Jump to content
SAU Community

Recommended Posts

Hello SAU, been a long time lurker and decided I will taint my record with a thread like this.

Currently running a S2 RB25, Greddy IM, Precision 6062. Made 496whp at 20psi and I am wondering if pon cams would suit my setup. I am planning on going E85 soon and as I am doing my timing belt maintenance now, I thought what better time to go for cams than now? I wanted to gather some information from anyone else with a similar setup. 

Link to comment
https://www.sau.com.au/forums/topic/480475-cam-recommendation/
Share on other sites

Proven low reading dyno here in Tampa Fl, hence the discrepancy. If I could get the power to come on earlier that really would be my goal. E85 will get the extra punch out of it but I am looking for a wider power band. Boost leak tested, turbo bolts are snugged up, manifold to head bolts snugged up. That dyno day my injector seals blew out and we didn't notice theem, as well as running an electronic boost controller that caused some unpleasant wastegate fluttering. full boost hits at 5k-5.5k rpm all the way to redline. Since then I've swapped out the seals, and switched to a mbc and turbo does not feel as lazy, but power still comes on late in my opinion. Haven't seen many running this turbo as I would love to compare the differences.

IMG-0905.jpg

No aftermarket (larger) cam is going to bring your boost on earlier.

Any longer duration will only move the power curve to the right.

You can of course change the opening and closing event timing by a few degrees with adjustable cam gears. You could do this on stock cams to try to reduce overlap and move the curve to the left a little.

Increased cam lift is "free" power and can improve boost response by getting more gas flowing at lower revs. But more lift is seldom available without more duration. So it's nearly impossible to tease apart the response benefit from increased lift on a Poncam from the penalty from increased duration. And these are usually installed with gears, so it gets further muddled.

Poncams are far and away not the best choice for baby cams. There are a couple of Australian and NZ cam manufacturers who do more interesting cams, combining modest increases in duration with the largest lift that can still "drop in", or even better, with lift that requires clearance machining of the head.

What kind of ECU do you have? What's an MBC? If its a manual boost controller you would be better to change it for a Mac valve and use your ECU for better boost control in each gear (supposing your ECU supports that).

  • Like 1

Gotcha. The more I look into it, it seems like my car is performing as it should. videos of others running a .82 ar on a 25 all seem to be hitting full boost around 5k. I guess I could've gone with a .63 and had full boost in 3.5k rpm but who wants a car that can only do 500hp? More boost and e85 is the way to go I guess. Thanks for the advice 

4 minutes ago, KiwiRS4T said:

What kind of ECU do you have? What's an MBC? If its a manual boost controller you would be better to change it for a Mac valve and use your ECU for better boost control in each gear (supposing your ECU supports that).

Currently running a RS Enthalpy Z32 chipped ecu. Boost by gear or boost by tps would be awesome if I go aftermarket engine management. Car is loads of fun as it is... after e85 will be the point I'll have run out of things to do that don't involve engine overhaul

15 hours ago, KiwiRS4T said:

Here's a guy running a 6062 (on E85) making 700hp

https://www.sau.com.au/forums/topic/313603-precision-billet-turbos/page/140/

Scroll down to R33 Ryan on p 140 of the Precision thread

Seen it as well, someone on that thread seems to be having/had the same issue. running moderate boost (17-21psi) and it only kicks on at 5.5k rpm. Boost leak tested it again as well as ran it with a smoke machine and still can't find anything. 

I think the money you would spend on cams would be better spent on a Link or  a Haltech so that you can better control boost build.  Also a lot is in the tune. Most tuners work on the basis that customers want to see as high as possible maximum power figure (which is too often the case). If you get a better ECU and tell your tuner what you want to achieve I think you will have better success. 

  

38 minutes ago, KiwiRS4T said:

I think the money you would spend on cams would be better spent on a Link or  a Haltech so that you can better control boost build.  Also a lot is in the tune. Most tuners work on the basis that customers want to see as high as possible maximum power figure (which is too often the case). If you get a better ECU and tell your tuner what you want to achieve I think you will have better success. 

Nistune Boost control is actually very good, you have the option of a 3D table.

 

wow.. a RB25 coming on at 5~5.5k with only 500hp rear is pretty terrible.

Question around your manifold setup, is it divided or open? Please post up a photo of your hotside. Also cams won't bring on your boost any sooner, I would look at seeing if your VCT is working, without that you're already sacrificing 500~600rpm of spool time.

(bragging rights) I was doing 499hp at the rear on a Mainline dyno with semi-slick tyres. Hit 1.65bar by 4100rpm.

13254873_1752196888370888_1071539108639925081_o.thumb.jpg.1f31e653945e2daa8595dd41e87ba95b.jpg.91adec3ff4f55d63c8406b5ed5377909.jpg

4 hours ago, Dose Pipe Sutututu said:

  

Nistune Boost control is actually very good, you have the option of a 3D table.

 

wow.. a RB25 coming on at 5~5.5k with only 500hp rear is pretty terrible.

Question around your manifold setup, is it divided or open? Please post up a photo of your hotside. Also cams won't bring on your boost any sooner, I would look at seeing if your VCT is working, without that you're already sacrificing 500~600rpm of spool time.

(bragging rights) I was doing 499hp at the rear on a Mainline dyno with semi-slick tyres. Hit 1.65bar by 4100rpm.

13254873_1752196888370888_1071539108639925081_o.thumb.jpg.1f31e653945e2daa8595dd41e87ba95b.jpg.91adec3ff4f55d63c8406b5ed5377909.jpg

It for sure is absolutely terrible. the flex of 4100rpm full boost is solid my goal is by 4500rpm. As for the hot side I am running the thick cx racing manifold with a precision external wastegate 16psi spring. 3inch downpipe to a resonator and then the muffler. Wastegate is just a 5 inch pipe to atmo. Here's my new theory everybody else feel free to chime in. If my wastegate isn't bolted in as tight as it can be, therefore the fire ring isn't compressed flat on the flange... That could definitely cause some slow spooling issues no? Tomorrow im going to grind down a hex key just for it and crank em down see if anything changes. If this doesn't work then I really am lost. 

IMG-1094.jpg

3 minutes ago, zartroom said:

If my wastegate isn't bolted in as tight as it can be, therefore the fire ring isn't compressed flat on the flange... That could definitely cause some slow spooling issues no?

100% that would be an issue, if that ring isn't flat you're diverting that exhaust energy from the turbo.

  • Like 1
10 minutes ago, Dose Pipe Sutututu said:

100% that would be an issue, if that ring isn't flat you're diverting that exhaust energy from the turbo.

Will update tomorrow. Just tested VCT, clutch in + in gear, solenoid clicks as it should. Also car drives normally out of boost. I almost miss the days when everything was stock

IMG-0895.JPG

  • 3 weeks later...

Long awaited update im sure!!!! f**kin sadly boost leak tested some more, ran it with the smoke machine, and checked torque on exhaust manifold to head, manifold to turbo, and intake manifold to head just to be an asshole and I can't seem to find the cause of the slow spool. Wastegate isn't leaking as far as I can tell. Every time I boost leak test it there is a hissing coming from the q45 tb. If I open the throttle the hissing goes away. Injector seals are fresh so not those either. Chairs are pretty nice thank you 

Set your rev limit to 5000 RPM and a hard fuel cut at 22 psi, find a way to get max pressure on the wastegate spring to keep it closed. If response is any better then you might need to dial in the boost control. Also I hope your wastegate spring is strong, like at least 12-15 psi. Otherwise I think the problem is just your turbo is mismatched to the engine.

1 hour ago, joshuaho96 said:

Set your rev limit to 5000 RPM and a hard fuel cut at 22 psi, find a way to get max pressure on the wastegate spring to keep it closed. If response is any better then you might need to dial in the boost control. Also I hope your wastegate spring is strong, like at least 12-15 psi. Otherwise I think the problem is just your turbo is mismatched to the engine.

That's terrible advice, get it on a dyno and load hold it at a fixed RPM or road speed.

  • Like 2

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...