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Hey all, just doing a +t conversion to my 25de R34 coupe. Just hoping someone might be able to help me out with what sort of kw/psi I would be able to push through the de without sending a rod to the moon.

I got a pretty stock kit off a DET with a few upgraded bits.

- All factory piping, intercooler, fuel rail, intake mani and throttle body, exhaust mani, 3" dump through to xforce exhaust.

- High-flowed factory turbo (20psi)

- Bosch 1000cc injectors

- Apexi FC with controller

I know a det can push 500rwhp without upgrading internals but cause of higher comp in the DE I don't know what I should be pushing out of it. Any help would be greatly appreciated, I would still like to daily it but have a fair bit of go if I put the foot down.

Thankyou all

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1 hour ago, R34AC said:

Hey all, just doing a +t conversion to my 25de R34 coupe

Well you have come to the right place! Welcome. Its been done to death previously on this forum. Use the search function.

Rb25 de+t ignition maps.. Boost

just plug that in to search function and choose from 10,000 hits

Edited by Rusty Nuts
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As a serious answer

500rwhp (372kw) is not really that reasonable long term under heavy abuse (track work). I wouldn't push any stock RB that hard unless you're comfortably happy to rebuild/know a guy/have patience for it.

For the non turbo motor, I've heard similar numbers, but given it has higher comp I would just tune the car on 98 (or 93/91 as I suspect you're not Australian), and let knock be your guide.

E85 is good, but regular petrol does act like a bit of a sanity check.

2 hours ago, Kinkstaah said:

As a serious answer

500rwhp (372kw) is not really that reasonable long term under heavy abuse (track work). I wouldn't push any stock RB that hard unless you're comfortably happy to rebuild/know a guy/have patience for it.

For the non turbo motor, I've heard similar numbers, but given it has higher comp I would just tune the car on 98 (or 93/91 as I suspect you're not Australian), and let knock be your guide.

E85 is good, but regular petrol does act like a bit of a sanity check.

Im in QLD Australia, the previous owner of the kit only ran it on e85 and it would still be my daily, ive just heard so many different numbers thrown around that I really don't know how far to go with a tune without blowing something up, I know I have the parts capable of pushing 400+ but I'm not sure if the internals could keep up with it.

33 minutes ago, R34AC said:

just heard so many different numbers thrown around that I really don't know how far to go with a tune without blowing something up, I

That's because there are a wild amount of variables, so the actual number doesn't exist. How would it?

2 minutes ago, Ben C34 said:

That's because there are a wild amount of variables, so the actual number doesn't exist. How would it?

Im not after a specific number im just after a generally safe area where the internals won't be under so much pressure they break but also has some go if I wanted to put the foot down, I know it can make 400 but im not sure if 400 is safe because de comp is so high. I have the supporting power parts but if my internals can't do more than 350 on 10psi reliably then I don't know what I can put through it. Some people have said it'll do 400 on 20psi while others have said no more than 230 on 7psi. I never thrash my car as to me it's way too precious to me lol. I've just always had a large margin between what people say is good for it, that's why im hoping someone who has done it before would be able to tell me what I can and can't do with it cause I'm still learning all this sort of stuff and need a bit of help.

2 minutes ago, Rusty Nuts said:

I was serious Greg, trying to encourage self education before asking the universe.

I do appreciate the help, I just can't afford to buy a whole new engine if I go with a handful of people that say blast 50million psi through it. I've done some googling but again it's all very different for everyone and I'm not someone to flog the engine, it gets me to / from work and cruising through town on the weekends.

2 hours ago, Rusty Nuts said:

I was serious Greg, trying to encourage self education before asking the universe.

Sorry, I didn't mean to imply you weren't serious

That said

Searching the internet does lead you to believe 370kw is "safe, for years bro" and it is not always that case, or that simple. People's use cases vary so very drastically. Honestly NA+T I'd shoot for something like 240kw with a manual gearbox and highflow OEM looking turbo and be like yep go enjoy car.

However if you can't afford to live without the car/can't afford a rebuild/don't have another motor then Step 1, 2, 3, 4, and 5, is obtain a backup car/work towards an engine ready to go. 

Have a backup plan. These are not cars you can drop off at your local ultratune and expect a broken motor to be replaced within a week.

2 hours ago, Kinkstaah said:

Searching the internet does lead you to believe 370kw is "safe, for years bro"

Hence why I suggested the search on this forum, go back ten years and the crazy ideas were getting shot down. Go back three months and some new ideas and old were punted around. Its all in the archive here, plus you get to read GTSBoy's remarks all over again ( Warning: these remarks are intended to offend the "can I put an XR6 turbo on my N/A, will the gearbox handle 800hp crowd" )

Just remembered the member to check out is DatsunBanana he drives an R34de+t auto and is keen on the subject, also check out 666Dan's legendary thread.  

How to turbo your N/A

By 666DAN, February 2, 2004 in Naturally Aspirated Performance

Edited by Rusty Nuts
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