Jump to content
SAU Community

Recommended Posts

Hi I'm in need of some advice, so hears the story........

I have a r33 GTR with HKS gt-rs turbos, HKS manifolds, dumps etc. and all supporting mods. On a standard motor internally it made 460hp at 18psi.

Now have a built motor with 264 deg cams, valve springs etc etc. got on the dyno the other day. The car wouldn't make boost. Re routed some vaccum lines and seemed to fix the problem. Then te car was making 22psi and started making less and less boost. Te end result was 350hp at 15psi which is shithouse. Now here's the kicker. The boost gauge and apexi avcr both tea 1.30 kg/cm2 however it was only making 15psi on the dyno. Turning the boost up to 1.70kh/cm2 on the avcr and both the avcr and boost gauge read that but no difference in power.

I have replaced the exhaust going larger thinking it could have been an issue, made it rev freerer but did not fix the issue.

Could this be an issue with vaccum lines run incorrectly? Any other suggestions as to whatnot could be?

Link to comment
https://www.sau.com.au/forums/topic/419404-built-gtr-not-making-power/
Share on other sites

Car is running currently on waste gate with the boost controller turned off and it's reading 1.30 kg/cm2. I believe the adjustable actuators aren't set exactly the same cause in getting a bit of turbo shuffle, but surely that can't be the main issue

Making less and less boost?

I had the same problem, ended up been a split in the intercooler hose that connects to the Twin Turbo pipe, but it was underneath and you couldn't see it

i agree if it was making less and less boost it sounds like you have a leak,

do the "twin turbo pipe mod" to try and eliminate that shuffle

check to BOV's are hooked up correctly i often see the vac/boost reference line swapped around with other lines in the vicinity and they bleed boost like nothing else... on a std gtr its around a 40rwkw loss.

Just compressed air works well, make up a bung for the intake of the turbo and pump 30psi into it. Blowing bong smoke up there just makes the escaping air easier to see but you will hear any leaks just fine.

ill try to pressure test/smoke test it this weekend. As far as vbaccum lines are concerned it is certainly possible that i have my vaccum setup incoreect. ive been searching etc, but cant seem to find a difinitive answer on it all.

i have double checked my vaccum lines etc and they all appear to be as they should. i noticed the other day when the car gets warm it idles at around 1300-1400 rpm, so that to me suggest vaccum leak. however ill check the intercooler piping and go from there

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


  • Similar Content

  • Latest Posts

    • Seat of the pants assessment of the new intake: The car is way less "doughy" when hitting the loud pedal, especially off idle when stopped or in traffic, I did use a cheapo lazer thermal thingo to measure the temp around where the pod filter got its air, it was between 55 - 60°C, in saying this the car was shut off and not moving, so the OEM intake pipe was not supplying any fresh air to where the pod was when the car was at least moving A weird bonus was induction noise on the throttle in the cabin increased a bit,  I was worried that I was actually going to lose some of that induction noise I love so much, outside though, when I got the daughter to do a WOT drive by pass for me, the induction noise has increased alot when on the throttle, not quite ITB doort, but well up there I'm extremely happy with the results and have been exploring the country roads in the region  As for house mods: 1.New front fence is up and is awesome, it really upgraded how the joint looks from the street, and the added security is nice 2. Electricians have replace some interior lights, and with more lighting in the garage, a few new motion detecting lights out the front above the garage, front room, and at the front door, which I have already found heaps helpful coming and going, also now has fancy pants CCTV all round the house The only hold point for power though is the solar and batteries due to supply issues, although this will happen over the next few weeks 3. I have done a heap of landscaping out the front and I'm almost ready to do a new small retaining wall with some nice blocks to replace the brick and cemented in rocks around the raised garden beds cemented in river stone "was the fashion at the time" the house was built. I currently have a pallet of retaining wall blocks and 2 bulka bags of 20mm blue metal to replace the wood chip that is in the raised garden beds around the house 4. I now have 3 big raised garden beds for out the back to grow some vegetables, about 70cm high, 200cm long and 100cm wide 5. My 2 compost bins are already pretty full with brown, green and kitchen waste from the landscaping I'vedone so far, but they will probably take a few months to break down, so anything else that gets chopped, trimmed, and kitchen waste will just start filling the base of the raised garden beds to about 30cm before I start throwing 40cm of good compost, and stuff, for the vegetables to grow in, I'll need a few ton of compost and soil, but the local supplier can sent me bulka bags of the stuff Basically the logs, wood chips and a few strategically placed rocks for drainage, will give the beds some good organic materials down low to break down over time, and they will hold moisture during the warmer months to save the water in my big arse water tank if we don't get alot of rain So, all in all, the car and house mods are going well, and I'm really enjoying being retired, I sleep in too 0700 and slowly plod around inside until I feel like actually doing anything, and only work in the yard for as long as want, which has actually been alot over the last few weeks,  although when you look at it, it seems that not a huge amount of work has been done,  until I look at the before I started the work pics Happy days and good times indeed 
    • hahaha yeah. Plan is to get side skirts and probably just rear pods. But going to do them one-by-one. I've got a set that I really like from RHDJapen, but that one isn't shipped to AU. So need to find someone who can get it for me
    • Here's an idea, answer the questions I asked you as they are trying to work out WHY the LSD will be binding up in a straight line.
    • You haven't driven many modern cars then have you? Most of them have sfa steering feel with their stupid electric bullshit steering systems.
×
×
  • Create New...