Project Pathfinder Part 8, Cams ECU Headers

Project Pathfinder Part 8, Cams ECU Headers

In our last edition we added some mods to help our weak legged Pathfinder with a much needed shot of power.  This month we do a few more things to help our car tow our SE-R Cup car without getting run over.                                   

Camshafts

The stock VG cam shafts are very mild.  At the advice of the guys at Nissan Motorsports we added a set of their #2 off road cams to Project Pathfinder.  The cams have 264 degrees of duration and .430” lift with a 106 degree intake and 116 lobe center as opposed to the tiny stock 248 degrees duration and .374” lift with 114 lobe centers.  This is quite a difference and the cams really woke Project Pathfinder up.  In fact the cams made more of a difference than any mod we have done so far.  We estimate that the cams were good for about 25 hp over stock.  The power increase comes across the board with more power from idle to the fuel cut.  The Nissan Motorsports cams work with the stock valvesprings.  The only drawback is that they have a slightly lumpy idle due to the much tighter lobe centers which actually sounds sort of cool.  In town fuel economy has remained the same but the improvement in highway and towing mileage has been incredible increasing by 4 mpg.  This is because the added power helps the big Pathfinder travel down the road with less strain.  I highly recommend these cams as the best Pathfinder engine mod possible.  If you have a newer Xterra or Frontier with the bigger VG33E engine, these same cams will wake your motor up even more to the tune of 40 or more hp because the newer VG’s are saddled with even smaller stock cams.  An older Z31 300ZX can also benefit greatly from these cams.                                                                 

JWT ECU

We added JWT’s ECU to help improve mileage and throttle response as well as to improve idle quality with the cams.  JWT’s Clark Steppler did a custom tune to enable us to get the best power from weak 87 octane gas although we do switch to 89 for towing.  The VG30E’s low 8.8:1 stock compression allows for ECU tuning even with poor gas.  The JWT ecu made a noticeable increase in power, improved throttle response and improved fuel economy. 

To help improve engine efficiency, we also added a set of Doug Thorley Headers.  Old Pathfinders tend to crack their exhaust manifolds and ours was no exception.  We replaced our leaking and cracked exhaust manifold with headers.  Doug Thorley headers are CARB approved so smogging your car will be no hassle.  They are a high quality part made with thick flanges and thick gauge tubing for long life.  To reduce rust they are also chrome plated.  The Doug Thorley headers are designed for good midrange torque, just right for an underpowered and heavy SUV.  The headers made an impressive difference running a close second to the cams in improvement as the best mod.  The difference in midrange power was quite noticeable.   

Doug Thorly Headers

Project Pathfinders fuel economy improved from a Pathetic 15 mpg in town, 19 highway and 10 towing to a much improved 19 in town, an amazing 24 mpg highway and 12-14 mpg towing.  Power for towing has improved quite a bit.  When towing our race car with a two axle trailer we can now go 65 mph up the dreaded grapevine pass while towing.  Stock we struggled to maintain 50 mph here.  In an impromptu race with a late model VQ35DE powered Pathfinder, Project Pathfinder surprised us by beating the newer 240 hp faster Pathfinder.  In future editions we will get into the engines internals to make a real sick tow monster.  Look out F150!

Sources

Nissan Motorsports

Doug Thorley 

Jim Wolf Technology