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he guys got 2 questions for you all regarding cams. I have a full built bottom end in my gtr with cp pistons, eagle rod's ect and all the other good gear and i have n1 turbos. Here is the thing the bloke that built the motor and the prevouse owner decided to leave the cams and head stock and it hasnt been retuned since the build. My question is What sort of power and responce can i expect from the stock cams at a maxium relieable power. With all other supporting mods like injectors fuel pump pfc ect. And what is invlove in fitting say 260 degree 9.15mm lift pon cams like do i have to replace the valve springs and replace the lifters or can i get away with springs and reshiming the lifters in it and will it be worth it to spend the extra coin to do this like will it improve responce on the street.

And question 2 how much power / flow can the stock dump pipes handle as the exhuast that is on the car currently is 2.5 inch front pipes high flow cat and 3 inch cat back. and once again will this make a huge differance with the n1 turbos or will they do untill both turbo's upgraded

cheers scottie

he guys got 2 questions for you all regarding cams. I have a full built bottom end in my gtr with cp pistons, eagle rod's ect and all the other good gear and i have n1 turbos. Here is the thing the bloke that built the motor and the prevouse owner decided to leave the cams and head stock and it hasnt been retuned since the build. My question is What sort of power and responce can i expect from the stock cams at a maxium relieable power. With all other supporting mods like injectors fuel pump pfc ect. And what is invlove in fitting say 260 degree 9.15mm lift pon cams like do i have to replace the valve springs and replace the lifters or can i get away with springs and reshiming the lifters in it and will it be worth it to spend the extra coin to do this like will it improve responce on the street.

And question 2 how much power / flow can the stock dump pipes handle as the exhuast that is on the car currently is 2.5 inch front pipes high flow cat and 3 inch cat back. and once again will this make a huge differance with the n1 turbos or will they do untill both turbo's upgraded

cheers scottie

leave the cams...but upgrade the dumps. A set of camgears or even just one on the exhaust side would be the best way to get the most from the stock cams with N1's and a stock head.

he guys got 2 questions for you all regarding cams. I have a full built bottom end in my gtr with cp pistons, eagle rod's ect and all the other good gear and i have n1 turbos. Here is the thing the bloke that built the motor and the prevouse owner decided to leave the cams and head stock and it hasnt been retuned since the build. My question is What sort of power and responce can i expect from the stock cams at a maxium relieable power. With all other supporting mods like injectors fuel pump pfc ect. And what is invlove in fitting say 260 degree 9.15mm lift pon cams like do i have to replace the valve springs and replace the lifters or can i get away with springs and reshiming the lifters in it and will it be worth it to spend the extra coin to do this like will it improve responce on the street.

And question 2 how much power / flow can the stock dump pipes handle as the exhuast that is on the car currently is 2.5 inch front pipes high flow cat and 3 inch cat back. and once again will this make a huge differance with the n1 turbos or will they do untill both turbo's upgraded

cheers scottie

Hey mate,

In regards to the stock dump pipes in my opinion i would be waiting till i got the new turbos before worrying about them as they are a turbo out job anyway. So this money can be save and put towards more power :cool:. As for the cams i would be doing the turbos before the cams as the N1s are still only good for mid range power where as you have the set up and ablity to run much more boost. With more psi this would far out weigh the cams in terms of performance. Depending on what turbos you are running you can get some good power out of your engine while still having good street drivablity.

With the cams, if a set of after market cam gears haven't been fitted i would suggest you do this, or do the cams and gears as a package. (have a look on Nengun Co. for good prices. Found they're the best so far.) This also tells you what you need to do inorder to run the cams you wish to run. Just remember the bigger the cams, the higher up in the rpm they will work more effectively and gain more power but loose some bottom end. Hope this helps you mate. Any questions fell free to contact me :P

Matt

P.s, this is only my opinion and is not gospel, just what i have found in terms of my car. There are alot more experienced people out there but i hope i have helped. also, swiper the fox = god to me ha ha helped me out heaps, Thanks again Paul

Edited by 32vspec2gtr

Hmm thats what i was thinking but i didnt know if the adjustable cam gears could give the adjustments that are needed as far as the dumps go for off the shelf items like brand names or go to my local exhaust shop and get some customs i have seem some awesome work come from the bloke i have used for years

cheers matt every ones advice and experience is welcome i may be a tradey and can do the work myself but when i comes down to the performance side of things my knowledge is pretty shit and spec's that suit but that comes with working for a dealership and not beening exposed to this side of things

cheers matt every ones advice and experience is welcome i may be a tradey and can do the work myself but when i comes down to the performance side of things my knowledge is pretty shit and spec's that suit but that comes with working for a dealership and not beening exposed to this side of things

Ha ha yeah i know what thats like!!! I'm a diesel fitter by trade and i work with a mate at the drags on a 6 sec turbo 350 altered, but is totally different to this engine so hard to compare lol

With the cam gears, big cams aren't as important as on a NA car as the pressure fills the cylinder more as compared to just the suction of the engine, so unless your hunting for big power, and i mean big there really isn't much point. Its more the cylinder overlap that is important as you want to trap the boost rather than blowing it all out the exhaust. Thats my understanding in it anyway. Could be wrong. So yeah, if your going to do the cams you should look at probably going something fairly meaty and upgrading the springs, etc and doing some head work to get the most out of them.

The dumps can be used to make 300kws yes, but by upgrading these you will get better spool time and therefore better driveablity and makes it easier to get to the horsepower, etc. Also your turbos, etc will run cooler thanks to being able to breather better

Cheers

Edited by 32vspec2gtr
The dumps can be used to make 300kws yes, but by upgrading these you will get better spool time and therefore better driveablity and makes it easier to get to the horsepower, etc. Also your turbos, etc will run cooler thanks to being able to breather better

Cheers

Sorry, i went from Trust split dumps, back to factory...

There was no difference in before/after. Car was absolutely identical. Still made 280rwkw, same spool, same response, same boost and so on.

So this unfortunately disproves that.

So youre saying everyone making around 300rwkw is wasting their money putting dump pipes on their cars?

Maybe your 'split dumps' were just plain shite?

To the OP, I just bought a set of 260/260 9.15 Tomei cams...im running 34 N1s (-7s)...if/when I get around to installing them and the 750cc Injectors will let you know the results...

Edited by NSNPWR
The Trust dumps certainly dont look shite! In fact they look rather awesome.

Yeah i have those, even if they do nothing i still get to touch myself at night about how awesome they look, oh the welds :cheers:

That is exactly what i am saying... I'm sure that was pretty clear though?

Just wanted to be doubley sure.....

One result, namely yours, doesnt make it fact that theres no gains to be had from upgrading the dump pipes...infact, your 'evidence' would contradict the majority of results out there...

Be interested to know exhaust temps....what exactly made you go back to the stock dumps?

Ride height. Trust dumps as you can see hang very low, and there is a 2nd part where the two pipes merge into one. Which hangs even lower again (where the flex pipe is)

As the RB26 sites very low in a HR31, i was around 70mm, so had to take the dumps off and use something else.

I was told by a rather well known workshop that they will be perfectly fine for GT-SS's (stock dumps) based on some testing that had been done. So on they went.

So that then gave me around 110-120mm ride height from memory as a lowest point so problem solved.

I would have left them on there is there was no issue with it all, but having changed them and seen no detrimental impact - if i knew that in the first place i never would have purchased them :cheers:

Fair enough then...might put a few exhaust shops and manufacturers out of business....Lol.

This does not mean they would not be beneficial at higher power levels. Plus exhaust shops dont just sell dump pipes haha

Just because someone makes a product doesnt mean that it has to work for everyone with every setup.

Out of interest how about the dump pipes on an RB25DET? What power level do they start becoming beneficial?

Fair enough then...might put a few exhaust shops and manufacturers out of business....Lol.

It's like a lot of products out there though. Just because someone is selling something, does not mean you actually need it :cheers:

Lots of Nissan OEM stuff is actually exceptionally good.

Sometimes however the issue lies with purchasing it from Nissan... sometimes aftermarket is cheaper in terms of replacement costs and so on.

Ride height. Trust dumps as you can see hang very low, and there is a 2nd part where the two pipes merge into one. Which hangs even lower again (where the flex pipe is)

As the RB26 sites very low in a HR31, i was around 70mm, so had to take the dumps off and use something else.

I was told by a rather well known workshop that they will be perfectly fine for GT-SS's (stock dumps) based on some testing that had been done. So on they went.

So that then gave me around 110-120mm ride height from memory as a lowest point so problem solved.

I would have left them on there is there was no issue with it all, but having changed them and seen no detrimental impact - if i knew that in the first place i never would have purchased them :)

The engine you are using maybe a later model of gtr engine. The 32 dump pipes are know for been restrictive and therefore restricting the boost response, etc. I found with my gtr that the difference with the dumps is very good compared to a mates who only has a 3' exhaust from the front pipes back due to not wanting to remove the turbos. My exhaust runs cooler and also creates a couple of pound more boost. This is only from what i have seen. The Gtss turbos are also designed for response rather than outright power so do not need as much to make them spool up. The ball bearings also help this. So really it depends on the size of turbo in which he is going to be installing.

This is just what i have seen in my experience. Not saying that you are wrong but yeah, very interesting to know that they didn't do too much for your set up

cheers guys well i am looking keeping the n1's on for quite awhile ey as far as dumps are concerned i would love to have the cash to throw a sett of good named trusts or other brand name but. Looking at the xforce dumps they dont look to bad without me holding them in my hands to look at compared to the big names and they are half the price and i was going to get my exhuast shop to make me up a pretty front pipe as well

cheers guys well i am looking keeping the n1's on for quite awhile ey as far as dumps are concerned i would love to have the cash to throw a sett of good named trusts or other brand name but. Looking at the xforce dumps they dont look to bad without me holding them in my hands to look at compared to the big names and they are half the price and i was going to get my exhuast shop to make me up a pretty front pipe as well

If your on a budget mate, try looking on the for sale sections as there are a fair few goodies around that can be picked up cheap. Or try boost cruisings website sale section.

:)

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