BOOST SE­LEC­TION

NZ Performance Car - - Inside Line -

Dar­ren’s big­gest con­cern with the new build was to en­sure that the en­gine made good power from around 3000rpm and right through to rev limit. With Rich en­sur­ing that the head flowed a mas­sive 270cfm, a new Gar­rett GTX3584RS turbo was tasked with mak­ing the boost. Tim from TTT Auto Engi­neer­ing built a new six-into-one stain­less man­i­fold, us­ing sched­ule 10, 304L stain­less. The run­ners are a 40mm in­ter­nal di­am­e­ter and as close to equal as Tim could achieve in the space, which he told us is ac­tu­ally tighter than in the old R34 chas­sis: “The big­gest thing I con­cen­trated on was en­sur­ing [that] the run­ners had good flow. Not tight-ra­dius bends, just nice and flow­ing.” The water-cut flange was first port matched to the ported head, and then bolted to a large piece of al­loy for weld­ing. Do­ing this en­sures the flange stays flat, as al­loy is a great dis­si­pa­ter of heat. “Af­ter tack­ing each run­ner in place, I then purge welded, which en­sures you get full pen­e­tra­tion,” Tim said. ‘Purge weld­ing’ is a tech­nique where ar­gon is flowed through the part to en­sure you have shield­ing on both sides of the ma­te­rial be­ing welded.

Both the Turbosmart Comp-Gate 40 waste­gates will feed out of the block for the fore­see­able fu­ture, and, although Mo­tor­Sport New Zealand (MSNZ) does not al­low this, the next two events Dar­ren will con­test, do. Fin­gers crossed that the new law is passed be­fore the D1NZ sea­son starts; if not, they will be plumbed back into the down­pipe. If this hap­pens, Tim will re­place the new three-inch down­pipe with a 3.5 inch.

“The big­gest thing I con­cen­trated on was en­sur­ing [that] the run­ners had good flow”

Rich elected to use a 1mm Per­maseal MLS-R head gas­ket, which is ac­tu­ally a four-layer gas­ket

Newspapers in English

Newspapers from New Zealand

© PressReader. All rights reserved.