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Discussion Starter · #1 ·
if taking the ZR TD over 160bhp, ive read it will need a new gear box?

im wondering where you would purchase this and how much it would be?

and also after buying it, could a standard garage fit this for you or would you have to see a specialist?

chiers guys:mario:
 

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Yeah, there are a few issues with the gearbox. Anything over 150 bhp, then you are starting to push its limit. Its not the bhp, but the torque that kills it.

The problem with gearbox is the bearings as they have plastic casings and you would need to uprate them to stainless steel. You are also talking about an uprated clutch.

Money wise, hmm 160 bhp would really cost a minimum of £700 and this is serious shopping around.

I thought this guy in Norfolk offered a rather good price.

http://www.rovertech.net/forum/viewtopic.php?p=678678&sid=507159b43e7911830331c07805d90ffa

Most mechanics wont touch the gearbox. I called around local and I got a quote for £325 just for the fitting.

Intelligent tunning will do the rebuild £150 and the fitting £150, but they are not the cheapest either.
 

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Discussion Starter · #3 ·
thanks alot drevo, i supose £300 altogether from intelligent tuning isnt bad (is that for the whole lot, gearbox and clutch??)

also mate, ive heard about these sdi injectors, where will i find them, what price and will a mechanic fit those?

one last question lol.. with the derv when tuning, can you fit things like fast road cams and a better throttle body??

cheers pal
 

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your my guinnypig mate this goes well i think all be following just keep the thread updated and if your going for the 160 bhp or above good luck hope it goes well !!!!
 

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thanks alot drevo, i supose £300 altogether from intelligent tuning isnt bad (is that for the whole lot, gearbox and clutch??)

also mate, ive heard about these sdi injectors, where will i find them, what price and will a mechanic fit those?

one last question lol.. with the derv when tuning, can you fit things like fast road cams and a better throttle body??

cheers pal

No, that is the labor for the gearbox. The bearings are around £180 and a clutch is £200. It is really expensive and a lot people stay below 150 bhp.

I might have a nice set of sdi injectors up for sale on the weekend. I need to make a decision.
 

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sorry if am spamming mate,

whats the cost diffrence and whats involved with the 150bhp
 

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Discussion Starter · #7 ·
i'll be honest..im looking for 180bhp+..and no i'm not stupid...you only live once hahaha..just imagine it!!!:weirdo::boxing::happy2::fishing::pope::slap:
 

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that would be impresive mate keep me informed
 

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The minimum break down to 150 bhp

Get your car in excellent condition
Clean air intake system
Check cam belts
Service
Check MAF
Brakes
Bushings


Air in
Open cone filter £50-100
Increase boost pressure to 19 psi (Boost gauge £25)

Air out
De cat (£40) can gut (free)
Back box (£150-£200) Not sure if necessary, can gut

Increase fuel
Remap (£200-300)
Sdi Injectors (£60-130)
 

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Discussion Starter · #11 ·
ok so after taking into consideration the above list to get the derv up to 150, so lets talk about what happens after 150bhp!!

lets say we get the upgraded gearbox and clutch, what sorta tuning and upgrading can we do to get up to 180-200bhp!

im really interested in what is possible after 150bhp! if we had £1500 to spend what would we do next??

:yoji::police::snorkle::rofl::bow::lttd::fish:
 

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ok so after taking into consideration the above list to get the derv up to 150, so lets talk about what happens after 150bhp!!

lets say we get the upgraded gearbox and clutch, what sorta tuning and upgrading can we do to get up to 180-200bhp!

im really interested in what is possible after 150bhp! if we had £1500 to spend what would we do next??

:yoji::police::snorkle::rofl::bow::lttd::fish:

I think 180 bhp is rather unrealistic. Mad's car is about that and it is the fastest l series that I know about. He does go to a lot of lengths to get it there, it is not a matter of strapping on a few parts, it all takes a lot of time.

The problem with gearbox is it is rated upto 240 Nm of torque and that is what the ZR 115 is comes standard. Any increases brings it over that limit. However, the torque has a rather sharp peak around 2300 rpms. If you flatten out the torque curve by increasing the torque in the mid to high rev range, than you are not increasing the max torque.

Yeah, £1500 is a good budget. I would do the above list, uprate the brakes and see what else needs doing, e.g. suspension
 

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well a upgraded clutch will be around 250 for a kevlar unit. Upgrading the bearings in the box is £170 + labour and then i would think about putting in a limited slip diff while your at it. You have a few options with this.

at 150 bhp ull be looking around the 250ft/lb mark, depending on intercooler, turbo, etc.

at the minute most guys are getting away with std clutchs and gearboxs running around 145 - 150bhp, but like drevo says, u need to get the remap so it makes the power delivery abit kinder to the transmission.

a kevlar clutch is rated to 350ft/lb but i dont think anyone knows wat the gearbox will take.
 

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Intelligent tunning said that they have successfully drag raced a 550 bhp car with a PG1 gearbox and uprated bearings.
 
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