Pocket ported head ready to go w bronze guides

Description

Pocket port good for 7200-8000 rpm peak power.

400-600 rpm better spool

Typically, 5-11 psi boost reduction for the same power in the same set up.

Ratings below on a scale of 1-10 how good this cylinder FK8td ported head will perform for the application compared to stock.

******This does NOT apply to other companies’ cylinder head port work*******

Drop in turbo power gains                                                   stock=5-6                              ported =7-10

Full Frame turbo power gains                                            stock=5-6                              ported=7-9

Street manners                                                                       stock= 9                                 pocket ported= 9

Drag strip use                                                                          stock=3                                 pocket ported =8

Circuit racing or autocross                                                   stock =5                                 pocket ported =10

Roll racing                                                                               stock=1-5                              pocket port =7-10  (rating relevant to turbo size)

Turbo spool and lag response on a drop in turbo            stock=3-5                              pocket ported =9-10

Turbo spool and lag response on a full frame turbo       stock=1-5                               pocket ported =9  (g25-660.72 ar works ok stock head, larger ar and turbo do not)

Boost reduction for the same power using camshafts   stock=2-6  psi                       pocket ported =10-16 psi reduction for the same hp.

Cold start manners                                                                stock= 10                               pocket port=9

Cold engine drivability                                                         stock=10                                pocket port=9.5

Fuel efficiency                                                                        stock=10                                pocket port=9.5 (2-3 mpg loss may or may not occur)

Knock sensitivity near timing limit                                   stock=4                                  pocket port= 8  (less sensitive to timing making tuning safer and easier near the limit)

Peak power capability  (gains grow w turbo size)          stock=3-5                              pocket port= 8 (mhi 30whp  g25-660 55-60whp g30-770 up t0 70-80whp g35-1050 80-90whp

Minimum size turbo recommended                                 stock=stock turbo                pocket ported= mhi stage 2 or turbos with larger compressor wheels suggested

Typical gains per the turbo are (mhi 30whp,  g25-660 55-60whp, g30-770 up t0 60-80whp, g35-1050 80-90whp)

***mhi stage 2 power was at 25 psi to make 545 and carried from 7000-7500 flat***

Gains are mostly exponential with turbo size using ported heads and you must have enough fuel.

Peak power capability estimated at 800whp. Its possible to make depending on turbo, fuel and compression. Exhaust outlet flange diameter is most of the limiting factor. Thes estimation is using a heavy roller Dynojet and not a hub dyno.

Pocket ported

Valve job on Serdi (our custom seat cut)

Cleaned and ready to assemble

Bronze guides installed

not returnable