by The JD » Wed Oct 07, 2009 1:38 pm
150bhp indeed for the R75, whereas the MG-ZT is rated 160. Not sure where the difference is.. with the demise of Rover and the turbo-K being scarce theres little data available. What I do know is the K-Turbo does produce 200lb/ft v 100lb/ft for NA (normally aspirated). Ive noted the TB is the smaller variety but with forced induction it just doesnt matter, I mean the head and valves are stock 1.8L items, no way near VVC/Trophy160 sizes.
Theroy sais (general chatter) you can have as much power (torque) as you wont as long as the engine holds! So, boost, well I tightened the actuator fractionally to take out any wear (+60k donor engine) and with zero PWM (max positive feed back from pressurised induction) was seeing 10-12psi on Emerald logs from the MAP sensor.
So I created 2 additional maps (Emerald has 3 you can switch on the fly from the dash) with 40% PWM bleed signal at 4000rpm map1 and 80% PWM bleed signal map3. Having scared the daylight out of me on map1 ~10psi I briefly tried map2 and decided that I could push the pedal down more than a 3rd! Just to wild.
So yesterday I went for a spin with Dawsey (holding laptop to datalog) and after 2 miles the engine exploded oil and water mixed like custard!! Turns out I was running map3 and the log showed 24psi which is more than a cossy!! Whipped off the head and found much like Wisp but worse debonding of the butyle rubber on the H.Gasket. Indeed mine had completely debonded and suspect this was already considerably underway before I raised the head off the block (with boost I mean!).
Head was in very good nick just standard indentation from flame rings which I believe occurs regardless over time, if it digs in around the hot exhaust side then yer thats overheating and annealing of the ALU.
I have a spare MLS which should work nicely and am sourcing an uprated bottom rail. so should be back on track by the weekend.
150bhp indeed for the R75, whereas the MG-ZT is rated 160. Not sure where the difference is.. with the demise of Rover and the turbo-K being scarce theres little data available. What I do know is the K-Turbo does produce 200lb/ft v 100lb/ft for NA (normally aspirated). Ive noted the TB is the smaller variety but with forced induction it just doesnt matter, I mean the head and valves are stock 1.8L items, no way near VVC/Trophy160 sizes.
Theroy sais (general chatter) you can have as much power (torque) as you wont as long as the engine holds! So, boost, well I tightened the actuator fractionally to take out any wear (+60k donor engine) and with zero PWM (max positive feed back from pressurised induction) was seeing 10-12psi on Emerald logs from the MAP sensor.
So I created 2 additional maps (Emerald has 3 you can switch on the fly from the dash) with 40% PWM bleed signal at 4000rpm map1 and 80% PWM bleed signal map3. Having scared the daylight out of me on map1 ~10psi I briefly tried map2 and decided that I could push the pedal down more than a 3rd! Just to wild.
So yesterday I went for a spin with Dawsey (holding laptop to datalog) and after 2 miles the engine exploded oil and water mixed like custard!! Turns out I was running map3 and the log showed 24psi which is more than a cossy!! Whipped off the head and found much like Wisp but worse debonding of the butyle rubber on the H.Gasket. Indeed mine had completely debonded and suspect this was already considerably underway before I raised the head off the block (with boost I mean!).
Head was in very good nick just standard indentation from flame rings which I believe occurs regardless over time, if it digs in around the hot exhaust side then yer thats overheating and annealing of the ALU.
I have a spare MLS which should work nicely and am sourcing an uprated bottom rail. so should be back on track by the weekend.