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About CefiroA31

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    Rank: RB20E
  1. So either stay stock on lower boost/rpm if go bigger get those valve springs, thank you for this.
  2. Thank you for the input, to clarify on first paragraph you mean replacing with new OEM damper or ATI/Fluidampr/Ross damper?
  3. Hi, is the engine in this test still on OEM stock valve springs? thank you.
  4. Managed to get the fitment info of RB crank dampers from Ross website, so only opinions/experiences on performance differences needed now.
  5. Hi, I am rebuilding a RB25DET Neo (may get an RB26 crank in it) so need advice on crank dampers + cams + valve springs. Purpose of the car for weekend fun in track days/drifts/drags/dyno comps, but also be a reserve to my daily driver, maybe use to get me to work for 1-2 days of a week. I have 3 Holset turbos of identical fitment so can switch between them as needed, smallest turbo should max at 60 lb/min, middle turbo at 80lb/min and biggest turbo at 100lb/min, biggest turbo will likely installed only for dynos/drags. Would like a powerband thats relatively responsive around town while revving up to 8000-8500 rpm. Plan is in the future (2-3 years) it may be rebuilt as a stroker. What is the limit of new OEM crank damper in either whp or rpm when aftermarket crank damper is needed? If upgrading to aftermarket crank dampers, what differences in performance/fitment between using RB26 crank dampers like from ATI or Fluidampr compared to Neo crank damper from Ross? Any camshaft profile recommendations best suited to my purpose? Opinions/experiences on Tomei Type A Poncam 252/9.15 mm, Kelford 264 in/272 ex/9.6 mm, or Camtech 264/9.5 mm or 272/9.7mm? At what boost and rpm when upgraded valve springs are needed (Per Hypergear Turbo thread, OEM valve springs seems to hold boost of near 30 psi just fine, dont know if current Hypergear max dyno result of 570rwkw at40 psi is on OEM valve springs or not)? Thank yous for any advice, cheers.
  6. I have an RB20E single cam engine that I fit with twin scroll turbo set up using Holset HX35/HX30 hybrid turbo, 12 cm t3 twin scroll turbine housing, small HX35 50 mm inducer compressor, HX30 52 mm exducer turbine and Turbosmart Hypergate 45 wastegate. I lost my dyno print out but from memory it made around 220 rwhp on 1 bar of boost and around 310 rwhp on 1.5 bar of boost (this for the dyno pulls only), fuel is 95 octane pump gas. On the street, 3rd gear starting from 2500 rpm cruise then go WOT boost starts around 2800 rpm. Dyno type used is a Dynomite dyno.
  7. Long time reader of SAU just created my account so can learn and share easier with users here. Hi Brian, to be clear of your current turbo, it has 58 mm inducer (smaller diameter) compressor and 64 mm exducer (smaller diameter) turbine? If your turbine has around 74 mm inducer (bigger diameter) then you seem to have a T4 P-Trim turbine wheel, which was used in Garret and HKS T04Z and were popular for RB26 and 2JZ in the 2000's. Its old technology but can work well as its still used in Garrett new GTW3884 (update of Garrett T04R/Z), and you can see from the turbine map at Garrett website that it has 73% peak turbine efficiency, better than newer GT35 GT40 turbines which has the closest flow rate to T4 P trim turbine. T04R/Zs have 66-67 mm inducer 84 mm exducer compressor good for 750 hp, while GTW3884s have 62-64-67 mm inducer compressor options rated by Garrett up to 800-900=950 hp. If you can source billet 62-67 mm inducer 84 mm exducer compressor then you will make an aftermarket wheeled GTW3884. Just make sure to order compressor wheel with the same bore size as your turbine shaft as there are small shaft and big shaft versions of T4 P trim turbine. Turbonetics 7868 is a bigger turbo, it uses Turbonetics better flowing version of Garrett T4 Q trim turbine, one size up from a T4 P trim turbine. For your target of 500 hp a 7868 turbine is overkill as the T4 P Trim turbine has made over 800 whp when used in GTW 3884 67 mm inducer compressor. So iI suggest its better to use your current turbo assuming it has a T4 P trim turbine and update it with a billet compressor (bigger compressor inducer means lazier response but higher max hp). If you want to optimise response you can also get a T4 twin scroll turbine housings for T4 P trim turbine, you can google AGP turbo and ATP turbo from USA for example to source those housings. In my experience converting to a twin scroll set up even with a single wastegate exhaust manifold similar to a 6 Boost RB25 manifold it gives quicker spool up with no loss of top end max hp. Hope this helps. Rian.
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