Sr20det +1mm valves help???

[stevecorrado88]

Was looking into it and does anyone have hands on experience with them?? I'm right around 380 hp and I'm gonna build a head just wondering what exactly needs to be done for the install and a ball park figure on the price a machine shop might charge?

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what are your end goals? take this into acount if not you will just ne wasting $

[stevecorrado88]

Well here's my setup:
3071r .63 ar 21psi on external wastegate
Top mount setup
Power fc djetro
Tomei poncams
Isis intake mani
Q45 tb
740cc injectors
I believe that's it my goal is to get around 400-450 and use my setup to its potential. I'm building a head now because I keep floating shims and rockers.

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No need for valves at that level
We have made 400-450 on unopened stock SR's with gt30's

[stevecorrado88]

I understand that but there is also no need for this much hp lol I get what your saying I also could just run more boost maybe get bigger cams blah blah blah if I do the valves I can gain more hp with my setup and even more hp with more boost, it should make my power band even stronger. I was also thinking about a bigger turbo housing in the future. I guess I'm not asking why not to get it just what would need to be done if I did get them.

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It's all about choosing the right parts an working together.
Look at my sig. That's on a stock head with only cams , springs and rocker stoppers an intake sprocket all else is stock
Stock valves stock valve seals stock retainers stock ports

[stevecorrado88]

Ok I'm just wondering the price range and stuff how much is a waste of money?ive wasted a lot of money building a 240 with an sr lol what's a few bucks more.

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Take into account valves, machine work
All that adds up.
Unless u plan to push it hard hard keep it simple

[stevecorrado88]

Any experience out there????

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you say you have floating shims and rockers
what are you reving it

[stevecorrado88]

Rev limit is at 7300

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Rev limit is at 7300

at that rev limit you are fine with just springs.
your going to spend about $500-700 on valves/springs/retainers
plus machine work all in all you will spend $1500ish just on parts an machine work without porting

i rev to 8100 without issues with just springs

[MadScientist]

If your going to do +1 overs you might as well rebuild the entire head... its what I did. Basically, if you upgrade just valves now, then guides later, then springs and seats, then solids, etc... its just more work... kill it all in one sweep.

I think I have about $1200 in machine work on my head with PnP, Guides, Valves, Solids, etc.. not including parts...

Highly suggest SuperTech!!

[stevecorrado88]

Plan was just valves,springs, retainers I haven't researched much on solid lifters and I might do double guides instead of the shim.

[jr_ss]

Steve, go with bigger cams before you do any head work other than springs. I really think your small cams is what is killing your power potential. There is absolutely no reason to go +sizes in valves unless your building a dedicated car or have maxed the flow potential of the head. You have not reached that level and I personally think you're pissing into the wind with going to a bigger valve.

[stevecorrado88]

I like tomei procams 260/260 which is 12.00 lift not sure if I like 270/270 that seems over kill. I'm planning on getting rid of rev limit and rev to 8500 sometimes 9 cuz it seems like my problems happen cuz I love rev limit.

[jr_ss]

I like tomei procams 260/260 which is 12.00 lift not sure if I like 270/270 that seems over kill. I'm planning on getting rid of rev limit and rev to 8500 sometimes 9 cuz it seems like my problems happen cuz I love rev limit.

You may reach 8k if you're lucky, you won't see 9K with that turbo or a stock head.

[stevecorrado88]

Why won't I reach that and this whole thread is about me building a head

[jr_ss]

Why won't I reach that and this whole thread is about me building a head

Because you're running a turbo capable of 500ish hp. Santos revs to 8100 with a turbo quite a bit larger. You just don't have enough CFMs in the 3071R to pull off 8500 or higher. If the DET head was more efficient, maybe, but it doesn't flow all that well compared to other 4cyl heads.

Ultimately, it comes down to this, if you're going to get +1 valves, you might as well have the head CNC ported and then blend/polished. Someone that has knowledge in porting and how a head flows and not just opening up everything would be best. Even after all that work, someone can throw on a VE head and still outflow and rev your motor.

[MadScientist]

I might do double guides instead of the shim.

explain this...

And also the head flow depends on S13 or S14/S15, and yes the VE head is great but lets stay with what he is currently working with.
This can be argued to death but IMO the S13s High Port head is better for Drag, and the S14/S15 is better for Track, and the VE is just all the issues from prior SRs being corrected.

[stevecorrado88]

Because you're running a turbo capable of 500ish hp. Santos revs to 8100 with a turbo quite a bit larger. You just don't have enough CFMs in the 3071R to pull off 8500 or higher. If the DET head was more efficient, maybe, but it doesn't flow all that well compared to other 4cyl heads.

Ultimately, it comes down to this, if you're going to get +1 valves, you might as well have the head CNC ported and then blend/polished. Someone that has knowledge in porting and how a head flows and not just opening up everything would be best. Even after all that work, someone can throw on a VE head and still outflow and rev your motor.


Ve heads are way more money then what I might be about to do.

[stevecorrado88]

explain this...

And also the head flow depends on S13 or S14/S15, and yes the VE head is great but lets stay with what he is currently working with.
This can be argued to death but IMO the S13s High Port head is better for Drag, and the S14/S15 is better for Track, and the VE is just all the issues from prior SRs being corrected.


Here is the link I read about the double valve guides.slotted rocker arm shims? - SR20 Community Forum - The Dash (http://www.sr20-forum.com/all-motor/53841-slotted-rocker-arm-shims.html)

[jr_ss]

explain this...

And also the head flow depends on S13 or S14/S15, and yes the VE head is great but lets stay with what he is currently working with.
This can be argued to death but IMO the S13s High Port head is better for Drag, and the S14/S15 is better for Track, and the VE is just all the issues from prior SRs being corrected.

I understand he is working with an S13 DET head, but he needs to be fully aware of the cost of having a head done right vs just slapping shit together. You can't polish a turd.

The VE head is more than just a rectification of prior issue with DE/DET heads. However, it is not a cheap initial investment but you'll never have to worry about broken/tossed rocker arms and/or the infamous shim hunt ever again.

Ve heads are way more money then what I might be about to do.

Be ready to spend close to 2k+ for a quality built head. Machine work is not cheap unless you can do it yourself.

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Because you're running a turbo capable of 500ish hp. Santos revs to 8100 with a turbo quite a bit larger. You just don't have enough CFMs in the 3071R to pull off 8500 or higher. If the DET head was more efficient, maybe, but it doesn't flow all that well compared to other 4cyl heads.

Ultimately, it comes down to this, if you're going to get +1 valves, you might as well have the head CNC ported and then blend/polished. Someone that has knowledge in porting and how a head flows and not just opening up everything would be best. Even after all that work, someone can throw on a VE head and still outflow and rev your motor.

you can take the 30R up there the boost will fall a little but power can be made. with a 30R on several SR's we are taking them to 8K all day.

mine i limited at 8100 because i dont have my solid lifters in yet but best believe once i do i will be taking it to 9-9500 all day!

like others said if your gonna build it then build it.
i left my head alone because im going all out on the head i am building.
i made plenty of power with almost nothing. which is why i said to save your $ keep it simple

[MadScientist]

You can't polish a turd.

You can actually, but its still a turd.

The Twin Guide mod... I dunno... if you rebuild everything and its done correctly you won't have this issue anyway. I use RAS in my head and like I said, everything is tested, fitted, checked, double checked... just do it right! Oh and if you go with Solids you will need to re-shim after break-in. My machinist made sure when he tested the shims to match the valves so everthing is even and clear across the board... it took about 2 weeks overall.