Twin scroll turbo upgrade MD321 billet or SC42 billet or LM420 billet?
12 August 2012, 08:01 PM
#121
Ecu Specialist
John the slightly faster spool on the V Power only setting is due to the retarded ignition used to accommodate that fuel, it heats the turbo/exhaust gas and so aids spool.
Mark, Johns boost peaked at 1.85, but his held boost is 1.6 tapering down due to the intake pipe, my boost does the same as I have still got a soggy pipe on it !! (hint)
John will confirm I have been very critical of previous turbo iterations but this version seems to do the business.
Since I have now mapped several cars using both the Chevron ultimate F1 cored TMIC and the lower cost budget version I have to say they are impressive, the f1 core is fantastic and on the road is the equal of a FMIC. But, yes, its expensive, the core is the very same used for F1 coolers (oil, fuel etc) and is very high efficiency.
I personally played a bit "safe" at the time but I was VERY tempted to use on on my own car. fair play to Simon he never put any pressure on though.
One other thing to mention about Chevron if you are considering suspension and setup then Simon is the man when it comes to this and he will be sorting my car out for me no question.
Finally John as we have been discussing looking forward to the next session when we should be able to raise the bar yet again.
cheers
bob
Mark, Johns boost peaked at 1.85, but his held boost is 1.6 tapering down due to the intake pipe, my boost does the same as I have still got a soggy pipe on it !! (hint)
John will confirm I have been very critical of previous turbo iterations but this version seems to do the business.
Since I have now mapped several cars using both the Chevron ultimate F1 cored TMIC and the lower cost budget version I have to say they are impressive, the f1 core is fantastic and on the road is the equal of a FMIC. But, yes, its expensive, the core is the very same used for F1 coolers (oil, fuel etc) and is very high efficiency.
I personally played a bit "safe" at the time but I was VERY tempted to use on on my own car. fair play to Simon he never put any pressure on though.
One other thing to mention about Chevron if you are considering suspension and setup then Simon is the man when it comes to this and he will be sorting my car out for me no question.
Finally John as we have been discussing looking forward to the next session when we should be able to raise the bar yet again.
cheers
bob
12 August 2012, 08:19 PM
#122
Thanks Bob, this is the third turbo spec made for us to test, Lee Owen has stuck at it and listened to the feedback we have been giving and finally come up with something special IMHO, it's been great that you've stuck with it too and put the work in to help get us where we are now.
With the other changes in place and the mapping based around the turbo speed info (we have a speed sensor on the turbo) it can only get better.
Simon and the guys at Chevron should also take a lot of credit for where we are now, they have some great bespoke products available for the Impreza.
I competed at the first 3 MLR/22B Sprints with the earlier versions of turbo, i cant wait to see how it goes at the next one.
With the other changes in place and the mapping based around the turbo speed info (we have a speed sensor on the turbo) it can only get better.
Simon and the guys at Chevron should also take a lot of credit for where we are now, they have some great bespoke products available for the Impreza.
I competed at the first 3 MLR/22B Sprints with the earlier versions of turbo, i cant wait to see how it goes at the next one.
06 October 2012, 10:19 PM
#123
New reinforced Inlet pipe is now on the car, 4 BAR MAP sensor is here, Spec C IC water spray tank is with me, loom for that made so will go in tomorrow. New Chevron combined water radiator and oil cooler installed.
So all set for mapping on Wednesday.
So all set for mapping on Wednesday.
07 October 2012, 08:20 PM
#125
I'll drop Charlie an email and see if he can do it on Thursday, off up north Friday for the MLR/22B sprint final.
Paulo Spec C should be interesting to watch there, he now has the same spec turbo as mine on a stock MY03 Spec C engine and Chevron TMIC, being mapped tomorrow.
Paulo Spec C should be interesting to watch there, he now has the same spec turbo as mine on a stock MY03 Spec C engine and Chevron TMIC, being mapped tomorrow.
07 October 2012, 09:21 PM
#126
I'll drop Charlie an email and see if he can do it on Thursday, off up north Friday for the MLR/22B sprint final.
Paulo Spec C should be interesting to watch there, he now has the same spec turbo as mine on a stock MY03 Spec C engine and Chevron TMIC, being mapped tomorrow.
Paulo Spec C should be interesting to watch there, he now has the same spec turbo as mine on a stock MY03 Spec C engine and Chevron TMIC, being mapped tomorrow.
11 October 2012, 05:16 PM
#127
Been over to Charlies today, it's lost some power at the top end but gained torque and mid range in general. The engine is running 1.5-2 degrees less ignition and is a bit richer, which is probably where the power has gone on the rollers, i'll do some logs on the road when i can to see if it's less affected on the road in the same way. (its road mapped)
So it's currently showing 490lbft @ 3700rpm, 435BHP @ 6500rpm. peak boost on the rollers was 1.85BAR @ 3500rpm (it pulls 1.95BAR on the road).
Mid range acceleration is very impressive now!
Graphs show the previous run and current run with 20% meth.
Power/Torque
Power/Boost
So it's currently showing 490lbft @ 3700rpm, 435BHP @ 6500rpm. peak boost on the rollers was 1.85BAR @ 3500rpm (it pulls 1.95BAR on the road).
Mid range acceleration is very impressive now!
Graphs show the previous run and current run with 20% meth.
Power/Torque
Power/Boost
Last edited by johnfelstead; 11 October 2012 at 05:18 PM.
11 October 2012, 05:44 PM
#128
Scooby Regular
Cracking spool John! 
It's actually showing as near as damn it 476ftlb but I'll let you off because of your old age and poor eyesight!
Bet you're happy overall!
It's actually showing as near as damn it 476ftlb but I'll let you off because of your old age and poor eyesight!
Bet you're happy overall!
11 October 2012, 05:47 PM
#129
It pulled more the previous run Shaun, but thats the one that was printed. Ask charlie if you doubt me.
Charlie was having fun trying to keep the thing in the rollers yet get a power run done OK.
Yes, very happy with it, it does exactly what i asked for.
Charlie was having fun trying to keep the thing in the rollers yet get a power run done OK.
Yes, very happy with it, it does exactly what i asked for.
Last edited by johnfelstead; 11 October 2012 at 05:49 PM.
11 October 2012, 06:30 PM
#130
Scooby Regular
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Good result John I will have to scrounge a passenger ride off you on saturday at Teeside and see what its like.
11 October 2012, 07:05 PM
#132
Scooby Regular
I don't doubt you John...... I just (logically) assumed that your eyes were having problems, based on the back-up evidence you supplied.
15 October 2012, 04:01 PM
#135
I've ended the season runner up in the S2 championship, with a 2nd place at Teesside.
Paulo Spec C won the S2 championship using a stock 2.0 MY03 Spec C engine in his MY03 Spec C, the last two rounds he won using the new Owen Developments twin scroll turbo, winning Castle Combe with a stock TMIC, winning Teesside with a Chevron TMIC.
So a 1-2 in S2 class for Chevron supported cars using this new Owen Developments Twin Scroll turbo, with 5 wins from 7 rounds (i missed two rounds due to work commitments). 3rd in the S2 series also had some support from Chevron motorsport.
Paulo Spec C won the S2 championship using a stock 2.0 MY03 Spec C engine in his MY03 Spec C, the last two rounds he won using the new Owen Developments twin scroll turbo, winning Castle Combe with a stock TMIC, winning Teesside with a Chevron TMIC.
So a 1-2 in S2 class for Chevron supported cars using this new Owen Developments Twin Scroll turbo, with 5 wins from 7 rounds (i missed two rounds due to work commitments). 3rd in the S2 series also had some support from Chevron motorsport.
15 October 2012, 04:15 PM
#137
Yes, Paul was using a stock VF36 until Castle Coombe.
Owen havn't oficially released the turbo yet, it will be happening shortly, this year has been about refining the spec and testing it on road and in competition.
It's probably best to speak with Simon at Chevron Motorsport who will be the retail outlet for these turbos.
Owen havn't oficially released the turbo yet, it will be happening shortly, this year has been about refining the spec and testing it on road and in competition.
It's probably best to speak with Simon at Chevron Motorsport who will be the retail outlet for these turbos.
15 October 2012, 05:05 PM
#138
Scooby Regular
16 October 2012, 08:36 PM
#144
Cheers Fud, was a great laugh having you in the mix.
Just waiting on the new regs for next year to see if i have to do anything to the car, or just leave it as is and drive the wheels off it.
Just waiting on the new regs for next year to see if i have to do anything to the car, or just leave it as is and drive the wheels off it.
22 November 2012, 12:59 AM
#145
OK, we did some more work on the mapping yesterday and also found why we lost power with increased boost.
The OEM dump valve wasn't sealing fully it appears, which would have been feeding hot air back into the turbo inlet. So we fitted a Forge recirculating dump valve and did another mapping session on the road.
It instantly picked up 0.25BAR and sharpened up the response even more, so after mapping the car and spending a bit of time fine tuning the cruise AFR's etc. now the pressure of time had gone for the sprints i was doing we have achieved the following.
Power of 473 BHP, Torque of 540 FtLb !
Power and Torque
Power and Boost
The engine knocked a bit of timing out at the top end on the rollers, it doesn't on the road. This is a road mapped car, there is no attempt to optimise the engine for the rollers. It looks like on the road it's producing 490 BHP
That'll do!
The OEM dump valve wasn't sealing fully it appears, which would have been feeding hot air back into the turbo inlet. So we fitted a Forge recirculating dump valve and did another mapping session on the road.
It instantly picked up 0.25BAR and sharpened up the response even more, so after mapping the car and spending a bit of time fine tuning the cruise AFR's etc. now the pressure of time had gone for the sprints i was doing we have achieved the following.
Power of 473 BHP, Torque of 540 FtLb !
Power and Torque
Power and Boost
The engine knocked a bit of timing out at the top end on the rollers, it doesn't on the road. This is a road mapped car, there is no attempt to optimise the engine for the rollers. It looks like on the road it's producing 490 BHP
That'll do!
