LetThereBeBoost

I have read everything I can on 50 trim vs 57 trim and various things on super 60's and (the very few discussions) evo3 big 16g. I have been into DSM's for about 4 years now, but have decided to go the honda route starting with a turbo civic. Been searching and reading for about 2 months now and have read everything I can on how to do the d series right, and quite a bit on building a B series.

A sohc d series after rods, pistons, notching of the block and girdle, fuel pump, 720cc (room to grow), tuning, wideband, 2.5 bar map, everything from turbo manifold to fmic, whatever you feel is right with the oil pump, clutch, lsd, and tie rods, brakes, and suspension, is ready to handle 300-350 horse reliably on stock sleeves via proper tuning and no getting friendly with the rev limiter.

My argument comes down to a 50 trim turbo with a .63/.63 will give a wider power band that will level out up top but not drop off up to the sohc stock 7200 rpm limit. Where as a 57 trim with .48/.63 will spool a little later but pull like a raped ape from 5k-7200. At that point the valve train would have attention paid to it, to open up the power band to 8500.(possibly go for a mini-me swap at that point) or shift perfectly.

Then there is the evo3 16g. The turbo is capable of handling 350-380hp, yet from what I read, it falls off at top. This doesn't make sense when an evo3 pulls hard all the way to 1st gen DSM's 7400 limit. When not to mention Honda motors are known for being rev happy since thats where their power is at.

Thanks to those who can help clear this up. I'm hoping this turns into a good discussion as to help other new people to hondas.

quicksilver1689

whatever u do dont go with a 16g, and make sure you go with the .63 a/r housing. 50 trim would be fine for ur application, althought 57 would make 350-380 "easier"

LetThereBeBoost

If i was going to go big, id go 57 .48/.63 and focus on my valve train so I can widen the powerband. what im trying to do is utilize the mid rpms as well. I really dont feel like having to buzz my motor to 9k all the time. Maybe if I had two turbos, like 57 and 50 (.63/.63), I could run the 50 trim daily and when that person starts running their mouth i can swap turbo's and switch tunes. I am more so curious to see how a 95 hatch 5speed d16 with an evo3 and slicks will do against my friends 1st gen auto awd thats aiming for an evo3 as well. Maybe I am having a hard time with grasping the concept that these cars can't make decent power at 3500 no matter what way you look at it. I've been into dsm's for an extensive amount of time and just the basics of the ls1, so I can see its possible that I'm stuck on 4g63 concepts.

Tippyman

I'm going to run a 50 trim t3/t4 .42/.48. It will handle 300 hp without being laggy.

Newt Dog

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">I'm going to run a 50 trim t3/t4 .42/.48. It will handle 300 hp without being laggy.</TD></TR></TABLE>



The 50 trim is very responsive and comes in very early! The perfect turbo for the 300hp sohc street car!

zex_cool

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tippyman &raquo;</TD></TR><TR><TD CLASS="quote">I'm going to run a 50 trim t3/t4 .42/.48. It will handle 300 hp without being laggy.</TD></TR></TABLE>

huh ? what ?? where ??

16g and the t3 super 60 are very comparable with 300whp being there limit.

50trim[.48/.50or.63/.50] vs. 57trim[.63/50] is up to you. i went with the 50trim[.63/.50] to utilize the shitty powerband of the d series. its probably only 500rpm difference between the two but to each his own i guess.

fyi 50 trim with the .48 a/r exhaust housing makes a little more then 300whp on build block and stock everything else. with the bigger .63a/r exhaust housing on the same motor it made ~380whp with everything else still being stock.

LetThereBeBoost

If its really only a 500 rpm difference, thats nothing for me to worry about. Not to mention from what I hear a 57 trim really throws you back. $800 valve train and I have the power band I want. I was just not wanting to have to buzz the motor and make alot of noise to pull onto a street with cars coming.

If I went 50 trim I'd go with a .63 exhaust housing, thats without question. 380 is just about where I want to be so that works

If I plan on upgrading the valve train to buzz the motor, at what rpm will that 50 trim's power drop off? (heres where I think the 57 will take the cake.)

@ 380 hp (x amount of boost) what affect on quarter mile time is there between a .63/.63 50 trim and a .48/.63 57? i dont need exact numbers just ballpark.


Thanks for the help so far. I have searched and read just about everything I can find, but some of this is new to me.

SovXietday

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LetThereBeBoost &raquo;</TD></TR><TR><TD CLASS="quote">If i was going to go big, id go 57 .48/.63 and focus on my valve train so I can widen the powerband. </TD></TR></TABLE>

Ack, DSM logic is killin me.

The .63 on the 50trim will shine over the .48 on the 57trim as far as top end goes all day long. IMO, nothing smaller than a .63 should go on a Dseries.

Just get the .63 50trim. It will do what you want with a bit faster spool time. Not much though.

There really isn't that big of a difference between the 50 and the 57, I wouldn't expect mid boost AFRs to really change if you were to switch turbo's honestly. It will be on high boost where the 57 will inch out power wise over the 50.

LetThereBeBoost

if the 57 trim truly only takes 500-1000 more to fully spool i would definitely choose that turbo if it packs a lot more punch. dependent on how much power i can make on the vitara/eagle combo, i guess is what would be the deciding factor.

zex_cool

every little bit helps, even if it is only 500rpms. if you want top end power, you picked the wrong engine to do it with.

LetThereBeBoost

Nooo lol. i prefer to <U>not</U> have to take it over 5 grand if its just driving around. In this case the 50 trim is choice in my mind. if i like the power but not the lag i can always find a super 60. *shrug*

SovXietday

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by zex_cool &raquo;</TD></TR><TR><TD CLASS="quote">every little bit helps, even if it is only 500rpms. if you want top end power, you picked the wrong engine to do it with. </TD></TR></TABLE>

If you want to go there, don't even waste your time with a Honda. But that's not the point of this.

Like I said, 50trim will do what you want with a good powerband. No need to deliberate, the 57trim will spool not even 500rpms later but like I said, there isn't a big difference between them either. I don't know where you're getting the idea that you're going to put on a 57trim and BOOM big powa! Like I said, until you put race gas and try to max out that turbo you won't even see a very large difference.

LetThereBeBoost

Yea, thats become pretty clear and let me stress, I don't want a high reving motor, that was the big misconception that I had about these motors.

What would be a higher yet safe rev limit to set so that just in-case I miss 3rd I don't bounce off the limiter? (unless this isn't a problem after pistons and rods.)