944 Turbo S Engine Rebuild Thread
- Thread starter Eldavo
- Start date
Probably a useable 450ish in a low stressed state and that will work for trackdays too. I can have switchable maps on the ECU so when it’s tuned and we can monitor everything I would like to see if we can break 500bhp though. The advantage to the 16v head is the hugely increased flow meaning I don’t have to put 23psi through it as I currently am in my 2.5 8v.
scam75
Well-known member
Sounds good, yeah the 16v head opens up a whole new world of possibilities. I think mines peaks about 21psi in 5th with the MBC and drops back and holds about 18psi. I think I'll wind that in a bit for my running in period.....[
]. I also don't imagine even my rebuilt K26/8 would have much more reliable puff than that anyway although I think I hit about 28psi when my wastegate diaphragm decided to let go, admittedly only for a very short period. Was quick right enough
Stuart
]. I also don't imagine even my rebuilt K26/8 would have much more reliable puff than that anyway although I think I hit about 28psi when my wastegate diaphragm decided to let go, admittedly only for a very short period. Was quick right enough Stuart
blade7
Well-known member
I wouldn't run more than 18 psi through the gears on a K26/8, and 16 psi continuously. Boost is addictive though, I kept adding more to my old Capri 2.8 injection until it got a bit noisy, and I reckon the rings had broken. And my Escort RS Turbo flew when I briefly ran 20+ psi.
Mines not a standard K26/8 though - I had it rebuilt and made hybrid by Turbo Dynamics. Just checked - it’s set at 21psi, 23psi produced no more power but intake temps started to rise on the dyno.
Should the intercooler get heat soaked on track then there is a table in VEMS that reduces boost based upon inlet temps going over a set threshold, also pulls injector timing based upon coolant temps too.
Should the intercooler get heat soaked on track then there is a table in VEMS that reduces boost based upon inlet temps going over a set threshold, also pulls injector timing based upon coolant temps too.
scam75
Well-known member
blade7 said:
Thanks Blade. With the MBC it peaks about 19psi in 3rd, 20 psi in 4th and 21psi in 5th, and drops off 2 or 3psi holding throttle. So it's in the sweet spot in 3rd but maybe a tad over in 4th/5th. I suppose an EBC is the answer but in all honesty the car sees very little WOT and I don't want to lose the 2 or 3 psi through 3rd just to make 5th peak at 18psi. Saying that, it probably won't make a massive difference and now the engine is rebuilt I'm sure it will be more efficient across the range so will probably dial it back a tad in the interests of longevity!
Out of interest I spoke to Lindsay a few years ago and they were confident that their chipset will fuel properly for 23/24psi using super unleaded. I suppose it's more the unnecessary load on the turbo and piston rings etc. that I need to consider.
Stuart
blade7
Well-known member
I'm guessing you're running at least 55lb injectors at that boost level? And Lindsey do make some pretty bold claims about some of their products. Flirting with high boost for a second through the gears, isn't the same as holding it in top gear IMO. Depends what the roads/enforcement are like where you live I suppose.
scam75
Well-known member
blade7 said:
No, I'm on cleaned standard injectors and the fueling is all good, low 11's AFR at peak boost (21 psi). I had 55lbs injectors for a bit and the car never ran right with my chipset despite there being a toggle for 55lbs injector mode. Chucked the originals back in and all good for my needs. I won't be looking for any more boost/power. I do have an uprated fuel pump though and a recently new fuel filter to help! The pump is a Sytec Motorsport one which is a Bosch 044 equivalent. (I know the injectors can only pump what they can pump but all seems fine)
Agree on manufacturer claims but happy enough my peak boost and held boost levels are well within safe parameters and I only run v-power in it which I think is 99 RON.
I think I'll eventually go down the EBC route and stick to a flat 18psi. Get the thing back on the road and run in first!!
Cheers
Stuart
blade7
Well-known member
scam75 said:blade7 said:
No, I'm on cleaned standard injectors and the fueling is all good, low 11's AFR at peak boost (21 psi). I had 55lbs injectors for a bit and the car never ran right with my chipset despite there being a toggle for 55lbs injector mode. Chucked the originals back in and all good for my needs. I won't be looking for any more boost/power. I do have an uprated fuel pump though and a recently new fuel filter to help! The pump is a Sytec Motorsport one which is a Bosch 044 equivalent. (I know the injectors can only pump what they can pump but all seems fine)
Agree on manufacturer claims but happy enough my peak boost and held boost levels are well within safe parameters and I only run v-power in it which I think is 99 RON.
I think I'll eventually go down the EBC route and stick to a flat 18psi. Get the thing back on the road and run in first!!
Cheers
Stuart
18lbs on standard injectors and a 3 bar fpr is all I'd be comfortable with. 25 years ago I used to rag my chipped 87 Cosworth in top gear all the time. I'm not so brave now though. Whatever boost you run, you'll get used to it. You have to draw a line somewhere. Do you feel lucky [
Some progress and updates.
Turbo fitted on a nice aquablasted pedestal mount with an AN fitting for the AOS drain. With that in place I could get the crossover pipe bolted up. I had the flanges cut off a set of turbo exhaust manifolds and tacked onto the 16v exhaust manifolds in situ then welded up properly and all bolted up.
Had the oil filter console modified to take some AN10 fittings so my other oil lines will attach straight up too.
Turbo fitted on a nice aquablasted pedestal mount with an AN fitting for the AOS drain. With that in place I could get the crossover pipe bolted up. I had the flanges cut off a set of turbo exhaust manifolds and tacked onto the 16v exhaust manifolds in situ then welded up properly and all bolted up.
Had the oil filter console modified to take some AN10 fittings so my other oil lines will attach straight up too.
Posts made and opinions expressed are those of the individual forum members
Use of the Forum is subject to the Terms and Conditions
