Project: Building a SR20DET Head to rev 9000K+ [PICS HEAVY]

Post by **URAS** » Tue May 15, 2007 6:28 pm

redtop91 wrote:The only problem I've heard with RAS is that some of the higher end ones chip.

They would only chip if there is another problem, there is never normally meant to be excessive contact between the rocker stoppper and the rocker. To chip a RAS the rocker must be bouncing way to much.... the RAS are not designed to cure valve train faults.

Post by **juZz** » Wed May 16, 2007 5:05 am

Have you guys machined more valve clearance to pistons with highlift (11.5mm) cams?

Post by **URAS** » Wed May 16, 2007 7:53 pm

juZz wrote:Have you guys machined more valve clearance to pistons with highlift (11.5mm) cams?

no need

Post by **Slipstream** » Thu May 17, 2007 3:18 pm

ILikeMy240sx: What are your measurements for valve stem height? Just wondering if they are diff from the S15/S14/S13 manuals or not.

Post by **juZz** » Fri May 18, 2007 10:39 am

URAS wrote:
no need

What if i go for some overlap?

How much have you tested for lift and advance combinations?

And how much would you recommend advancing/retarding intake/exhaust for a large turbo to spool up good?

Thanks in advance

Post by **DrifterProdigy85** » Sun May 27, 2007 6:19 pm

Speaking of Valve Float. Heres what i did when over revved (missed shift) to 8krpm with stock valve springs, aftermarket cams, and HLA. Just another reason to run Stiffer Valve Springs and Solid Lifters. Had RAS but there wasnt any saving it when the valves were floating like mine did.

Whats funny is my built head comes out the shop this Friday or Saturday but now i gotta wait till the block gets built now. Definitly going Solid Lifters on the new Head. Oh well, Live and Learn.

Post by **S13FASTBACKSR** » Mon May 28, 2007 6:53 am

daaaaaaaaang that is naaassty

Post by **C - ROD** » Mon May 28, 2007 7:22 am

that really sucks!

Post by **DrifterProdigy85** » Mon May 28, 2007 10:40 am

I look at it as an opportunity to build the block now instead of later. Eliminates me having to do work twice.

Post by **C - ROD** » Mon May 28, 2007 10:54 am

im doing my block now, then my head in a few more months

Post by **redtop91** » Mon May 28, 2007 11:12 am

I've never done block work before though.

Post by **silentvoice71** » Mon May 28, 2007 12:45 pm

DrifterProdigy85 wrote:Speaking of Valve Float. Heres what i did when over revved (missed shift) to 8krpm with stock valve springs, aftermarket cams, and HLA. Just another reason to run Stiffer Valve Springs and Solid Lifters. Had RAS but there wasnt any saving it when the valves were floating like mine did.

Whats funny is my built head comes out the shop this Friday or Saturday but now i gotta wait till the block gets built now. Definitly going Solid Lifters on the new Head. Oh well, Live and Learn.

mm

hahaha in the words of homer mmMmMmMm {drools} valves lol thats looked fun.

Post by **C - ROD** » Mon May 28, 2007 7:37 pm

so is there any hope for ur head, like can it be machined or are u going to have to replace the entire thing?

Post by **DrifterProdigy85** » Tue May 29, 2007 4:24 am

I have a spare head being built at the moment and get it this friday. The is no hope for the stock head. Compression Chamber is too broken up. Also cracked the piston and ****ed up the cylinder wall. Im just gonna build a new block to hold the 600whp that ill be putting to it by winter.

Post by **LANOI** » Wed May 30, 2007 9:01 am

I read the rocker arm on stock sr are weak and can break easily when red lineing any truth?

Post by **boj240** » Wed May 30, 2007 11:21 am

yeah thats why its really good to do the rocker stopper upgrade and plus easy to do and cheap

Post by **DrifterProdigy85** » Wed May 30, 2007 1:08 pm

Ive got Greddy Rocker Arm Stoppers on mine and to be honest, i doubt they did anything just because they dont fit tight enough to the Rocker to not make it jump off. I think it all goes back to Valve Float. If the valves float, then the springs arent moving much and when the cam comes in contact with the Rocker, it can make the shims bounce which ends up throwing the Rocker. I could be wrong though.

Post by **C - ROD** » Wed May 30, 2007 6:01 pm

what kind of valve springs were u running? im assuming stock if u had enough valve float to make the rocker jump off

Post by **spider_slayer** » Thu May 31, 2007 3:13 pm

DrifterProdigy85 wrote:Speaking of Valve Float. Heres what i did when over revved (missed shift) to 8krpm with stock valve springs, aftermarket cams, and HLA. Just another reason to run Stiffer Valve Springs and Solid Lifters. Had RAS but there wasnt any saving it when the valves were floating like mine did.

Whats funny is my built head comes out the shop this Friday or Saturday but now i gotta wait till the block gets built now. Definitly going Solid Lifters on the new Head. Oh well, Live and Learn.

wow i'm seriously impressed.

Post by **DrifterProdigy85** » Thu May 31, 2007 4:50 pm

Stock Springs. Only reason the Rocker jumped off was because the Keepers on one of the Exhaust Valves came off. Definitly dont rev above 7500rpm on stock springs. Im proof that bad things happen. Its all for the good anyways. Mazworx is building my block. Already have a built head waiting. Pretty much gonna have a totally new motor now.

Post by **C - ROD** » Fri Jun 01, 2007 3:53 am

getting it done at Mazworx, im sure that thing will be nice

Post by **thang nguyen** » Wed Jul 11, 2007 3:17 pm

So what's the status on this project???

Post by **spider_slayer** » Thu Jul 12, 2007 5:22 pm

i'm thinking the same thing.

school is over.

time for an update.

Post by **otterman** » Sat Aug 25, 2007 6:42 am

So.... did this SR ever run or what?

Post by **redtop91** » Sat Aug 25, 2007 6:43 am

He said it was running. And LOL @ your sig.

Post by **otterman** » Sat Aug 25, 2007 11:55 am

Why is there no pics or vids of the car running yet?

Post by **IanS** » Sat Aug 25, 2007 3:27 pm

otterman wrote:Why is there no pics or vids of the car running yet?

because he hasnt converted his wheels to legs, yet.

Post by **Geno750** » Sat Aug 25, 2007 7:28 pm

LANOI wrote:I read the rocker arm on stock sr are weak and can break easily when red lineing any truth?

Sure, when you install rocker arm stoppers.

boj240 wrote:yeah thats why its really good to do the rocker stopper upgrade and plus easy to do and cheap

No, rocker arm stoppers + hla's = broken rocker arms, see below.

DrifterProdigy85 wrote:Ive got Greddy Rocker Arm Stoppers on mine and to be honest, i doubt they did anything just because they dont fit tight enough to the Rocker to not make it jump off. I think it all goes back to Valve Float. If the valves float, then the springs arent moving much and when the cam comes in contact with the Rocker, it can make the shims bounce which ends up throwing the Rocker. I could be wrong though.

those greddy RAS are likely the reason your rocker arm broke instead of it just poping free and sitting intact in the head.

To avoid all of this people like ILikeMy240sx, and myself went with sla's

Post by **ILikeMy240sx** » Sun Aug 26, 2007 1:32 pm

hey guys. Car is running fine and it has been running with Solids since my last post. Few things that happened....

1) The head that I received in the mail had bent cam oilers from shipping which I obviously couldn't tell because it was bent slightly. However my cams were able to tell. So my cams broke off the tip of the cam oilers forcing them to make its way down the front cover and in my oil pan.... Sounds sweet haha.

1a) Due to the front part of the cam oiler being knocked off, it starved oil to the intake cam which resulted in metal to metal contact DURING my drive back from Tennessee (NICO meet) to Michigan... yeah... 8 hours of metal to metal contact resulted in #2 lobe on the intake cam to have about 3mm of metal shaved off and rocker arm being destroyed beyond recognition.

1b) The good news is that nothing major damage occurred... just the rocker arm and the cam. The broken oilers have been fished out by dropping the oil pan.

2)So I replaced by intake cam with 260 cam instead of 270 because 270/270 setup was wayyy too much for the turbo I am running (gt2871r .64a/r) and that setup resulted in my full boost occurring at 4500 RPM. 260/270 setup is not much different in terms of when the boost kicks in but I do feel a bit more low end punch. I should have went with 260/260 setup instead... oh well.

3) Also when I measured the valve clearance, some of the clearance opened up a bit but none of them except for couple were out of the recommended clearance range. But I re-shimmed them to .004" clearance and have been running fine since.

Post by **S13FASTBACKSR** » Sun Aug 26, 2007 2:05 pm

taesoo sounds great man..what do you suggest as far as cam setup for a gt3071r .63 with tomei solid lifters? thanks bud

Project: Building a SR20DET Head to rev 9000K+ [PICS HEAVY]

Re: (redtop91)

Re: (juZz)

Re: (ILikeMy240sx)

Re: (URAS)

Re: (URAS)

Re: (DrifterProdigy85)

Re: (C - ROD)

Re: (DrifterProdigy85)

Re: (URAS)

Re: (LANOI)

Re: (DrifterProdigy85)

Re: (C - ROD)

Re: (thang nguyen)

Re: (otterman)

Re: (otterman)

Re: (LANOI)

Re: (ILikeMy240sx)

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