decided yesterday the smoke on over run i'm getting with my saph is completely letting the car down so in the near future i'm taking the head off to do some reconditioning work.

my question is this - what shall i do while it's off? been reading up here and there and general opinion seems to be the bottom end is perfectly happy running up to 400bhp on stock internals? so providing i don't find anything nasty when i take the head off i'm planning to leave the bottom end alone, it's only done 70k so surely shouldn't be anything horrific happening in there?

it's currently running stage 3, T35, greens, 3 bar, RS500 intercooler grp A coil etc and pushing out 327bhp when it was mapped and around 280lb/ft of torque if i remember rightly.

ideally i want to aim at 350bhp and torque as close to that as possible. am i being realistic or pi$$ing in the wind without spending mega money? i'd have thought i'm already on a good starting block having the stage 3 so i've got a shopping list that so far looks a bit like:

head - mild port and polish just to clean things up and get the gasses flowing nicely.

cams - not sure where to go with these? tempted to go with a bd10 inlet and leave the exhaust standard to avoid making it any more laggy but i'm completely open to opinions here as i'm only going on what i've read. also fit vernier pulleys for that bit extra adjustment.

fuel pump - looking at getting a 044 pump to ensure it doesn't start lacking fuel supply and put paid to my hard work!

am i aiming in the right directions here? any input very gratefully recieved.

 

Ay up john...for 350bhp you'll be fine with a standard head and cams imo. Just a set of greys and a remap should see you right on a solid bottom end and a decent fuel pump (no forgetting decent wiring to said pump also) Smoke on the over run tho...what you thinking, worn guide's? Only ask because it could possibly be worn oil control rings also mate.

 

ay up mate! yeah thinking along the lines of guides but the rings are nagging away in the back of my mind so might just as well pull the whole lot apart really hadn't i! if i go for greys won't i end up getting probs with bore wash and massive over fueling? i don't always drive it foot to the floor so don't want to go swapping the blue smoke for grey/black smoke. lol

 

go for a more modern siemens injector then? Altho from what I gather tuners have started getting greys to fuel better recently off boost also. Speak to your tuner in that respect.
On the rebuild front I'd do the lot in one go mate, have the head rebuilt new guides etc and then freshen the bottom end up...its all done then so no worries

 

what gains do you think i'd see from going for some cams and a little headwork etc? i'm only planning on having this thing apart once so might as well do the best i can from the off. if it means it being off road next year so i can finance it all then so be it, at least when it's back together it'll be done right.

how much do you charge for consultation when i start panicing that i've done it all wrong? lol.

 

Standard bottom end can take some decent power if its in good nick, same with the cams.

I had my head ported and polished with 3 angle valve seats and with standard cams, T38 turbo, grey injectors, group A f/pump and a few other little bits and bobs and it made really good power.

If u didnt want to run greys then the siemens injectors are another option.

 

IMO i wouldnt change anything. Standard head, standard cams, standard bottom end

are you running a 200 or 205 block? if you want more power later on maybe long stud the block

if you're pulling the head off you may as well do the bottom end; that way you know it will be OK

head wise; i would just to the guides and seals and give it a general clean up. Stick it back on with a grp a head gasket

injector wise go with a set of siemens Blacks, they come in commonly 55lb, 72lb or 83lb size - i run a stage 3 2wd with 55lb injectors. they are a newer injector which are less aggresive & have a better spary pattern

 

yeh good advice, head work at this level really does have many advantages, sure cams are handy but pricey and at this level not really essential. Some port and polishing is usually a nice way to go and just rebuild the head. No need to really go to nuts on the head unless you are planning to do other things. Why have a nice freeflowing head if you have a restrictive inlet plenum and exhaust manifold?

The beauty with the cossys is that you can realisticly aim anywhere up to 400 with pretty much a standard engine, just changing the littlebits around it. Injectors,decent turbo blah blah. Make sure you slap a decent head gasket on there and maybe even long stud it for extra safety. U cant go wrong here.

 

I had head work done to my old one. I wont wait a single day to rip the head off and send for a job if/when I get a new one.

Send it to a specialist that uses a gas bench so you get everything nice and matched, do ports both sides, 3-angle cut seats and port and match the intake to the intake ports.
It was night and day on my car. Same setup gave 17bhp on a standard engine before/after, tested on same bench.

Compliment it with a BD14 on the inlet and adjustable pulleys, the standard exhaust cam is really good enough for 400bhp.
If you got a 4x4, bin the exhaust manifold. The 2wd flows enough for A LOT of power, so the restrictions on that side is going to be the turbine housing.

Don't be disappointed if you find your block to be ready for an overhaul with wear grooves in the top part of the cylinder, and oval dia measurments. 70k with stage 3 for how long? is ready for a recon.

At least change the bearings and oil pump in the bottom when you have it open if the bore's are OK.

edited to add, I think all this is a waste of money if you don't spank up the money to get it livemapped. We don't have that option here in Norway, but I'd give someone's arm for the possibuility.

 

Just a note to add to RSCosworth's reply, if you plan on having a BD14 inlet cam (tad ott for the level you want in my opinon personaly) then you'll have to at least have the crowns of your pistons modded to suit the extra lift.

 

speak to stu at msd,the only way i ran greys was on his chip and no borewash evident when we removed head in march