Jump to content
SAU Community

New Turbo Set Up Gt35R. How Much Power Before I Should Upgrade From Stock Exhaust Manifold?


Recommended Posts

i see a lot of people on here are running the stock cast exhaust manifold with a external wastegate welded on. im about to go that route but i was wondering at what power will this start to hold me back. my set up is going to be a stock internal rb25 with a gt3582r 740cc injectors and nistune. i would like to make between 400-450whp just making sure that will be possible with that manifold. i have a greddy intake manifold q45 tb. 3.5 inch straight pipe exhaust. my motor is in very good shape, great compression, everything has been inspected and it has been run for a year with the stock setup and made great power on the stock turbo but its time to upgrade. i don;t think its really necessary for me to go with a tublar manifold untill i build the motor and look to squeeze more power out of it. but since it is only in a tiny s13 400 is going to be a lot. looking to run probably around 16psi on the turbo, if i have to i may put a set of some less aggressive cams in or get my stock ones reground. any ideas people have for me feel free to throw out. i undertstand the gt35r is probably a little overkill for my power goals. but i got it for a great price and i would like to have the room to grow in the future. thanks for looking and for any help!

Gt35 really is too big for the standard exhaust manifold, a 3076 would have been a better choice imo.

But as you said you will want more later so save up for an ETM or 6 boost manifold

well heres the other thing. i also have one of those manifolds that i've seen like 10 different companys names on but its really just a cheap ss tublar manifold with a t3 flange and a bottom mount 38mm tial wg flange. prob is like most turbos the clearance isn;t so well. the compressor cover hits the valve cover just slightly. but im unsure about how anyone has modified it to work. it also seems that the turbo sits very high and im worried about hood clearance... if i absolutely have to i will go with the rawbrokerage manifold that just came out.

Forget the cheap stainless crap.

6-boost or ETM or whoever else is doing custom manifolds will be able to build one with plenty of bonnet clearence.

eg I had a TD07S on a 6 boost manifold on an RB25/30 and it cleared the bonnet fine in my R33

stock manifold is too small, most setups have issues around the 300rwkw mark.

given a GT35 will make around 360-380 on most setups, thats well above

Forget the cheap stainless crap.

6-boost or ETM or whoever else is doing custom manifolds will be able to build one with plenty of bonnet clearence.

eg I had a TD07S on a 6 boost manifold on an RB25/30 and it cleared the bonnet fine in my R33

like anything cheap if done correctly it can work.

Just dont go bolting it on and expecting it 2 do its job

You will probably spend more time and money stuffing around putting it on the standard manifold than if you just bit the bullet and went a decent high mount manifold...

Plus then you are not going to have restrictions on power!

Also a GT35R on a RB25 on 16psi will be a dog :(

Better to use the stock manifold than a cheap stainless one that cracks. Run the external w/g off the turbine and save up for a 6boost or similar later. let us know how it goes with the stock manifold.

post-49463-0-02856300-1292980236_thumb.jpg

^^ thank you best reply so far. i guess people are missing the point. its not that i cant afford the 6 boost or a better tublar manifold i was asking which was better. i know the 35r is gonna be a dog, but its gonna be better than the stock turbo. my set up is going to be tuned with nistune and im not building the motor yet. i have too much other stuff to do to the car this year so its just not in the budget. its not like this is going to be the permanent set up just wondering which would be the best way to go about it at the moment.

My opinion is to do the turbo swap properly.. go the decent high mount manifold and set it up for that otherwise you'll be dicking around with cooler and dump piping again when it comes time to put a proper manifold on.

well the other thing is i can/have fabricated everything on the car i don;t care if i have to tweak a down pipe later on. and i also can modify the stock manifold for the price of the wastegate flange and pipe for it. but idk everyone is raving about aftermarket manifold i'll see what i can find, 6 boost seems hard to find in the US

well the other thing is i can/have fabricated everything on the car i don;t care if i have to tweak a down pipe later on. and i also can modify the stock manifold for the price of the wastegate flange and pipe for it. but idk everyone is raving about aftermarket manifold i'll see what i can find, 6 boost seems hard to find in the US

Plus you have to factor in the costs of...

New oil and water lines

New intake pipe

New dump

External Wastegate

Spacer for the turbo

Second Gasket for the spacer

Screamer pipe

Plus I would actually debate that a GT35R on 16psi would be better than a stock turbo

What exhaust housing do you have on the GT35?

0.63 housing will give you good response and up to 300rwkw. 0.82 will have some lag but will be great once you build the engine and decide to push things. 1.06 will be VERY laggy and not recommended.

What you could do is throw the 0.63 on while the engine is standard, then upgrade to a 0.82 when you build the engine.

Brad, I would argue for the GTX3076 over the GTX3071 as he plans to build an engine later on.

well the other thing is i can/have fabricated everything on the car i don;t care if i have to tweak a down pipe later on. and i also can modify the stock manifold for the price of the wastegate flange and pipe for it. but idk everyone is raving about aftermarket manifold i'll see what i can find, 6 boost seems hard to find in the US

Well if you are in the US you might as well buy one from Sinco Customs (as per my pic above):

http://www.sincocustoms.co.nz/

If you tell him what car and what engine he will be able to make one that will fit for around NZ$1500. (Aussie dollar is quite strong at the moment so Sinco from New Zealand probably better value for you than 6boost from Australia).

Good response compared to what though a T04Z?

r33cruiser, on 28 May 2010, 10:36 PM, said:

full boost (16psi) at 3600-3800. Pulls HARD, all the way to 7500rpm.

No more than ~200rpm difference between a GT30 0.82 and a GT35 0.63 on a stock RB25.

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

    • Can perhaps see how the R33 appreciators would think so.  
    • Thanks, I removed the fuse and the relay from the car and made my own circuit with them to test them with a test bulb.  I will look for the wiring diagram and go from there.
    • Jdm DC2R is also nice for a FF car compared to the regular hatches of the time.
    • Now that the break-in period for both clutch and transmission is nearly over I'd like to give some tips before I forget about everything that happened, also for anyone searching up how to do this job in the future: You will need at least 6 ton jack stands at full extension. I would go as far as to say maybe consider 12 ton jack stands because the height of the transmission + the Harbor Freight hydraulic platform-style transmission jack was enough that it was an absolute PITA getting the transmission out from under the car and back in. The top edge of the bellhousing wants to contact the subframe and oil pan and if you're doing this on the floor forget about trying to lift this transmission off the ground and onto a transmission jack from under the car. Also do not try to use a scissor jack transmission lift. You have to rotate the damn thing in-place on the transmission jack which is hard enough with an adjustable platform and a transmission cradle that will mostly keep the transmission from rolling off the jack but on a scissor lift with a tiny non-adjustable platform? Forget it. Use penetrating oil on the driveshaft bolts. I highly recommend getting a thin 6 point combination (box end + open end) wrench for both the rear driveshaft and front driveshaft and a wrench extension. These bolts are on tight with very little space to work with and those two things together made a massive difference. Even a high torque impact wrench is just the wrong tool for the job here and didn't do what I needed it to do. If your starter bolts aren't seized in place for whatever reason you can in fact snake in a 3/8 inch ratchet + 6 point standard chrome socket up in there and "just" remove the bolts for the starter. Or at least I could. It is entirely by feel, you can barely fit it in, you can barely turn the stupid ratchet, but it is possible. Pull the front pipe/downpipe before you attempt to remove the transmission. In theory you don't have to, in practice just do it.  When pulling the transmission on the way out you don't have to undo all the bolts holding the rear driveshaft to the chassis like the center support bearing and the rear tunnel reinforcement bar but putting the transmission back in I highly recommend doing this because it will let you raise the transmission without constantly dealing with the driveshaft interfering in one way or another. I undid the bottom of the engine mount but I honestly don't know that it helped anything. If you do this make sure you put a towel on the back of the valve cover to keep the engine from smashing all the pipes on the firewall. Once the transmission has been pulled back far enough to clear the dowels you need to twist it in place clockwise if you're sitting behind the transmission. This will rotate the starter down towards the ground. The starter bump seems like it might clear if you twist the transmission the other way but it definitely won't. I have scraped the shit out of my transmission tunnel trying so learn from my mistake. You will need a center punch and an appropriate size drill bit and screw to pull the rear main seal. Then use vice grips and preferably a slide hammer attachment for those vice grips to yank the seal out. Do not let the drill or screw contact any part of the crank and clean the engine carefully after removing the seal to avoid getting metal fragments into the engine. I used a Slide Hammer and Bearing Puller Set, 5 Piece from Harbor Freight to pull the old pilot bearing. The "wet paper towel" trick sucked and just got dirty clutch water everywhere. Buy the tool or borrow it from a friend and save yourself the pain. It comes right out. Mine was very worn compared to the new one and it was starting to show cracks. Soak it in engine oil for a day in case yours has lost all of the oil to the plastic bag it comes in. You may be tempted to get the Nismo aftermarket pilot bearing but local mechanics have told me that they fail prematurely and if they do fail they do far more damage than a failed OEM pilot bushing. I mentioned this before but the Super Coppermix Twin clutch friction disks are in fact directional. The subtle coning of the fingers in both cases should be facing towards the center of the hub. So the coning on the rearmost disk closest to the pressure plate should go towards the engine, and the one closest to the flywheel should be flipped the other way. Otherwise when you torque down the pressure plate it will be warped and if you attempt to drive it like this it will make a very nasty grinding noise. Also, there is in fact an orientation to the washers for the pressure plate if you don't want to damage the anodizing. Rounded side of the washer faces the pressure plate. The flat side faces the bolt head. Pulling the transmission from the transfer case you need to be extremely careful with the shift cover plate. This part is discontinued. Try your best to avoid damaging the mating surfaces or breaking the pry points. I used a dead blow rubber hammer after removing the bolts to smack it sideways to slide it off the RTV the previous mechanic applied. I recommend using gasket dressing on the OEM paper gasket to try and keep the ATF from leaking out of that surface which seems to be a perpetual problem. Undoing the shifter rod end is an absolute PITA. Get a set of roll pin punches. Those are mandatory for this. Also I strongly, strongly recommend getting a palm nailer that will fit your roll pin punch. Also, put a clean (emphasis on clean) towel wrapped around the back end of the roll pin to keep it from shooting into the transfer case so you can spend a good hour or two with a magnet on a stick getting it out. Do not damage the shifter rod end either because those are discontinued as well. Do not use aftermarket flywheel bolts. Or if you do, make sure they are exactly the same dimensions as OEM before you go to install them. I have seen people mention that they got the wrong bolts and it meant having to do the job again. High torque impact wrench makes removal easy. I used some combination of a pry bar and flathead screwdriver to keep the flywheel from turning but consider just buying a proper flywheel lock instead. Just buy the OS Giken clutch alignment tool from RHDJapan. I hated the plastic alignment tool and you will never be confident this thing will work as intended. Don't forget to install the Nismo provided clutch fork boot. Otherwise it will make unearthly noises when you press the clutch pedal as it says on the little installation sheet in Japanese. Also, on both initial disassembly and assembly you must follow torque sequence for the pressure plate bolts. For some reason the Nismo directions tell you to put in the smaller 3 bolts last. I would not do this. Fully insert and thread those bolts to the end first, then tighten the other larger pressure plate bolts according to torque sequence. Then at the end you can also torque these 3 smaller bolts. Doing it the other way can cause these bolts to bind and the whole thing won't fit as it should. Hope this helps someone out there.
×
×
  • Create New...