Jump to content
Sign in to follow this  
lookingforboost

WRX front mount or no front mount?

Recommended Posts

Ok i know its a kinda silly question but i have had so many confilicting answers?

 

my mum has a MY99 WRX with 3" turbo back from hitech system hybrid VF23 turbo running 15psi turbosmart bov plumbed back and a hks filter and unichip computer.

 

all the internals have been rebuilt to STi spec and is getting high flow extractors and turbo up pipe fitted soon but want to know about the intercooler before it goes in for a tune.

 

but what is better running a frount mount intercooler or a larger top mount? i know the piping is a lot longer in the front mount setup? but the topmount is prone to heat soak when not moving?

 

the car runs great but all power hits hard at about 3900-4000 rpm and she dosent want it to lag anymore than that and all the answers have been will be worse? change it dont change it??GRR

 

so anyone with this model REX can shead some light that would be great.

 

Thanks guys

Share this post


Link to post
Share on other sites

I'd say a front mount would be better because obviously you've got less restrictions in terms of room so you can get a bigger cooler which means better cooling due to more surface area (more cool air hitting the cooler)

Share this post


Link to post
Share on other sites
I'd say a front mount would be better because obviously you've got less restrictions in terms of room so you can get a bigger cooler which means better cooling due to more surface area (more cool air hitting the cooler)

 

i was thinking that thats why i asked see if anyone had fitted one and noticed a difference in power ?

Share this post


Link to post
Share on other sites
All depends on what is being done with the car and how much power is being chased. front mounts do increase lag and in most cases by a fair bit.

 

i hope not its already at 3900 for full boost :P

with the vf series sti turbo then a front mount will be better!!!

 

mainly looking to smooth out the power delivery and get it spool a bit faster mum dont want a huge cooler in the front just one that fills the air dam in the front bar without removing reo etc,

 

looking at a GT serires hybrid cooler as they offer the lest amount of pressure drop, they claim to speed up the spool up and increase power anyone know for sure before we run out and by it?

Share this post


Link to post
Share on other sites
All depends on what is being done with the car and how much power is being chased. front mounts do increase lag and in most cases by a fair bit.

 

X2...........

 

top mount have more response then front mount. i know this cuz i swapped mine bak to top mount.

 

only need front mount if u making more than 250kw i was told by trp

Share this post


Link to post
Share on other sites

the sti turbo obviosuyl came from an sti running a topmount... topmount is fine for up to 250atw like someone said. if youre worried about heatsoak, fit up a waterspray kit. if you want a bigger cooler, processwest or hyperflow do a good BIG top mount.

 

i fitted a hybrid to my my00 whilst still on the td04, and honestly i didnt notice any increase in lag, just got some hektik dose out of it

 

rexnet is good for wrx advice.

Share this post


Link to post
Share on other sites
the sti turbo obviosuyl came from an sti running a topmount... topmount is fine for up to 250atw like someone said. if youre worried about heatsoak, fit up a waterspray kit. if you want a bigger cooler, processwest or hyperflow do a good BIG top mount.

 

i fitted a hybrid to my my00 whilst still on the td04, and honestly i didnt notice any increase in lag, just got some hektik dose out of it

 

rexnet is good for wrx advice.

 

as far i know the turbo is the STi but its a hybrid with the largest rear housing not sure think its called a P20 or something it is running the standard top mount but as summer is coming up, my mum lives in gunnedah which is a contry town and air temps can rise up to and over 45 degrees and temps of road etc can go over 55-60 mark ... its fukin hot B)

 

the car dosent perform as well and i was worried about heat soak as if the cars left in sun i reckon that it would have heat soat before you even started the car. :lol:

 

so after fitting yours it didnt increase the spool up and lag of the car?

 

we have just bought new silicone intake pipe and APS cold air intake these are supposed to help with spool but wont know untill they are fitted i guess.

Share this post


Link to post
Share on other sites

yeah to be honest, i didnt notice any lag increase, but the td04 isnt laggy anyway, very small turbo. with the vf23 + larger rear + fmic, you might have a laggy wrx...

 

like i said, water spray kit ftw

Share this post


Link to post
Share on other sites
yeah to be honest, i didnt notice any lag increase, but the td04 isnt laggy anyway, very small turbo. with the vf23 + larger rear + fmic, you might have a laggy wrx...

 

like i said, water spray kit ftw

 

Thanks dude.

 

Has anyone had the tuned length extractors fitted? and or a turbo up pipe and noticed a difference?

Share this post


Link to post
Share on other sites

depends what figures and mods you're chasing..

 

as someone had said earlier.. up to 250kw u can still use the topmount without too much worry.. but bigger numbers will require a front mount..

Share this post


Link to post
Share on other sites

tuned length extractors are similar to the fmic - not needed, or wont be worth it, until youre up around 250kw atw. all youll doo is sacrifice low torque for a bit of high end power, and lose the trademark exhaust sound. massif not worth it

Share this post


Link to post
Share on other sites
tuned length extractors are similar to the fmic - not needed, or wont be worth it, until youre up around 250kw atw. all youll doo is sacrifice low torque for a bit of high end power, and lose the trademark exhaust sound. massif not worth it

 

no worries i have them here to be fitted but i dont think mum wants to lose the trademark sound :P so mabe just fit a turbo up pipe off the standard headers.

 

Thinkin about doing the fuel system first dose anyone know when the standard injectors / fuel pump on the GC8 run out of puff.

 

and dose the 040 pump bolt in?

 

Cheers

Share this post


Link to post
Share on other sites

dont think the 040 bolts in, ppl usually use a walbro in the wrxs. inj and fuel pump should be good up to about 180-atw. the inj are 440s in an my00, but in earlier models theyre just 380 so theyd need to upgraded earlier

Share this post


Link to post
Share on other sites

from talking to the JUN guys on behalf of a customer who is currently building a sti they recomend and upgraded top mount cooler for a street car / daily that has minimal modifacations as it provides sufficent cooling with minimal preassure drop.

 

for and application where full throttle is goingto be used for and extended period .ie circut / drag racing or bighwp car they recomend going to front mount.

 

on another note... the same customer recently melted his 2.0 (we just slotted in a 2.5) as the last workshop had fitted a set of ss extractors to the car removing the heat sheilding..

 

if you have ever had a look underthe front of those motors the pipes run arount th oil filter and the sump.... so basicaly several hunred deg. air was heating the oil to about 150 deg....

 

so if you go after market pipes please heat wrap them :D

 

just somthing to think about

Share this post


Link to post
Share on other sites

just a useless question... for a My99 what version is that? I see a lot of stuff for GC8 Version I-IV then GC8 V-VI...

 

Also do you need to upgrade any drivetrain for the 2.5L?

Share this post


Link to post
Share on other sites

as everyone said front mount for big big big power...but lower power top mount much more responsive ....i had a front mount when i had my wrx with hks turbo bak and a vf30...a fair bit of lag...

Share this post


Link to post
Share on other sites
just a useless question... for a My99 what version is that? I see a lot of stuff for GC8 Version I-IV then GC8 V-VI...

 

Also do you need to upgrade any drivetrain for the 2.5L?

 

my99 is the aus spec denomination for a wrx, the ver V, IV, VIII etc is for the sti model in japan, and im pretty sure the 99 is the version 5 or V

Share this post


Link to post
Share on other sites
dont think the 040 bolts in, ppl usually use a walbro in the wrxs. inj and fuel pump should be good up to about 180-atw. the inj are 440s in an my00, but in earlier models theyre just 380 so theyd need to upgraded earlier

cheers, do you know the colour of the injectors as an easy way to see what they are?

 

from talking to the JUN guys on behalf of a customer who is currently building a sti they recomend and upgraded top mount cooler for a street car / daily that has minimal modifacations as it provides sufficent cooling with minimal preassure drop.

 

for and application where full throttle is goingto be used for and extended period .ie circut / drag racing or bighwp car they recomend going to front mount.

 

on another note... the same customer recently melted his 2.0 (we just slotted in a 2.5) as the last workshop had fitted a set of ss extractors to the car removing the heat sheilding..

 

if you have ever had a look underthe front of those motors the pipes run arount th oil filter and the sump.... so basicaly several hunred deg. air was heating the oil to about 150 deg....

 

so if you go after market pipes please heat wrap them :D

 

just somthing to think about

 

thanks for that, deffinatly a good point ;) if i fit he up pipe its defo getting wrapped first!

Share this post


Link to post
Share on other sites

If you are getting vf series turbo stick to the top mount and have a water spray setup to spray on low boost = no heat soak problem. Even better buy one of the process west top mounts. The VF series turboes do not make enough power to warrant a front mount. Especially as the throttle body is at the back on the engine on the EJ20 which for a front mount is probably one of the worst places to have it.

 

There are other restrictions to take care of to help spool. An uppipe is one.

Share this post


Link to post
Share on other sites

It has a VF23 turbo fitted already not using the SS extractors now, mum wants to keep the note, fitting a larger turbo up pipe.

 

we fitted a silicone induction kit and a silicone Y pipe, its running more boost now but still has the standard boost controller.

 

i changed the gearbox oil with redline shockproof and diff oil as well.

 

its running heaps nicer and smoother bit more power and induction note heaps better.

 

going to get it tuned after uppipe and see how the fuel pump and injectors are going see if it need bigger ones yet.

Share this post


Link to post
Share on other sites

front mount will get u a bigger cooler but more laggy.... However the Classic shape with a big front mount looks SOOOO tough and u can put a dose pipe in as well hahahaha....

Share this post


Link to post
Share on other sites

have a look at process west tmic. i myself will be going the fmic route. 600 for a brand new hybrid fmic including in guard cai vs 900 for a process west tmic?

 

that said the tmic is less conspicuous and probably less attention from the popo too.

Share this post


Link to post
Share on other sites

true... lol but mum is 48 so she dosent usually have much trouble :P

 

and yes a front mount looks so tough on a rex...

 

the Y pipe and intake kit as definatly made the car run and spool up better will be interesting to see how the power figure has changed on the dyno.

Share this post


Link to post
Share on other sites

theres close to two meters of extra piping if you go FMIC, compared to...20 cm of Y pipe...

Share this post


Link to post
Share on other sites

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

Sign in to follow this  

×