Biochem

When I did my engine swap, I had some longer (0.001" or something like that) pushrods and it called for them in the Edelbrock manual. Why? I only ask because my idle sucks. It won't go less then 850rpms and is really rough. It did something similar (but more extreme) when I put these same rods in my LG4... and went away when I put the stock length back in.

I have 1.6 rollers and a Comp262 cam too.

------------------
1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock... all the suspension stuff... 9-bolt posi disk is in... K&N filter... 93 octane...

-=ICON Motorsports=-

TRAXION

You don't need longer pushrods. Buy a set of Trick Flow chromoly 7.200" pushrods. They work perfectly.

Tim

------------------
TRAXION's 1990 IROC-Z
Best Time = 12.587 @ 107.97mph (1.710 60ftr) on the long runner setup.
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels. Stock Wheels. No Weight Reduction.
Gunning for NA 11's with the MiniRam II and Hooker LT Headers.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

FastBroker

You NEED .100" longer pushrods for the Edel heads because their heads are about .100 thicker than iron heads to givethem more pressuremounting material to help the softer aluminum seal better...



[This message has been edited by FastBroker (edited October 09, 2000).]

MikeH

iTrader: (10)

Its apart of valvetrain blueprinting. Setting up the right length pushrod will give you more miles out of your heads/guides in the long run.

The pushrod length is correct when the witness mark on the valve tip is approximately 1/3rd of the way in from the inboard side with the lifter on the base circle of the cam. Total travel of the rocker arm should be across the middle third of the valve stem tip, anywhere from .030 to .050 inch in width.

------------------
Black 90 IROC, L98, A4, 323 gear. SuperRamed 406 in the works!

FastBroker

Yep. and if the new heads are .1" thicker and the pushrod length was correct before you changed the heads, you need .1" longer pushrods...

Biochem

That is my thought too. I was just curious if that could be causing my rough idle, but I don't think it is. Thanks guys.

Jarod87IROC

Those are the exact same pushrods I'm using with my Performer 6085s.



------------------
87 IROC
350 TPI 5-speed
- Edelbrock Aluminum Heads, LPE 219 Cam, Super Ram, SS Wheels, Graphite Leather, etc. Click here to see the rest.

-=ICON Motorsports=-

Hurtin4Hp

The way I read the instructions that came with my Edelbrock heads was that you need the longer pushrod if you reuse the stock or stock type rocker. If you use an aftermarket rocker you should use the standard length pushrod.

Jarod87IROC

Yep, I believe Hurtin is correct. It depends on which rockers you use, I remember reading that now that he mentioned it.

TRAXION

Who here who made the comments that you NEED 0.100" pushrods actually HAS edelbrock heads or heads that have a thicker deck? I'm waiting .... hohum.

I've talked with several Edelbrock owners already. A couple bought the longer pushrods to find out that they aren't needed and actually THROW THE GEOMETRY off. FURTHERMORE, I have AFR heads which have a seriously thick deck. Guess what? Stock length pushrods are the best fit for these heads. My geometry is perfect. I am talking real world experience here not theory.

In theory I understand where you are coming from ... but, at least have some experience to back it up.

Tim

------------------
TRAXION's 1990 IROC-Z
Best Time = 12.587 @ 107.97mph (1.710 60ftr) on the long runner setup.
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels. Stock Wheels. No Weight Reduction.
Gunning for NA 11's with the MiniRam II and Hooker LT Headers.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

406TPI

iTrader: (1)

Stock length pushrods on my 6085 heads.....works just fine

Ski89Z28

The instructions for the Edelbrock 6085 heads stated several different type of aftermakarket roller rockers and said you WILL need +.100 over stock length 7.200".
Then they give some more aftermarket roller rockers and stated that THEY GET STANDARD LENGTH PUSHRODS 7.200". I don't know the name brand names, sorry, but this is real world experience and NOT "in theory" since I just installed them this past May. The ones I installed were the Crane Gold Race Rockers, non-self aligning, narrow body for centerbolt valve covers and when I called Edelbrock they said these are the ones they recommend but it wasn't shown on the paperwork cause they haven't updated it!
One last thing is that they say to ONLY use 1.5 ratio RR. This is because the 1.6 ratio RR will wear down the guideplates but you can use 1.6 ratio RR on the 6085 heads. Just kept tabs on the guideplates. And as always use HEAT TREATED pushrods with heads with guideplates.
TRAXION I have alot of respect for you and you have alot of knowledge ( you car times prove that) but you weren't totally right. Hurtin4Hp was right.
It depends on the type of roller rocker NOT RATIO and why different type roller rocker? I have no idea you need to contact Edelbrock.
I hope this helps clear the air.

BTW, one last thing, the springs on these heads (6085) will bind with a cam of .560 lift or higher.

Good Luck!


------------------
89 IROC 350 Auto
TRUE DUAL Exhaust
Edelbrock Performer Aluminum Heads
ZZ9 Cam
TPIS Level 5 Chip
14.01 @ 97.0mph with 2.77's gears

TRAXION

ski89Z,

Understood. I missed hurtin4hp's post. That makes sense because everyone I talked to had aftermarket roller rockers ... go figure ... if you have aftermarket heads I bet you would also have aftermarket roller rockers

My main goal was to hear from people with real experience ... not just theory. In many cases theory just does not jive with the real world ... that sux but sometimes it happens that way. Anyhow, I'm glad that's cleared up

Tim

------------------
TRAXION's 1990 IROC-Z
Best Time = 12.587 @ 107.97mph (1.710 60ftr) on the long runner setup.
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels. Stock Wheels. No Weight Reduction.
Gunning for NA 11's with the MiniRam II and Hooker LT Headers.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

Jarod87IROC

Now where'd you get that info from? I was told these springs are good up until .600" lift. And with my LPE 219 cam and 1.6 RR's I am right at .560". I've got close to 3k miles on them with numerous 5k+ shifts and I have yet to experience any problems. Are you stating this from experience or did someone just tell you that? Enquiring minds want to know.

Ski89Z28

Jarod87IROC, I should have said "I THINK" my mistake. However I did talk to a tech from Edelbrock on the phone (going on 6 months ago) and I thought he said it was good to .560 lift BUT now you have me wondering and I'm not sure now what I heard. Maybe he did say .600 lift ... at this point I should call them and ask again. I'll get back to you on this issue earily next week.
Sorry.

Jarod87IROC

Ok, well for my sake let's just hope you're wrong. I know I read .600" and I doubt they would actually rate them higher than than what they can handle, usually it's the other way around. But you never know.

Hurtin4Hp

The Edelbrock rep I spoke with a few months ago definitely said up to 0.560" would be safe.

P J Moran

Here's my experience:

When putting my combo together, I e-mailed Edelbrock for their guidance on this very matter. I am using Comp Cams Magnum roller tip rocker arms. They insisted that I needed 0.1" longer-than-stock pushrods.

I took their advice, and have had no problems whatsoever. However, I haven't pulled a rocker cover to inspect the wear pattern to see if it's centered. With roller tips, would I even see a pattern?

------------------
'87 IROC 5.7l TPI - original owner!

Biochem

Well, I hope to answer this once and for all this weekend. I ordered some stock length pushrods. For the record, I have Crane Energizer 1.6 roller (tiped) rockers. I doubt I will see any wear pattern from them on the valves though...

------------------
1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock... all the suspension stuff... 9-bolt posi disk is in... K&N filter... 93 octane...

-=ICON Motorsports=-

Biochem

Well, the idle isn't perfect, but it is a hell of a lot better then it was. Stock length pushrods with 1.6 rollers with the Performer heads is the way to go...

------------------
1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock... all the suspension stuff... 9-bolt posi disk is in... K&N filter... 93 octane...

-=ICON Motorsports=-

Ski89Z28

With that Comp262 cam you won't have a smooth idle just a little lopey.
Good Luck!

Scott C

What about Edelbrock 6085 heads, GM/LT4 1.6 roller rockers and NO GUIDEPLATES?? Is this ok? I had SDPC add the heads, rockers and cam to my new 350 and it was shipped without guide plates. I'm just wondering if there will be a future problem?

------------------
'92 RS, ZZ4 10:1 350, Edelbrock 6085 heads, Crane 208/214 467/482 cam, GM/LT4 1.6 true roller rockers, Holley Projection TBI intake, Holley 670 TBI, SLP/Jet-Hot 1-5/8" headers, Catco 3" cat, Flowmaster 3" catback, Hughes 2500 stall converter, stock 700R4, Auburn Pro posi w/3.42, 17x9" SS rims w/BFG tires, Medium Quasar Blue w/white SS stripes, 48,000 miles....

Biochem

I am pretty sure even having self aligning rockers, that NOT having guideplates is a BAD thing...

IROCZZ3

With aftermarket heads...

Self aligning rockers= NO guideplates

NON self aligning rockers= USE guideplates AND hardened pushrods.

So if those GM 1.6 roller rockers are self aligning (I believe they are) then SDPC did the right thing and shipped your heads without the guideplates. You'll be ok.

FWIW, my AFRs come witht guideplates and specifically say to use only theirs. So I decided to run Crane Gold non self aligning narrow body roller rockers and hardened pushrods...no problems. HTHs


------------------
1989 IROC-Z, ZZ3 shortblock with some bolt-ons.
13.20 @ 108.69, 2.2 60'

Jarod87IROC

You don't want guideplates with self-aligning rockers. When I put my self-aligning Crane Gold 1.6 rockers on my Edelbrock 6085 heads I made sure to pull the guideplates off.

JakeJr

I don't usually post here since I've got an 86 Vette, but since I'm running Edelbrock 6073s I thought I share my experience.

I read the literature that came with the heads and it said that with stock (sled-type) rockers .100 longer pushrods would be needed, but that with aftermarket roller rockers the stock length pushrods would be fine.

Not to take any chances I bought a pushrod length checker and came up with 7.195 so I ordered a set of Trick Flow 7.200" with .080 walls. These are the standard length pushrods for the hydraulic roller.

Also, when I ordered the heads I chose the option to go with the bigger diameter springs which I was told were good for .600 lift. I checked the seat pressure and it was 125, which is the max recommended for the ZZ9.

Using CompCams Magnum 1.6s and the ZZ9 I'm still well under the max lift those spring can handle.

Hope this helps.

Jake - Not to be confused with my namesake

------------------
1986 Corvette Coupe, 415 CID, Edelbrock 6073s, ZZ9