Advice limits Over 300hp worth it???

[KieranEG6]

Well as it stands I became a 1 bar Mong. Wasn't as impressed as I thought I would be. Sooo... onto the quest for more power.

Have done a good bit of reading around on power limits for most parts but as always muchos interwebs conflicting info. Starting to wonder is it really worth going much over 300hp.

As far as I have gathered of parts that become weak/unsafe links

Stock Clutch becomes weak link at around 300hp , but generally ok below unless thrashed.
Stock Injectors are near max above 300hp. Evo 560's are easy option but need ecu.
Stock Turbo can range from 300hp - 330hp , 350hp maxed if your lucky, but even then it's doubtful to last long.
Stock MAF becomes restrictive around 310-320hp. Not really that unsafe but still strong factor.
Gearbox is fine up to around 370hp But factors of Condition and Usage are big factors. Lower limit of 330hp, higher limit of 400hp.
Engine Bottom end becomes on weaker side above around 350hp.

Upgraded Fuel pump and Mappable ECU are general given prerequisites at either points in my opinion.

So In reality it seems for a real step over 300hp (i.e 320-330hp range) you will need at least Injectors, uprated clutch and MAF. (Intake, exhaust, Fuel pump and ECU as well of course).

Then at which point you are pretty much on the limit of stock turbo.

So anything 330-370hp Ideally you need a bigger turbo, next step up on injectors, then you are almost at the point the Bottom end starts reach its limits so forged motor to keep that safe. But then the gearbox is on edge........

Is over 300hp really worth it???

Me being quite a believer in the old saying "While your in there". Seems there is only 2 real options to me keeping on the safe side.

300hp +/-10 on almost stock everything. 1-1.2Bar, Nistune, 560cc's. Mostly all safe.

Unless the clutch goes then its budget depending. Just upgrade the clutch? And enjoy it at 300-320hp.

or forge the motor while in there as well? and look into a quiaf box? Ready for a bigger turbo when the stock one runs out of puff.

370hp+ Uprated clutch, forged bottom end, bigger turbo, stronger box....

Any input, advice or corrections welcome.

 

[jordan]

Well on my motor the original lump seized when at 280bhp, had all the supporting mods and bits bought new, mapped etc. Ran great for a few months then bang... Saved for a good while and got that Abbey motorsports forged lump, was ran at 355bhp almost ready for the Quaife then fucking booooom!!!

Again, was mapped correctly and using all quality bits but seized and now sat in my garage unloved again.

People rant and rave about power and we are all greedy I know, but I really didnt think much difference in the 70 odd horses, perhaps I was expecting too much but what ever it is under 500ish it aint never gonna be enough is it?!
So if anyone got a decent standard lump for sale please let me know. If you got a good crank for sale, even better. Again, let me know.

My advice is dont get caught up too much in power as you will always want more. Be happy with what you got and go out and actually enjoy it.

Will be interesting to find out one day what caused it to die this time... But its already been nearly a year and still not in any major rush!

 

[campbellju]

Become a 1.2bar mong just fit an AFR gauge and assuming no issues you're done. You might need a new fuel pump but you could get to 320hp. Going above that does need a long list of parts as you believe

 

[KieranEG6]

Fitted an AFR along with the boost controller to be safe. Also running a Walbro 255. Have only pushed it up to 1.1 so far afrs stay around low 11's on Wot through till redline in 3rd and 4th. Next step is ECU an see how she goes. History of the car is it has a fresh clutch and rebuilt box but specs unknown so I'm suspecting stock parts. Mate has a spare set of 560's an I have a spare z32. Was just getting worried about destroying a stock clutch so thought I would evaluate the strength of the rest of the car.

 

[fubar andy]

Gearbox is fine up to around 370hp But factors of Condition and Usage are big factors. Lower limit of 330hp, higher limit of 400hp.

Engine Bottom end becomes on weaker side above around 350hp.

Is over 300hp really worth it???

Gearbox is all dependant on how hard use abuse it.

I've ran around 300bhp for 8 years and the gearbox has been out 11 times...ELEVEN.

Whether that's been bearings, selectors, syncros or stripped gears (3rd and 4th)

Personally there is NO bhp level on these gearboxes as they will go when they want to or wear out; BUT if you must have a level, I personally think that anything over 300bhp will cause some issues down the line.

Bottom end is rated well over 500bhp - proven!



.....and to your last question.

Short answer: NO

Long answer:

NO......because:

I ran 300bhp (approx) for 7 years, whether it was on track or on the road. Mapping and fueling were standard and barring forging the engine in 2007, I never had a problem with it after then.
I ran a topmount intercooler, standard injectors and MAF, and standard turbo.

I never had single engine issue from the car in all those years barring one blown head gasket because I turned up the boost and trial ran a Mines ECU.

Last year I decided to stick in a bigger turbo, massive injectors, a Koyo rad, Forge intercooler (with custom piping and installation) a Nistune and a Z32.

Almost immediately after I'd installed all this equipment and went to map the car at 1.0bar the gearbox grenaded itself on track, chomped 3rd gear and damaged other parts inside the box.

After that I then destroyed the gearbox again at the Isle of Man.

After that I had had an engine rebuild, new pistons from the U.S. Cosworth headgasket, pumps, machine work etc etc

Gearbox out again, due to an issues with some springs and reverse gear

...and currently it's off the road (80 miles on the clock from a rebuild) with a knackered Z32 and currently wait on parts to trial a R35 GTR AFM with my Nistune.

Genuinely some days I fucking hate that car with a passion and wish I'd never bothered looking for more power.

I've never seen over 1.2 bar in that car (EVER) and the new bigger turbo has never been worked to its full potential since it was fitted over a year a ago.

Do I feel it's been worth it? No because I've spent dealing with all the other problems that has come with upping the power, custom making pipe runs for the intercooler, engine rebuilds, gearbox issues and those stupid annoying things the come with it etc etc.

There is a small glimmer that one day it might be completed to around 90% and I'll be happy with that.

Some people might have the money or the patience with upping the power, but both are running short with me and what used to be a great reliable "fun" weekend/track toy has now become a money pit which I'm starting to loath.

One day I'll be driving it around at high boost, mapped up, over taking a GT3 down the back lanes or on a track and then and only then will it be worth it.

...but I'll know that being the old lady that she is she'll break down again and it will be becasue I decided to "up the power" and something will need looking at.

(Not to mention she needs some Botox now *bodywork* as those arches have seen better days)

Up the power if you want, just be aware of the not just the cost for parts, but the hidden costs of everything else.

*sigh* BHP is expensive!

 

[vpulsar]

I've been through this mad quest for power and rebuilt my old R to over 500 bhp, she never broke down once and my quaife box also never gave me any issues but I did have it rebuilt every 25 thousand mils or so, but you know I loved that car the most when it was only 304 bhp running the quaife and motec ecu, she was a beast back then.

But I had to ruin it with all that power that was fun yes but not very practical for what was basically a road car.

Hopefully my new one will be a lot more like the last car before I buggered about with it, I've keep it simple this time. Yes it will be around 400 bhp but with that small fancy gtx turbo it should feel a lot like the old car did, also keep the top mount this time as well.

Rob

 

[KieranEG6]

:shock:

Well now I'm just bursting full of confidence my motor and box is perfectly safe at even 300hp.

 

[Mad]

Here are some useful facts from Ed at Fusion Motorsport -

http://www.fusion-motorsport.co.uk/tech/tuning-guides/tuning-nissan/pulsar-gti-r

 

[Jon Olds]

Rally car is 280hp on a 34mm restrictor and 320 without it. BUT, at >5000rpm in top you can see the first sign of the mixture leaning off on the AFR gauge. Please Croft straight is not longer. So its either injectors maxed, fuel ril pressure dropping etc
300 is plenty fast for my little brain
Jon

 

[fubar andy]

:shock:

Well now I'm just bursting full of confidence my motor and box is perfectly safe at even 300hp.

You'll be fine, your not on track, so 300 is fine for the road. My comment about the gearbox is "general" that any part can break regardless of the bhp, but around 300 on the road will be fine.

As for the engine, (if you want to?) basic rebuild/forge it and add APR rod bolts and you'll be fine for years!

 

[gtir_pimp]

Just out of interest have you had the car on a rolling road to say its 300bhp? I turned the boost up to a bar years ago but on the rollers it only made 265 I think as I had a few other issues. 1 bar doesn't mean it will definitely be 300. I'm sure I had some boost leaks. Sorted that and made 290.

if you get the car mapped to 330 ish then you won't have to turn the boost up so high you max the turbo, for example mine was 333bhp at 1.1 bar!

 

[KieranEG6]

Sorry I didnt mean to sound assuming that I am at 300hp yet from just a boost increase to 1.1B. I was just trying to highlight and evaluate my options, as I was just expecting a bit more from the boost increase, got me thinking will circa 300hp once mapped and sorted be enough to full fill my expectations or will I just keep getting greedy.

So far after summarizing it, If I have a healthy engine, turbo and box that will reliably deliver 300hp, it definitely doesn't seem very worthy of the extra cost and risk to run over the limits of the stock turbo/MAF. In some unlucky cases even that can be quite risky.

If my engine, turbo, both or gearbox shits the bed....

What are the going rates for used forged motors and strengthened box's these days?

 

[The Doc]

Gearbox I.e 2nd hand quaife is £2500 ish dependent on use, engine if you do break a ringland for a set of pistons,gasket set ,rod bolts and mls head gasket (mainbearing and big end bearings are a good idea as well ) £800-1000 in parts and a decent person to build it about £500, being totally honest if you set the car up correctly you will not need those parts.

 

[shroom]

I am finding it hard to justify spending more on my R, I would love a bigger turbo again and a quaife but trying to get my head around the cost is something else.

Although people splash out over 1k on a turbo and thousands on other mods but when it comes to 2k for a quaife its different.

 

[Jon Olds]

Yeah, painful, I know.
But those were two of the many 'must have's' that my rally car got
Jon

 

[The Doc]

There not always must have items a lot of this comes down to previous wear and abuse, 2.5k for a billet competition gearset is small money same as for the engine especially as when you look at the costs to do the same power to performance ratio on other cars, even a quaife for a fiesta is more expensive than the gtir in like for like spec.

 

[Jon Olds]

Cost of early failure in a rally is significant. Entry fees, fuel, hotels, time off work, support crew (LOL!!!!) so some strategic money spent is sometimes a good thing
Jon
Big roller bearing turbo? (difficult to justify, I just wanted it..)

 

[KieranEG6]

Must admit after a bit more number crunching, £4-5k for 400hp proof motor and box. Is not actually that bad. Comparing it to my high comp B20Vtec Civic engine build for a measly 240-250hp NA which is about the same costs for half the power :?. But then again my Turbo Mx5 build seems much cheaper than either .

Cost £ per Pace capability is not so bad in comparison to other cars in the same category or even most other Pace orientated Project cars.

 

[Jon Olds]

Similarly, going from 140 ish to 195 ish on my golf NA has cost me loads, in time as well as parts. 200 to 300 on a sunny is cheap as chips relatively
Jon

 

[Fusion Ed]

Don't be scared by 330bhp. I've tuned so many and they almost NEVER blow gearboxes at this power from my customers at least. Stock rod bolts/engine over 350hp make me nervous. But not 330. The main problem these days is the engines are just old and not enough people think to get a rebuild BEFORE its turns into something catastrophic.

I speak btw as somone who has mapped hundreds of these cars over the last 12 years.