turboLSef

I'm currently gathering parts for my build... I'm building a D16A6 Bottom end with a D16Z6 head for turbo. Ive already got Vitara pistons and Eagle H-beams for the bottom end.. Now I'm looking into getting Supertech valvetrain (black Valve's, dual springs, and titanium retainers)

My question is should I get .5mm or 1mm oversized on the valve's? Is there any reason I should stay stock size?? what are the pros and cons to the oversized valves for boost? Any help/advice/opinion will be much appreciated TIA

Nic

oscarmayer

.5mm the 1.-mm could touch if something gets slightly out of wack or they get reved too high and expand a little. the .5mm are about the best you shoudl go with the D unles you have lots of $ to completely redo the valving.

turboLSef

thanks for the response... bump for more advice

turboLSef

any more advice??

RyanEJ8

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by oscarmayer &raquo;</TD></TR><TR><TD CLASS="quote">.5mm the 1.-mm could touch if something gets slightly out of wack or they get reved too high and expand a little. the .5mm are about the best you shoudl go with the D unles you have lots of $ to completely redo the valving.</TD></TR></TABLE>

Gitwidit may have had this problem. I need to give him a call for an update.

ELSpool

I run .5mm bigger because thats the only size availabe for the D16 through Supertech. I know turbodcx ran 1mm bigger, lots of boost, and 500+whp without problems. I figured teh D16 head needs as much help as possible to flow more. We are already down on displacement and a cam over the rest

turboLSef

TTT for more input

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RyanCivic2000 &raquo;</TD></TR><TR><TD CLASS="quote">Gitwidit may have had this problem. I need to give him a call for an update.</TD></TR></TABLE>

cool... let me know. its much appreciated!!

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">I run .5mm bigger because thats the only size availabe for the D16 through Supertech. I know turbodcx ran 1mm bigger, lots of boost, and 500+whp without problems. I figured teh D16 head needs as much help as possible to flow more. We are already down on displacement and a cam over the rest </TD></TR></TABLE>

I was told SuperTech does make 1mm over for the D16... but I was originally interested in the 1mm over because of TurbodCX's 500+ setup how do you like your Supertech stuff??

ELSpool

It has worked out well. But the spec sheet that came with it was so far off. Spring height was much shorter than stated. I used to run the Zex stage 2 cam, but had to go back to stock as my coil bind with the big lift from that cam wasn't worth the risk of a motor. So i was pretty pissed when my head guy called stating your cutting it too close with that cam, and also concidering I ran it all last year on a stock valve train...

turboLSef

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">It has worked out well. But the spec sheet that came with it was so far off. Spring height was much shorter than stated. I used to run the Zex stage 2 cam, but had to go back to stock as my coil bind with the big lift from that cam wasn't worth the risk of a motor. So i was pretty pissed when my head guy called stating your cutting it too close with that cam, and also concidering I ran it all last year on a stock valve train...</TD></TR></TABLE>

So, Supertech's spec sheet's info is off?! well that sucks... Im also looking at a zex cam.. not too sure what Im looking for. but maybe I should look into a different cam or even different valvetrain?! what would be a good alternative to zex for a cam then?

ELSpool

concidering the power I made, and peaking at 7800rpm with the stock cam, IMO, don't waste your money on a cam. Spend it on a professional port job, a good valve job to follow up. The sohc head is by far the best place to see significant gains from working it over.

beerbongskickass

If your going through all that work building the head and bottom end why don't you get some good forged pistons? Might as well do it right the first time...

turboLSef

I was checking out your setup.. those are some nice #'s I wasn't gonna buy the cam for a bit. Im going to use my stock cam in the mean time... so I will stick with the SuperTech valvetrain at .5mm over.........

Should I go with the dished valves or flat? My compression should be around 8.7:1 with a stock head.. what effects will either style valves have on my comp. ratio?! thanks

RyanEJ8

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">concidering the power I made, and peaking at 7800rpm with the stock cam, IMO, don't waste your money on a cam. Spend it on a professional port job, a good valve job to follow up. The sohc head is by far the best place to see significant gains from working it over.</TD></TR></TABLE>

I'm starting to wish I had done this.

turboLSef

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beerbongskickass &raquo;</TD></TR><TR><TD CLASS="quote">If your going through all that work building the head and bottom end why don't you get some good forged pistons? Might as well do it right the first time...</TD></TR></TABLE>

I want to give the Vitara pistons a try.. they were a great price and also the cast grade is supposed to be a good alternative to forged... I think if it is tuned well they shouldn't be a problem...

Now Im just wonder about how much I should expect to pay from a good machine/head shop for PnP, valve job and assembly?..
bump for more info

beerbongskickass

I understand they are a good price, but it looks like your spending a lot on the head and other things. When you end up wanting a little more power the only thing holding you back would be the pistons, there not that great. Your stock honda pistons with that low of a compression would probably work just as well with a good tune. I just always like to plan for upgrade because cars are expensive and it will save money in the long run.

EnzoSpeed

I always say get good pistons and rods from the start. That way, you can make whatever power you want down the road. But if you put in crappy pistons or rods, then want more power, it's a big, expensive pain in the *** to re-do your shortblock again.

RyanEJ8

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboLSef &raquo;</TD></TR><TR><TD CLASS="quote">

I want to give the Vitara pistons a try.. they were a great price and also the cast grade is supposed to be a good alternative to forged... I think if it is tuned well they shouldn't be a problem...

Now Im just wonder about how much I should expect to pay from a good machine/head shop for PnP, valve job and assembly?..
bump for more info </TD></TR></TABLE>

Cast is never a good alternative to forged. The only reason the Vitara pistons take a little more boost than the stock Hondas is the low compression.

turboLSef

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RyanCivic2000 &raquo;</TD></TR><TR><TD CLASS="quote">

Cast is never a good alternative to forged. The only reason the Vitara pistons take a little more boost than the stock Hondas is the low compression.</TD></TR></TABLE>

The <U>cast grade</U> of the Vitara's is a good alternative to forged.. for more info on that: https://honda-tech.com/zerothread?id=954478
I know that forged would be best.. but I dont mind trying cast for the price difference. I have a few friends boosting 20+ psi daily on <U>stock</U> bottom ends with a good tune and have been that way for a while now..

but... back to the head. any other advice? should I go with the flat or dishes valves??

ELSpool

I think flat were made for all motor guys looking for higher compression, dished for the turbo guys trying to keep lower compression.

turboLSef

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">I think flat were made for all motor guys looking for higher compression, dished for the turbo guys trying to keep lower compression.</TD></TR></TABLE>

Im wondering what my compression is going to be with either style valve... Its already I think around 8.7:1..... any ideas?!

beerbongskickass

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turboLSef &raquo;</TD></TR><TR><TD CLASS="quote">

The <U>cast grade</U> of the Vitara's is a good alternative to forged.. for more info on that: https://honda-tech.com/zerothread?id=954478
I know that forged would be best.. but I dont mind trying cast for the price difference. I have a few friends boosting 20+ psi daily on <U>stock</U> bottom ends with a good tune and have been that way for a while now..
</TD></TR></TABLE>

20+ psi doesn't mean ****. Let's see those pistons handle 500+ whp like a good set of forged pistons would. It aint going to happen.

A good set of forged pistons are like 400-500 bucks, so they aren't that much more. They are a lot more important than building the head. I would much rather have a solid bottom end with a stock head than have a $1500 head and not so great bottom end.

SOHC_MShue

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">concidering the power I made, and peaking at 7800rpm with the stock cam, IMO, don't waste your money on a cam. Spend it on a professional port job, a good valve job to follow up. The sohc head is by far the best place to see significant gains from working it over.</TD></TR></TABLE>
I have swapped between the stock and zex 59300 cam in my turbo sohc and i can tell you the zex cam made a world of a difference. My car has so much more top end with it.

turboLSef

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beerbongskickass &raquo;</TD></TR><TR><TD CLASS="quote">

20+ psi doesn't mean ****. Let's see those pistons handle 500+ whp like a good set of forged pistons would. It aint going to happen.

A good set of forged pistons are like 400-500 bucks, so they aren't that much more. They are a lot more important than building the head. I would much rather have a solid bottom end with a stock head than have a $1500 head and not so great bottom end.</TD></TR></TABLE>

thanks for your input bro

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">
I have swapped between the stock and zex 59300 cam in my turbo sohc and i can tell you the zex cam made a world of a difference. My car has so much more top end with it. </TD></TR></TABLE>

good to know.. thats the cam Ive been looking at. What valvetrain are you using with it?

ELSpool

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">
I have swapped between the stock and zex 59300 cam in my turbo sohc and i can tell you the zex cam made a world of a difference. My car has so much more top end with it. </TD></TR></TABLE>

Show me dyno plots.

turboLSef

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ELSpool &raquo;</TD></TR><TR><TD CLASS="quote">

Show me dyno plots.</TD></TR></TABLE>

are there? Id like to see the gains too