Estimated HP gains - bolt on mods and reflash?

[old greg]

Originally Posted by Caliban

if turbo can't be fitted under factory bonnet..how did they put a turbocharged motor under the BRZ GT300? the bonnet of BRZ GT300 doesn't look much different than the production model.

The bonnet may be about the same, but nothing else is. JGTC cars are so far from production models that it's not even funny. They have almost nothing in common, or less. My guess is that both the engine and the driver are several inches further back than they would be in a production BRZ, and that's where the extra room is coming from.

Originally Posted by Masuda-san

We can fit tougher valve springs, and that would allow the BRZ to rev much higher, maybe to 9000 rpm.

I like the sound of that. He seems to be saying that the only thing keeping the revs down is valve float (ie. the stock bottom end is already good enough). So I/H/E + cams, valve springs and a reflash could potentially be good for 250+ hp.

[balance]

Originally Posted by old greg

I like the sound of that. He seems to be saying that the only thing keeping the revs down is valve float (ie. the stock bottom end is already good enough). So I/H/E + cams, valve springs and a reflash could potentially be good for 250+ hp.

I am also down for 20~30% increase in power only if it is safe from the reliablity standpoint and the cost of the necessary modifications is reasonable.

How much do you think 'I/H/E + Cams + Valve Springs + Ecu reflash' would cost?

I'm thinking 'easy $3K' when going with quality parts....
NA power upgrades are costly....

[Levi]

Sorry, but 3K is worthy. When you make turbo upgrades you also have to upgrade oil-cooler, intercooler and other parts also.

[old greg]

Originally Posted by balance

How much do you think 'I/H/E + Cams + Valve Springs + Ecu reflash' would cost?

I'm thinking 'easy $3K' when going with quality parts....
NA power upgrades are costly....

Depends on how you define "quality"

But yeah $3k ought to cover it. And honestly that's an absolute bargain for 50 hp out of an N/A 2L. You'd spend $4-5K minimum on a turbo kit not counting installation and tuning which might only be good for ~300 hp or so on stock internals (total guess). So price to performance wise it would actually be a very good value at that power level.

[Homemade WRX]

Originally Posted by balance

How much do you think 'I/H/E + Cams + Valve Springs + Ecu reflash' would cost?

I'm thinking 'easy $3K' when going with quality parts....

yeah, easy $3k.

You roughly figure that for quality parts:
intake = $250 for a basic one or upwards of $700 like some of the nice S2k ones.
exhaust = $1000
exhaust manifold/header = $700
cams (subaru) = $800-1000....BC's for like $550
some decent ovate beehive springs = $400
then get a tune...$x

so without a tune firgured in, you're roughly $2900 (low end) up to about $3800 (high end). Then factor in that in order to do valve springs, the head will probably have to come off too. Not sure if we'll be able to pressurize the camber and pull springs on this head. So then factor in some head gaskets and more time.
May as well do valves, a nice valve job and some port work while you're in there


...yes I know the cat is on the exhaust manifold on the FA20.

[catharsis]

Originally Posted by Homemade WRX

yeah, easy $3k.

You roughly figure that for quality parts:
intake = $250 for a basic one or upwards of $700 like some of the nice S2k ones.
exhaust = $1000
exhaust manifold/header = $700
cams (subaru) = $800-1000....BC's for like $550
some decent ovate beehive springs = $400
then get a tune...$x

so without a tune firgured in, you're roughly $2900 (low end) up to about $3800 (high end). Then factor in that in order to do valve springs, the head will probably have to come off too. Not sure if we'll be able to pressurize the camber and pull springs on this head. So then factor in some head gaskets and more time.
May as well do valves, a nice valve job and some port work while you're in there


...yes I know the cat is on the exhaust manifold on the FA20.

If you're spending 1k on an exhaust but only 700 on a header, you're doing it wrong.

[Homemade WRX]

Oh, I just grabbed a few random prices with a quick search.

I do agree that an exhaust manifold is way more crucial than exhaust.

oh and that manifold was some mass produced piece.

[catharsis]

Originally Posted by Homemade WRX

Oh, I just grabbed a few random prices with a quick search.

I do agree that an exhaust manifold is way more crucial than exhaust.

oh and that manifold was some mass produced piece.

Ah ok gotcha :happy0180:.

[NA_T]

If only tougher valves springs would do the trick to make the engine rev to 9.000rpm, I dont understand why Toyota/Subaru wouldn't have done it themselves in the first place? This sounds too good to be true, but if it is.. awesome.

[WingsofWar]

Im sure both companies' engineers and project planners have thought of plenty power adders or parts that could further increase the cars performance. But were omitted from the final plans to keep costs down.

[Homemade WRX]

Originally Posted by NA_T

If only tougher valves springs would do the trick to make the engine rev to 9.000rpm, I dont understand why Toyota/Subaru wouldn't have done it themselves in the first place? This sounds too good to be true, but if it is.. awesome.

I'd say emissions. The larger the rev range, the harder the FTP cycle (RMC's for that matter too) and the larger your NTE window. To make the 9k worthwhile, you have to make trade offs down low.

[serialk11r]

I think this engine would have one of the longest strokes and THE poorest rod:stroke ratio of any engine that revs past 8k if they did that, which makes me skeptical (even if they could get emissions to be acceptable at >8000 rpm).

[Homemade WRX]

Originally Posted by serialk11r

I think this engine would have one of the longest strokes and THE poorest rod:stroke ratio of any engine that revs past 8k if they did that, which makes me skeptical (even if they could get emissions to be acceptable at >8000 rpm).

you do know that the K20 is an 86mm stroke and 86mm bore as well, right?

I have a few things up my sleeve for the FA engine based off of what I already know for the FB25 and handed down from extensive EJ building and K-series work.


put simply, I'm not scared

[tranzformer]

Originally Posted by Homemade WRX

I have a few things up my sleeve for the FA engine based off of what I already know for the FB25 and handed down from extensive EJ building and K-series work.

What are you currently thinking?