R34 Gtr Mods Opinions

[livewire]

Hi everyone.

This might seem like a silly topic but was just after some input from some more experienced GTR owners/modifiers/tuners as i have just purchased most of the stuff im about to have put on my R34 GTR and have tuned so after a few opinions on an estimate of what sort of power i can realistically expect to see or be happy with. Mods will be as follows:

N1 GT Le Mans group A turbos (freshly rebuilt)

750cc siemens injectors

Apexi Power Fc

nismo air flow meters

walbro in tank fuel pump

adjustable cam gears

3" dump pipe back apexi exhaust

HKS electronic boost controller

(keeping standard air box)

Any thoughts would be greatly appreciated

Thanks

[paulr33]

330awkw id guess

the le mans turbos might be laggy mofo's though ?

the pump is your achiellies heel

if that pump cant keep up cos its walbro nasty -> good bye BNR34 RB26 and rebuild light is on

be wary and double check it is legit and can flow the fuel you require, dont assume, check.

the main thing to check is that your fuel pressure doesnt bleed away under heavy load and on full song.

[R31Nismoid]

Most of the parts really won't make a difference - the key part is the turbo and exhaust in your setup.

3" is too small, 3.5" would be more ideal/suited.

And the LeMans 581 turbos are incredibly laggy for the power (~330-340rwkw), as they are a design from the 1980's with nothing but top end in mind.

The Garrett -9 would make similar power and come on around 1,000rpm sooner from all reports.

I would look at selling the 581 and putting on different turbos if it were my choice. Turbos are what makes a setup, so spend the money there IMO.

As Paul said, I wouldn't use a Walbro either. Bad experience with one 7 years ago, never going there again.

[livewire]

Thanks for the feedback.

Thats a bit of a shame cause ive just about got everything ready to go lol. I might see how i go with the parts ive got and can always get tuners opinion on where to go from there. As for the walbro pump, i bought it from Justjap in Sydney who said the in-tank walbro flows really well. I had been told the walbro wouldnt be sufficient and to get the bosch 044 0r 040? called Justjap and they were happy for me to exchange it but said the in-tank walbro actually flows better so might have to ask the tuner that one.

[R31Nismoid]

Only issue with changing turbos later is $1,000+, hence i really think you should sell and buy better performaning ones.

If you had a 18k 32GTR, were trying to save cash then i guess you could pass it by... But you have a 34GTR mate that's cost id say around 45-55k. Another 800-1200 for better turbos now is much more important and justified.

1,000rpm better response for the cost is the best money you'll ever spend.

A 34 is also heavy making lag and delay between gears all the worse.

Are you in Vic? Happy to take you for a spin in mine if you are.

[Thelen]

If you don't plan to increase power any further, a single 044/040 will be fine. Or if you plan to track it/more power, you'll need a proper surge + dual pump setup.

Walbro is OK, I got plenty of friends who use them, anecdotes aside though Bosche are generally better.

[livewire]

Thanks for the advice R31nismoid. I read up on the le mans turbos and the guy I bought them off did say they would be slightly laggier than say the -5's which I'm lead to believe are very similar in size etc but the difference would be hardly noticable if at all as they aren't ball bearing. I did get them pretty cheap and haven't been used since being rebuilt so pretty much new. I'll give tin

[livewire]

Oops, accidentally pressed send. I'll give them a go and I guess I'll be the guinnea pig for le mans group A's on an R34 lol. If worst comes to worst I'll through the factory ones back on lol.

[livewire]

Oh and I'm in n.s.w Unfortunatly nismoid otherwise I would love to have gone for a drive.

[R31Nismoid]

the guy I bought them off did say they would be slightly laggier than say the -5's which I'm lead to believe are very similar in size etc but the difference would be hardly noticable if at all

Well that statement comes as no surprise given whoever it was, was trying to sell you something at the end of the day

You'll notice it mate, no doubt about that one.

If they are newly rebuilt, you could sell them for what, $800-$1000 - then a set of -9s would only cost you an addional $1400

That'll be less than the cost of swapping the turbos out later and the retune associated.

[Beer Baron]

Thanks for the feedback.

Thats a bit of a shame cause ive just about got everything ready to go lol. I might see how i go with the parts ive got and can always get tuners opinion on where to go from there. As for the walbro pump, i bought it from Justjap in Sydney who said the in-tank walbro flows really well. I had been told the walbro wouldnt be sufficient and to get the bosch 044 0r 040? called Justjap and they were happy for me to exchange it but said the in-tank walbro actually flows better so might have to ask the tuner that one.

if justjap are still happy for you to exchange your pump I would exchange it for a nismo pump. it's a much better match for your 750cc injectors and are super reliable and very easy to install (you could do it yourself or any workshop should do it in 20mins or less).

seriously. the fuel pump is the heart of your car. if it fails, you car fails..... nismo pumps are expensive but flow exactly what they claim to and are super reliable.

[Beer Baron]

i agree. given the labour costs involved in turbo swaps I would probably sell the LMS turbs and get a set of HKS GT-SS or some garret equivelants, or even some R34 N1s. they are all great options (and all very similar).

[GD2ILA]

to op you have a BNR34, honestly you should do things right the first time and not have to change the turbos later on it's just better planning. spend a little bit more now and takes a little longer but all worth it in the end as you know you did it properly and be more happy with the outcome.

[choyda]

As an owner of a 34 with -5's, they aren't great for the street on the stock 2.6L so if the LeMans are worse, holy crap.

[R31Nismoid]

^ exactly my point lol.

[trick]

As an owner of a 34 with -5's, they aren't great for the street on the stock 2.6L so if the LeMans are worse, holy crap.

i have -5s on my GTR, mine are great for the street.

just put on some custom twin turbo pipes and the boost comes on even earlier too.

id go for the -5s for sure and the nismo pump. you need reliability at the end of the day.

motors should be built once

[livewire]

Thanks guys... I now feel like I've completely wasted my money Haha.

[Beer Baron]

not yet you haven't mate. easy to re-sell the turbos since you haven't fitted them. and hopefully just jap will give you credit to the value of the walbro towards a nismo pump. otherwise just re-sell the walbro. I have a new 34 GTR nismo pump here somewhere you could have for cost/wholesale.

you're on the right track just need to refine the choices a bit. I have owned a couple of GTRS with 2530s (similar to -5s) and agree they are probably not the perfect choice for a 26 road car. on my Jun 2.7 they are a bit better but GT-SS or 34 N1s will make a better street set-up for you.

seriously, on a road car with some GT-SS or 34N1s and the other gear you have you'll end up with a nice 300-300kw atw and it will be FAST!

[R31Nismoid]

100% agree with the above. Certainly not a waste of money yet

[choyda]

i have -5s on my GTR, mine are great for the street.

just put on some custom twin turbo pipes and the boost comes on even earlier too.

id go for the -5s for sure and the nismo pump. you need reliability at the end of the day.

motors should be built once

Hi,

Don't suppose you can pm me a dyno sheet and let me know what else you've done. It's not that I don't believe you, I just thought I'd done everything to cut the lag before opening the engine.