cut-outs, good enough for 500+bhp?

Cheers.

Philip.

nixon_2wd

That depends on the clearance. But if youre at 8:1 with those pistons then most likely you wont be able to fit bigger cams (than BD14) as they will hit. = no 500hp.

Sierrasideways

iTrader: (1)

Hi Nixon_2wd...thanks for the reply. I've spoken with a few people today about this and I am getting ( as per f-ing usual ) a mixed bag of responses.

I was 100% assured that the clearance from the pistons is enough to install a big cam at a later date......

The new pistons are flat top and 4MM DOWN from the bore top. I was told this is the same as a normal full size piston at the bore top with valve cut-outs machined into them. Essentially the flat top of the piston is the same height as the BOTTOM of a valve cut-out so there shouldn't be an issue. This is the argument FOR.

The argument AGAINST is simply agreeing with yourself, saying that the pistons are too high for bigger cam clearance.

I hope I described it clearly enough for you.

Can you shed any light on the subject now with this extra information.......or can anybody???

I want to future proof the car for 500+bhp so hope I won't have to strip the bi-otch again.

All suggestions and/or advice is welcome.

Cheers lads

Philip

Sierrasideways

iTrader: (1)

The new pistons are flat top and 4MM DOWN from the bore top. I was told this is the same as a normal full size piston at the bore top with valve cut-outs machined into them. Essentially the flat top of the piston is the same height as the BOTTOM of a valve cut-out so there shouldn't be an issue. This is the argument FOR.

The argument AGAINST is simply agreeing with yourself, saying that the pistons are too high for bigger cam clearance.

Anybody got an answer to this one please...?

Has anyone seen a similar setup before?

Stu @ M Developments

iTrader: (12)

Why have you fitted pistons with no squish area mate? That's not a good thing to do at all!

You could have achieved close to your goal with standard pistons, a sensible inlet cam, good intercooler, your L8 ECU and 3 bar then a morning drinking coffee in my dyno waiting area while we map your car live on my dyno with lots of boost.

Your dramatically lowered compression ratio and removal of squish area has pretty much gone against everything your saying you wanted to achieve.

Sierrasideways

iTrader: (1)

I hear u Stu...

I didn't know the pistons were set up this way until the thing was put together, nothing I could do then. Also not being a mechanic I didn't realise the implications that these pistons would have.

I bloody wanted accralite forged with cutouts for bigger cams down the line. Now I have what I said, pistons sitting lower than usual, supposed to be standard comp but obviously not.

I have one of your 380+ chips in the L8 and now I'm not so sure that the pistons will cope with the boost etc.

I was 100% assured that it will work but listening to yourself and everyone else on here, it won't.

I'm once again confused as to where to go from here.

The engine is together and running sweet. 1000 mile burnin complete.

Was going to set it up for boost next week.

If I'm doing wrong or right I don't know, I'll just have to wait and see.

Ideally I want to spend a morning drinking coffee over with you guys before Ford Fair...not sure if you'd want to take on doing this mapping now with the info above......

Can it ever be right with these faacking pistons???

I guess if I hear a BANG, I'll know.

Thanks for the reply anyways, will post again with results ( if any )

Cheers,

Philip.

dazzle740

iTrader: (1)

I would suggest getting it set up with reduced boost and enjoy with a safe 350ish bhp for now (forget your 400/400 and certainly 500bhp) and build your funds until you can afford to remove the lump and get it rebuilt with the correct dish, height and cut outs for your future plans.
As you will kill your T34 if you try to achieve 400.
Get the inlet cam swapped for the BD10 and maybe fit W/S kit and get it mapped and you'll have a very potent toy in your hands.

Stu @ M Developments

iTrader: (12)

Morning mate, I wouldn't worry about boost killing it because of the pistons height mate, I doubt that will be an issue unless the pistons were very thin before they skimmed 4+mm off them. A quick call to accrue should answer that one. Integrity wise its probably absolutely fine. What you end up with when you reduce compression in this way is an engine that just isn't as efficient as it should be, and they can be a bit tricky to get absolutely right as they tend to require a bit different fueling when the squish band has been removed as the charge behaves a little different as the piston approaches TDC. (Oversimplified)

Detonation can be a bigger issue when you reach optimum ignition angle as the lack of squish band can cause some odd mixture pockets around the cylinder, but the bottom line is, as long as its mapped live none if the above should be of any real consequence to longevity as it should all be just fine. It will just be a bit down on torque and feel a little less "punchy" than she would have where she still 8.0:1.

BIL N KEL

My old engine had skimmed standard pistons and joe @ hart power said it was a very low comp ratio when he replaced the head gasket. When my new engine was built by joe with proper cosworth racing forged pistons there was so much more torque in the low-mid range it was in believable.

jamie's

4mm seems a lot to take off, no way thats still 8.0-1
dont know how low that is(anybody got any ideas?)
i'd imagine it will be pretty gutless off boost and laggy
seems a funny way to spec an engine, or 1 i've never witnessed before so i dont know why its been done that way

Bart

I assume because they are flat top pistons they can be 8-1c/r. They dont have a bowl like the original pistons.

DAN400

iTrader: (3)

when I first got my car ,7/8 years ago it had extra low comp accralite pistons in it,
they sat down the bore about 4 or 5 mm too
I think comp ratio was something silly like 6.8:1
now that's proper low comp lol
engine went fine but was very laggy

Sierrasideways

iTrader: (1)

Morning Stu.

Good clear explanation, much appreciated. I'm happy with what you say as now it should be ok but obviously not as good as having the proper pistons i.e. It will just be a bit down on torque and feel a little less "punchy" than she would have where she still 8.0:1.

Cheers mate

Below Bart makes the point:

This is what I was saying earlier (but wasn't clear enough to accentuate the fact that there was NO bowl cut out):

The new pistons are flat top and 4MM DOWN from the bore top. I was told this is the same as a normal full size piston at the bore top with valve cut-outs machined into them. Essentially the flat top of the piston is the same height as the BOTTOM of a valve cut-out so there shouldn't be an issue. This is the argument FOR.

I was told that because unlike the ''normal'' pistons which HAVE a bowl and valve cutouts in them, my new pistons will sit a little lower but have more meat in them i.e. NO bowl or valve cutouts, so in theory it is essentially the same...so I should have 8:1 compression.

I know it's a weird strange one buy hey, this kind of stuff just happens I guess

Would you think it's a good idea to do a compression test just to verify correct compression before setting up the boost on the rolling road..?

Or am I just clutching at straws because if I find out the compression is not correct for my chip, 8:1 compression, I'm gonna have to pull the bloody thing off anyway. Probably I should just plough on and set the boost to a safe level which is what I intended to do anyway.

gents

Philip.

Sierrasideways

iTrader: (1)

p.s. Changing the oil last night and the faaaaaacking sump plug threads came out with the sump plug

I love this car, wanted one for as long as I remember, but there have been more problems with it than an STD clinic full of hookers.

The labour of love continues

DAN400

iTrader: (3)

the joys mate,
you could fit a helicoil to it but Id take of and get it fixed right,
I fitted a time-sert to mine as I always pissed out through the helicoil that someone had fitted at some stage

Stu @ M Developments

iTrader: (12)

How big do they think the valve cutouts are?!?!
This is one I built myself, the cutouts are big enough for a BD16+ and once CC'd this worked out at 7.7:1.
(Which is the lowest I go with a YB ever.)






Note the pistons protrude ABOVE the block as standard to give the 8.0:1 CR and when decompressing I keep that piston height as its important to the engines efficiency that the mixture is squeezed inwards as the piston climbs to TDC. (That's one of the reasons that spark plug is in the middle... ).


Compression test will not tell you the Compression "Ratio"
To do that it needs to be assembled and filled with fluid, like this.



Once you know how many CC's of fluid the combustion chamber holds, you can work out the CC from Bore and stroke.
That was your engine builders job and you should be given all this info with your engine really. (We supply all that data plus a CD of pictures from the build)


The compression ratio is definitely not right for your chip mate, but its safely low instead of dangerously high.
The only long term worry is EGT (Due to lack of spark lead)as opposed to detonation so just get it live mapped and then you can stop worrying about it.

Sierrasideways

iTrader: (1)

Hi Stu,

That is now crystal clear to me. Thanks for the effort and detailed description.

As you can tell, I am a tad ( ) nervous about the Goddamn thing blowing up and going boom.

I know what I'll be doing and I know where I'll be going in the future

Thanks a million mate, seriously.

Will post revelations when I have them...next week all going well.

Philip

Stu @ M Developments

iTrader: (12)

Your welcome mate, always happy to help when I have a bit of spare time. Not been round here much since I started this damn dyno cell build as its too all my spare time, money, patience and, sadly, enthusiasm.

Don't worry too much about it. Excessively low compression isn't going to blow it up, just means your having more boost. LOL

Sierrasideways

iTrader: (1)

Hahaha great stuff

I've a feeling your enthusiasm will never give in Stu.....no matter what you say lol

I'm looking forward to the unwanted low compression, high lag, not enough boost, wrong petrol, pulling to the left a little, dodgy connections, rats nest of wiring and just the sheer thrill of wondering what was that squeek, bang, rattle, fizz, pop and whistle when I'm driving.

And you're wondering about your enthusiasm??? HAHA

jamie's

thats just an average day out in a cossy to be honest
as stu said already, a comp test wont give anythng away but theres no way in hell its still 8.0-1
get it to stu for a live map and it'll transform the way the car drives

Cilly-jey

Book a ferry to heysham then pop mo the m6-m55 chill at msd for the morning then off you pop to ford fair for the Sunday. Job done and no more worry

Sierrasideways

iTrader: (1)

An update at last!

Left the boost at 'safe' 1.8bar and it made 325bhp and 385ft/lb.

Not sure how accurate the dyno is.......car does go well though.

Weird thing is it seems to misfire in 3rd gear only? Researching on here and could be numerous things like plugs, leads, coil etc etc etc.

Proper map in January 2014 for fucking sure.......

It's this car

https://passionford.com/forum/restor...-cosworth.html

Thanks for all the replies.

Cheers,

Philip.