Front mount better than top mount?

[Solja]

i went frontmount on my v3 engine bout a year ago, heres my opinion only. performance wise i didnt get that much more lag over over topmount , turbo kicked in 400rpm later with the piping like zarnahs pic. powerwise i did noticed a small gain but mainly no heatsoak like the topmount. I then flipped manifold and the turbo and theres little to no lag difference in when the turbo enguages than over the topmount. i do agree frontmounts are not needed on the adverage subie but i do reckon its worth it and im liking how simplifyed the engine can become once the topmount is removed and things start getting flipped

[pl0x]

 Solja said:

i went frontmount on my v3 engine bout a year ago, heres my opinion only. performance wise i didnt get that much more lag over over topmount , turbo kicked in 400rpm later with the piping like zarnahs pic. powerwise i did noticed a small gain but mainly no heatsoak like the topmount. I then flipped manifold and the turbo and theres little to no lag difference in when the turbo enguages than over the topmount. i do agree frontmounts are not needed on the adverage subie but i do reckon its worth it and im liking how simplifyed the engine can become once the topmount is removed and things start getting flipped

+1 much more space now, can run catch cans , oil cooler under the scoop etc

[cpt kernow]

Well here's a good one. I read Autospeed mag online and they do loads of funny tests on cars. One was with an air pressure meter which enabled them to see the difference in pressures around the engine bay and on the frontal body work.

They found in a v7 wrx that without the undertray fitted the top mount actually had air coming OUT of it up to speeds of 80k's. So that meant it was a pre-heater not an Intercooler. With the tray fitted the pressure on the bonnet was higher than the engine bay and the tmic worked properly.

inho Front mounts reek of boy-racer unless they are fitted to something really tidy and well done. Nothing makes me laugh more than a galant with no bumper flashing his aluminium to the world

[Guest]

Thanks for the great response. So basically a FMIC is good for a car that will be pushed to the limits whereas a the top mount is still a good choice for the street. ??? 8) ;D

 RITALN said:

i cant believe people are seriously debating this topic.

gotta be the most common, oldest suby question. just use google ffs.

Well I did actually google it, and couldnt find anything specific on Subarus. And I didnt want to assume that all cars react to a FMIC the same way. My last car was an FD and it is accepted amongst many members of the FD community that FMICs on an FD are a bad choice due to the heat that the rotary produces alongside the twin turbo setup which causing over heating engines. So most members will usually upgrade with either a good top mount or V style setup. From what I can gather, Subarus dont really suffer for heat that many TT setups usually create on other cars.

[Too Broke]

FMIC's aren't a necessary ingredient in a high powered car (I would consider 250 - 300kw @wheels high power). Although they may help a little.

The Speedsource WRX runs a Factory topmount and is pumping out over 300kw@wheels.

I did have one on my V4 Coupe, and I will be the first to admit, the main reason was the 'wank-value', but I'm sure it made it pull a little harder.

If I had to make the decision again though - I wouldn't bother.

[Scoobydoo]

I've often been told to put an FMIC on mine... mainly cos my bumper looks very empty!

But no, I'm running an ARC top mount and I find it pretty good. No lag that I've noticed and it's certainly larger than a stock one!

[Guest]

TMIC on a standard legacy should be fine.. couldn't see much benefit if you went FMIC on a stock Legacy...

But on that note, I was changing to a FMIC on my GTB once converted .. running larger fuel pump, reg, split mod, bigger injectors, slight worked engine (EJ20K not R) .. the FMIC design for the FMIC would be best with manifold flip.. that was to come later...

research coughed up, these ideas.

The idea was to get away from the full body extended pipe wrap like GF8 -GC8 which (with hope) will keep the lag minimal.. and produce direct air flow through.. similar idea to an exhaust straight pipe, I guess.

[Andrew NR]

Has anyone installed pre & post air temp sensors to find out which intercooler cools the air better....or just done it for fun or curiosity?

[Guest]

 Andrew NR said:

Has anyone installed pre & post air temp sensors to find out which intercooler cools the air better....or just done it for fun or curiosity?

Think some did do it.. I remember something from the last forum.. write up with pics.. showing more air flow through the front..

[Guest keltik]

Credit to optical for the original post. somebody should sticky this

[Joker]

was gunna take away cred for un-readability, but it is viewable if you save it and view OR "right-click" view image and zoom

forum is resizing by default to fit within limits

[Andrew NR]

So nothing beats a good FMIC setup but you can get performance gains out of a good TMIC. I like the look of the APS dual entry top mount: http://www.airpowersystems.com/wrx/intercooler.htm

[Guest]

Jaycar have great digital temp gauges - i use them all the time.

The Sti intercooler not tested works alot better than the WRX one tested. I have seen one test where a car was tuned with an Sti ver 7? intercooler did about 392hp. Then a FMIC was added it managed about 407hp. Dyno's of course favour FMIC due to the inability to simulate 100km/h windflow.

Remember at best your going to gain 1% of power for every 4 degrees C.

[Simon C]

Is a few kW of top end worth the turbo lag and worse throttle response though? I'd rather have my turbo spool up a few hundred RPM sooner and have more instantaneous response to the pedal, for real world driving.

[Too Broke]

 Simon C said:

Is a few kW of top end worth the turbo lag and worse throttle response though? I'd rather have my turbo spool up a few hundred RPM sooner and have more instantaneous response to the pedal, for real world driving.

Exactly!!

[Swindog]

 MAD said:

TMIC on a standard legacy should be fine.. couldn't see much benefit if you went FMIC on a stock Legacy...

But on that note, I was changing to a FMIC on my GTB once converted .. running larger fuel pump, reg, split mod, bigger injectors, slight worked engine (EJ20K not R) .. the FMIC design for the FMIC would be best with manifold flip.. that was to come later...

research coughed up, these ideas.

The idea was to get away from the full body extended pipe wrap like GF8 -GC8 which (with hope) will keep the lag minimal.. and produce direct air flow through.. similar idea to an exhaust straight pipe, I guess.

Thats AWESOME!

Thats my next mod after the twisted turbo then!

[THUNDA]

top mount ftw, the intake piping is soo short makes fuck all lag

fmic, yeah they are all good, but i rekon most of the time upgrading to a fmic is just for looks tbh, unless you're running high horse power then of course fmic would own up, (assuming the car is moving foward, but obviously no-one would give a rats ass about modding their car if it didnt actually move foward)

[BC5RA]

THUNDA, saw you driving down dominion road yesterday evening, recognized you from your clear indicator's.

Nice to see non kebab RS.

[THUNDA]

haha yeah i live just off dominion road near balmoral ways

non kebab rs? i suppose ill take that as a compliment lol 8)

[Guest boostcut]

 Swindog']

[quote name='MAD said:

TMIC on a standard legacy should be fine.. couldn't see much benefit if you went FMIC on a stock Legacy...

But on that note, I was changing to a FMIC on my GTB once converted .. running larger fuel pump, reg, split mod, bigger injectors, slight worked engine (EJ20K not R) .. the FMIC design for the FMIC would be best with manifold flip.. that was to come later...

research coughed up, these ideas.

URL=http://img210.imageshack.us/my.php?image=ttsticonversion005.jpg][/url]

The idea was to get away from the full body extended pipe wrap like GF8 -GC8 which (with hope) will keep the lag minimal.. and produce direct air flow through.. similar idea to an exhaust straight pipe, I guess.

Thats AWESOME!

Thats my next mod after the twisted turbo then!

the problem with this set up is that in nz the frontal impact rules are verry strict. i got told by a lvv certifyer that any car with a frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail. and i see this has the rad support modifyed. however all good for track work

[Guest]

 boostcut']

[quote name='MAD said:

TMIC on a standard legacy should be fine.. couldn't see much benefit if you went FMIC on a stock Legacy...

But on that note, I was changing to a FMIC on my GTB once converted .. running larger fuel pump, reg, split mod, bigger injectors, slight worked engine (EJ20K not R) .. the FMIC design for the FMIC would be best with manifold flip.. that was to come later...

research coughed up, these ideas.

URL=http://img210.imageshack.us/my.php?image=ttsticonversion005.jpg][/url]

The idea was to get away from the full body extended pipe wrap like GF8 -GC8 which (with hope) will keep the lag minimal.. and produce direct air flow through.. similar idea to an exhaust straight pipe, I guess.

Thats AWESOME!

Thats my next mod after the twisted turbo then!

the problem with this set up is that in nz the frontal impact rules are verry strict. i got told by a lvv certifyer that any car with a frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail. and i see this has the rad support modifyed. however all good for track work

Depends on which LVV certifiers I guess, I past this idea through a couple certifiers in west Auckland all seem to be good.. yet I do however understand what you mean, depending on who you see I reckon as to what they would be called a modified rad rail.. even the bumper rail will need holes drilled into it to fit a GF8 - GC8 FMIC to a legacy (standard) would that be classed at a modification to the bumper rail?

To be technical and a pain in the A** one could just weld the brackets in place to the RAD rail... ie: frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail no metal taken out, no fail... in theory only (LOL) dumba** for sure but possible just to work around the laws..

Better idea would be just to build the brackets off the bumper rail.. if a standard setup passes LVV unsure how this idea would be failed..

(image is of the idea only) no bumper rail was hurt during the PS modification. (NZ MOD LAW S$#K)

[Guest boostcut]

 MAD']

[quote name='MAD said:

TMIC on a standard legacy should be fine.. couldn't see much benefit if you went FMIC on a stock Legacy...

But on that note, I was changing to a FMIC on my GTB once converted .. running larger fuel pump, reg, split mod, bigger injectors, slight worked engine (EJ20K not R) .. the FMIC design for the FMIC would be best with manifold flip.. that was to come later...

research coughed up, these

The idea was to get away from the full body extended pipe wrap like GF8 -GC8 which (with hope) will keep the lag minimal.. and produce direct air flow through.. similar idea to an exhaust straight pipe, I guess.

/quote]

Thats AWESOME!

Thats my next mod after the twisted turbo then!

the problem with this set up is that in nz the frontal impact rules are verry strict. i got told by a lvv certifyer that any car with a frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail. and i see this has the rad support modifyed. however all good for track work

Depends on which LVV certifiers I guess, I past this idea through a couple certifiers in west Auckland all seem to be good.. yet I do however understand what you mean, depending on who you see I reckon as to what they would be called a modified rad rail.. even the bumper rail will need holes drilled into it to fit a GF8 - GC8 FMIC to a legacy (standard) would that be classed at a modification to the bumper rail?

To be technical and a pain in the A** one could just weld the brackets in place to the RAD rail... ie: frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail no metal taken out, no fail... in theory only (LOL) dumba** for sure but possible just to work around the laws..

Better idea would be just to build the brackets off the bumper rail.. if a standard setup passes LVV unsure how this idea would be failed..

(image is of the idea only) no bumper rail was hurt during the PS modification. (NZ MOD LAW S$#K)

i was meaning more where the piping goes through the headlight hole.... its been modifyed in there. but yeah diffrent cert dudes diff rules i guess

[Guest]

 boostcut']

[quote name='MAD said:

TMIC on a standard legacy should be fine.. couldn't see much benefit if you went FMIC on a stock Legacy...

But on that note, I was changing to a FMIC on my GTB once converted .. running larger fuel pump, reg, split mod, bigger injectors, slight worked engine (EJ20K not R) .. the FMIC design for the FMIC would be best with manifold flip.. that was to come later...

research coughed up, these

The idea was to get away from the full body extended pipe wrap like GF8 -GC8 which (with hope) will keep the lag minimal.. and produce direct air flow through.. similar idea to an exhaust straight pipe, I guess.

/quote]

Thats AWESOME!

Thats my next mod after the twisted turbo then!

the problem with this set up is that in nz the frontal impact rules are verry strict. i got told by a lvv certifyer that any car with a frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail. and i see this has the rad support modifyed. however all good for track work

Depends on which LVV certifiers I guess, I past this idea through a couple certifiers in west Auckland all seem to be good.. yet I do however understand what you mean, depending on who you see I reckon as to what they would be called a modified rad rail.. even the bumper rail will need holes drilled into it to fit a GF8 - GC8 FMIC to a legacy (standard) would that be classed at a modification to the bumper rail?

To be technical and a pain in the A** one could just weld the brackets in place to the RAD rail... ie: frontmount that has been fitted and steel has been taken out ie: the bumper support or radiator support panels would fail no metal taken out, no fail... in theory only (LOL) dumba** for sure but possible just to work around the laws..

Better idea would be just to build the brackets off the bumper rail.. if a standard setup passes LVV unsure how this idea would be failed..

(image is of the idea only) no bumper rail was hurt during the PS modification. (NZ MOD LAW S$#K)

i was meaning more where the piping goes through the headlight hole.... its been modifyed in there. but yeah diffrent cert dudes diff rules i guess

I know what you mean, sorry if i miss-understood before.. another mate thought that it cut as well.. but apparently they were just thinner pipes, you can just see a size reduction on the pipe in the picture there (or not).. which is why the bumper rail was removed to get it to fit better.(in the first picture).. I'll try and find the article about it.. it was a good read.

My thoughts on it was to just make the silicone elbows longer at one end, maybe longer and reduce the size of the silicone hose at one end, that goes under the head lights, then pipe the rest..

There must be a way around it.. if one just thinks outside the box.. (my 2 cents)

sorry my misstake B 4

[Guest]

i believe standard is always better ...as for myself i have a front mount which yes is aftermarket by previous owners bt i just like the look of it i notice the lag alot and as my car is rwd i notice quite alot bt i guess its personal prefrence if cars went made to have different mounts then no one whould make parts to change them

[BC5RA]

 msevhoe said:

i believe standard is always better ...as for myself i have a front mount which yes is aftermarket by previous owners bt i just like the look of it i notice the lag alot and as my car is rwd i notice quite alot bt i guess its personal prefrence if cars went made to have different mounts then no one whould make parts to change them

This is a very old and frankly redundant thread, have you driven many (if any) OE cooler WRX's or FMIC? there's many factor's that contribute to Lag.