Calderone

uv,sorry im not getting it .-
What does the new bolts has to do with the bench ?
I have no head bench here ! yes i will buy a set of ARPs as well.-

MK 82

You said you wanted the best result. In my opinion, that is how you do it.

Calderone

yes,but taking those springs off is very traumatic for me
im sure the Loyd Elliot Method is good as well and i have found other sites that mention that method as well.-
Thanks a lot anyway

ultraviolet70

By bench I just mean the cylinder head is off the car and sitting on your work bench or kitchen counter or what ever you might be using to work on.

New head bolts require a rolling in process which requires you to torque head bolts to spec in the proper sequence and loosen this needs to be done a minimum of five times and you need to use a junk head gasket until you're ready for the finall pass and leaving the head in place.
What this means is you can do as I did

http://forums.corvetteforum.com/c4-t...n-start-2.html

Look at post #29

I installed my test springs on valves for cyl #1 while the head was off the car. Installed the head with my cheap head gasket for rolling in the threads, torqued and loosened the head bolts 3 times, on the fourth pass I stopped before loosening the head bolts and measured for my correct pushrod lenght. I then loosened the bolts and removed the head as I had to anyway to install my intended head gasket for final assembly, with the head on the work bench it was easy to swap the test springs back for the correct valve springs. Installed the correct head gasket, set the head on and torque that basterd down.
Any questions feel free to PM me.

MK 82

A quote from Lloyd Elliot.

"I like the springs better than changing lifters as the lifter can have a different ht where the pushrod sits and make the measurement wrong unless using testing pushrod length with the same lifter you will run."

Calderone

Thanks for the advice guys,im learning a lot.-
It will be a blast !

Calderone

Oh guys btw ....what can affect my measurements ?
what's the variable ? for example ...can i use the same length pushrod that maybe another member uses ? if somebody has AFR+195s and LPE219 ...can i use those same pushrods ? or every build has to be measured ?
thanks

ultraviolet70

What can affect lenght, well to name a few off the top of my head
Block deck height
Cyl head
Valve lenght
Rocker arms
Lifters
Cam
Head gasket
Lots of variables, measure, don't take chances

Weav's vet said he sees 7.100 seems to be common lenght for guessing without checking, and where this might and probably does work for alot that would be almost two tenths of an inch to short for my application.

You're talking about spending alot of money and time on this build, don't cut corners.
It cost me less than $20 for the adjustable push rod lenght checker and the two test spring and added less than 10 minutes to god knows how much time invested in this build, build.

Calderone

Yes, hehehe u got me cutting corners
I already bought a mockup rocker arm and the adjustable pushrod.-
I will do things right,where did you buy those test springs ?

are this OK THEN ?
http://www.summitracing.com/parts/MOR-62380/

Or do i need a pair only ?
http://www.summitracing.com/parts/CCA-4758-2/

ultraviolet70

You only need the pair, the comp cams ones are actually the same ones I used. Technically though they are nothing more than low tension springs that you could pick up at any hardware store, so if you already have all your parts and don't need to make any orders with Summit/Jegs I wouldn't make an order just for those, but if you have an order to make I'd say go ahead and get them as you're not going to save anything at the hardware store.

Calderone

thanks !

85vet

No, it can happen with any cam - you have to know if any advance is ground into the cam and install it accordingly.

If I recall correctly - the combo can run high 11's to mid 12's. Depends on your car's setup, no two cars are identical.

Good luck with the build!!!!!

Calderone

You got me scared,maybe my zz4 cam is installed wrong !
but the car runs fine ! ...sorry for the stupid question but what's "advance ground into the cam" ???? How can i know that ? its like a "preload" so to speak ?
I would really like to read more about this matter to avoid mistakes.-
thanks !

tpi 421 vette

Alot of cams are ground with a 4 degree advance. That is to give the car better bottom end power. Where you are changing cams in the car, it would be real hard to degree the cam with the engine in the car. Not saying it can't be done, but it would be a PITA. Plus you would have to use a real small degree wheel, which aren't as accurate. Degreeing a cam on the engine stand is a whole different story, and you have room for a large degree wheel. Personally swapping cams in the car, I would probably just line up the timing marks and call it good.

Calderone

Yes when we installed the ZZ4 he aligned some little points...is this what we are talking about ? maybe my cam was always in wrong degrees,but no i dont think so ..but im curious

Calderone

Sorry to bump this old thread,im about to do the cam swap
and i was reading about the 4 degree already in !!!
this are the specs on the box,my engine is on the car and i won't be taking it off.
help guys i already have all the parts here,im only out of pushrods,im waiting to measure
thanks !

STL94LT1

Calderone, unless I'm reading something wrong it doesn't look like your camshaft has ground-in advance.

Calderone

Thanks,must be a silly question but its the first time im exposed to a real performer cam
last time i upgraded from stock to the ZZ4,so now the ground-in was a possibility like 85vet said,but here i included the specs of my current grind,i guess if the advance grounded in was there ..maybe it has to be on the spec sheet / box ..am i right ?
Thanks

GREGGPENN

No advance is ground into that LPE cam. FWIW, it seems like I heard/read that they used to have advance ground in, but not any more,,,now that Comp is grinding them.

You can install it either way, straight-up or advanced. Advanced with provide more low/mid power. Straight-up will shift the powerband upward.

Pick your poison.

NeurOn

sammy..you are doing great things on ya vette...but don't be rush..take it easy and everything will be ok...
BR, Seba