Swedbrick
Active member
- Joined
- Oct 12, 2016
- Location
- Netherlands, Source of Grolsch
An update once more
Hi, along with the update concerning the twin turbo manifold on the engine thread, I'll update you all on the progress on the car itself.
Starting off, I'll give a little insights into why twin turbo with two 13c's. I noticed with my first 13c that the opening in the housing is approximately 2 exhaust ports for the b230, resulting in quite a restriction, but with low rpm spool. Given that my experience with my brothers b230ft was a lot of fuel consumption and surging behavior whilst cruising at 130km/h due to this turbo setup, I decided I would like my turbo's to spool higher, around 4000 rpm (since the short ratio's I currently run put the tach at 3.5k at cruising speed already), assuming that 7000 rpm would be achievable, resulting in a useable 3k powerband.
With the reduced restriction in the exhaust path, and a better flowing exhaust and intake manifold and a big cam, this should be obtainable. I set my power goal at 350whp, since a single 13c maxes out at about 220hp, and with a better flowing head, the doubled cfm maximum for the two turbo's and the max boost pressure of 14psi should allow for this goal if I manage to remove enough restriction from the air path in the head.
To solve the issue of one of the turbo's generating more of the airflow than the other, I will apply the bank crossing technique as commonly applied with turbocharged v engines. Where the two cylinders powering one turbo are fed air by the other turbo to created a system where both banks naturally balance. Since this also requires for the creation of 2 new intake manifolds, I will be upgrading to ITB's from a GSXR, with some sheet metal manifold goodness.
The fuel and ignition will remain LH2.4, with a translator in between two stock MAF's to the cfm/voltage profile expected for a 960 maf given the airflow measured across the two stock MAF's. I will probably run green giants, with blabla's 960 maf and 7k rpm redline chips, if I do not decide to get in to chip burning myself
Hi, along with the update concerning the twin turbo manifold on the engine thread, I'll update you all on the progress on the car itself.
Starting off, I'll give a little insights into why twin turbo with two 13c's. I noticed with my first 13c that the opening in the housing is approximately 2 exhaust ports for the b230, resulting in quite a restriction, but with low rpm spool. Given that my experience with my brothers b230ft was a lot of fuel consumption and surging behavior whilst cruising at 130km/h due to this turbo setup, I decided I would like my turbo's to spool higher, around 4000 rpm (since the short ratio's I currently run put the tach at 3.5k at cruising speed already), assuming that 7000 rpm would be achievable, resulting in a useable 3k powerband.
With the reduced restriction in the exhaust path, and a better flowing exhaust and intake manifold and a big cam, this should be obtainable. I set my power goal at 350whp, since a single 13c maxes out at about 220hp, and with a better flowing head, the doubled cfm maximum for the two turbo's and the max boost pressure of 14psi should allow for this goal if I manage to remove enough restriction from the air path in the head.
To solve the issue of one of the turbo's generating more of the airflow than the other, I will apply the bank crossing technique as commonly applied with turbocharged v engines. Where the two cylinders powering one turbo are fed air by the other turbo to created a system where both banks naturally balance. Since this also requires for the creation of 2 new intake manifolds, I will be upgrading to ITB's from a GSXR, with some sheet metal manifold goodness.
The fuel and ignition will remain LH2.4, with a translator in between two stock MAF's to the cfm/voltage profile expected for a 960 maf given the airflow measured across the two stock MAF's. I will probably run green giants, with blabla's 960 maf and 7k rpm redline chips, if I do not decide to get in to chip burning myself