Jump to content
SAU Community

Stock 26 Head Vs Modified 25

WHITER33GTS-T
 Share

Recommended Posts

blue_vl_t Rising Star

blue_vl_t

Posted
Posted

Rob what was changed though?

as really the rb25 head ports are the same as rb26, so i'd say your extra power was made from cam selection/solid lifters, head modification, intake plenum and the fact you are running 2psi extra boost. All which could be done to the rb25 head if someone was keen.

correct me if im wrong :thumbsup:

WHITER33GTS-T Veteran

WHITER33GTS-T

Posted
  • Author
Posted

The 26 head was ported, oversize valves, 280 10.8mm cams, stock inlet, 6Boost manifold, Garrett T51r

The 25 head was ported, tomei 256in and 264ex cams, Greddy plenum, 80mm throttlebody, 6Boost manifold, Garrett T51r

blue_vl_t Rising Star

blue_vl_t

Posted
Posted

Fair few differences, must have quite an idle with 280 cams :O

Who ported the head for you?? do you know what was done, was it ported for drag racing, outright power or mild post, smaller ports etc for all round performance? you running 1mm oversize on the intake and exhaust?

Do you have this going at the moment rob? or still having problems/rebuilding/upgrading :D

WHITER33GTS-T Veteran

WHITER33GTS-T

Posted
  • Author
Posted

Proengines built the head after I was screwed over by a local mechanic (you know who)

Am running oversize on intake and exhaust. There was a flow chart posted on here somewhere of my head.

The engine has been in the car since August but just had to pull the sump off as it didnt seal. The goal is to have it running for powercruise next year.

We will fire it up on 98 and make sure everything is all good then will drop in the 2000s and get into the E85 :thumbsup:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • iain_ST44GA
      M35 VQ25DET starter motor

      By iain_ST44GA · Posted

      Hi Guys, Does anyone know any aftermarket part numbers for a starter motor to suit the VQ25DET? I can find lots of alternative part number for the VQ35DE, which I assume would fit, but there is a lot of conflicting information out there. Thanks..
    • Murray_Calavera
      R33 GTR running -9 with no tune

      By Murray_Calavera · Posted

      I don't understand how this hasn't boiled down to - Upgrade the turbo when you have everything required. ECU, injectors, fuel pump, turbo, etc. Do it all at once.  If you don't have everything required, just enjoy the car as it is and keep saving up your pennies. 
    • Duncan
      R33 GTR running -9 with no tune

      By Duncan · Posted

      Sounds like you've got an interesting adventure ahead here with local support if you have trouble! My guess is that, unboosted, you will be OK with a small upgrade like -9. What will happen is that once the stock ECU sees more airflow than it expects it will add a heap of fuel and pull a heap of timing to be safe because it can't understand how it could get that much air without there being an issue. You will see clouds of black smoke and it won't pull hard through the midrange and top end. So, overall it will be a bit frustrating but should be OK. If you are still nervous set the base timing back 2o through the CAS, but it will be even more sluggish everywhere. As said above through...this is not my guarantee your engine won't be blown into a million pieces, leaving you looking for very hard to find parts A better idea is get a computer with logging ASAP, wire in a wide band O2 sensor and a use remote tuner. I've done multiple cars this way and while it is not as good as a specific tune on a dyno they can get it 90% right. I'd suggest if you can afford an R33 GTR these days you can afford an ECU and tune. And if you can't afford that you sure won't be able to afford the rebuild if it goes bad in the meantime,.  
    • Duncan
      New kid on the block

      By Duncan · Posted

      Yeah it would be nice if someone took the time to put that sort of information together, but there are a lot of variations in looms. I think you are making this way hard for yourself if you just want to get it running....sourcing an SR20 with the right wiring will be a billion times easier than matching the RB loom to an S15 chassis. If you do end up going this way, you just need to trace every wire in the loom with a multimeter, 95% of them will go to a location you can confirm at the ECU.....and then post it up for the next person who needs it  
    • Duncan
      Coolant leak?

      By Duncan · Posted

      Just top it up with water, and keep a general idea of how much you added. It is normal for water to be pushed into and pulled out of the reservoir through the cap, and it should not be more than half full or it will be likely to overflow when hot. Any decent mechanic can do a pressure test of the cooling system to confirm if you have a leak. Keep in mind if it is only leaking a little and when hot it may well evaporate before you see it hit the ground
×
×
  • Create New...