[Stunnerman]

Hey all,

I want 400whp reliably!!! on pump (93oct) for my srt4.
Mod List:
AGP UHP
HKS BOV
BFMIC
Stage 2 clutch
Mopar CAI
Oil Catch
Catless DP -> full 3' exhaust
KW V2 Coilovers
Agp Wastegate
Walbro 255 hpfp

Debating on:
Stage 2/3 injectors
or
750cc deatschwerks

MY questions are:

Is there a noticeable difference between .48 and .63 on either of these turbos?
Is it worth it to water cool these turbos since I'll be running hot on pump gas?
Would both of these turbos easily reach 400whp reliably?
Which of the 2 injectors would you recommend?

I'm going for street fun, no plans on tracking. Just want some added pep. I'm already dusting Sti's with stock turbo.

 

[JmalB]

No practical experience, myself. But per AGPs website, .48 will spool up sooner and the .63 will make more power at the top end.
Go water cooled if you can. Reduces idle time after getting on it.
Both turbos will give you 400whp (per AGP's page)
I would recommend 1000cc injectors.

And now I've spent far too much time on AGPs page building my own kit. Which I won't order... yet.

 

[AlmightyFork]

I'm another who hasn't done it, but from reading these forums I've found that most pump gas 50 trims end up between 360-380 on a conservative pump gas tune. You might consider meth/e85 to get the extra octane needed to safely push your tune to 400+.

 

[Simon.Starkie]

I'm another who hasn't done it, but from reading these forums I've found that most pump gas 50 trims end up between 360-380 on a conservative pump gas tune. You might consider meth/e85 to get the extra octane needed to safely push your tune to 400+.

...careful, water or meth injection systems may not have any fail-safe so if the meth injection fails for any reason, your motor is exposed.

I prefer the water cooled journal bearing small turbo like Stage 3 for fun street driving with as little lag as possible...ball bearing turbos can have their own problems...


Not sure about the .48 vs .63 aspect ratio but I'd at least ask the vendor for a turbo map...for both...

A dual scrolling turbo might be the best of both worlds..spool vs lag

 

[AlmightyFork]

...careful, water or meth injection systems may not have any fail-safe so if the meth injection fails for any reason, your motor is exposed.

True. Only mentioned it so loosely because it was in the original post. E85 or meth will make 400 on pump gas easier to attain nonetheless.

 

[Simon.Starkie]

True. Only mentioned it so loosely because it was in the original post. E85 or meth will make 400 on pump gas easier to attain nonetheless.

Yes, it's not a good idea to tune these cars on the ragged edge with no safetynet....
Unless of course one is an out an out racer and doesn't mind rebuilding their motor over and over and...

 

[AlmightyFork]

AEM's kit has a failsafe.

 

[Simon.Starkie]

AEM's kit has a failsafe.

That's very cool. There wasn't anything like that available when I was doing this. Still need a full compliment of EGT and A/F monitoring gear as well as a proper tune and device for flashing it...all this in addition to a decent exhaust and down pipe, intake, FMIC, head work, forged Pistons, wheels, tyres, big brakes, coil overs and probably more. It is not just the turbo and it's claimed HP that matters.

 

[Stunnerman]

Yes, it's not a good idea to tune these cars on the ragged edge with no safetynet....
Unless of course one is an out an out racer and doesn't mind rebuilding their motor over and over and...

You saying 400whp is asking for a blown motor? I thought these engines were good upto 500-550?

I'm another who hasn't done it, but from reading these forums I've found that most pump gas 50 trims end up between 360-380 on a conservative pump gas tune. You might consider meth/e85 to get the extra octane needed to safely push your tune to 400+.

Ah I hear you. I purchased the s252sxe kit last night from Cindy at fwd performance. She gave me a lot information and recommended me it. Love a quick spoolin smile maker

 

[Simon.Starkie]

Only takes one bad detonation to hurt a motor regardless of what anyone thinks is the safe limit for HP and TQ...

 

[Stunnerman]

Only takes one bad detonation to hurt a motor regardless of what anyone thinks is the safe limit for HP and TQ...

Very true. I've heard and read lots of stories of people having ~400whp for years with no issues. Just keep up with regular maintenance. But ofcourse, there's always the one unlucky guy. Just pray it's not me. Sunk 13k in this bad boy during the winter in prep for spring.

 

[tbagg1ns]

Very true. I've heard and read lots of stories of people having ~400whp for years with no issues. Just keep up with regular maintenance. But ofcourse, there's always the one unlucky guy. Just pray it's not me. Sunk 13k in this bad boy during the winter in prep for spring.

Damn dude it's taken me all 7 years of ownership to spend that much, if at all😂 Can't wait to see it when it's done!