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What's up, guys and gals?

Long time, no post. I used to have the screen name 1996man on this forum but it has been several years ago and I can no longer get access to that old email so I created a new screen name so hopefully I can start interacting with this great community again.

Let me see if I can get all the facts out there. I own a 1996 LT4 coupe that unfortunately has been sitting for years. I am now finally at a point where I can start to restore it and I would like some help with my planning of this build. I wish I could go all out but budget is still a minor concern here. I had a LT4 Hotcam from many years ago that I never got around to installing before. It is brand new, still wrapped up with oil and should still be 100% useable so I would like to base the build around that. I also really want to use the scorpion 1.7 rockers. I have read a lot about the Hotcam/1.7 rocker combo and I have decided that this is the route that I would like to go.

I am trying to go with a pretty mild but tried and true proven build but I still have a couple questions and I am hoping all you freindly experienced people can help me put together a list of part numbers that I will need for this project.

I will list the part numbers I have so far and hopefully you can help me figure out what else I need in order to do this job correctly.

As mentioned before, I am going with the LT4 hotcam PN#24502586
I am also going to go with the Scorpion 1.7 Rockers #1026- these use the 7/16 studs which I am told is what the LT4 uses from the factory.
Speaking of studs, am I reading this correctly that these 7/16 studs are smart to replace with ARP hardware? If so, what ARP part number would I need for these?
Any other ARP hardware that would be good to use? I hear nothing but good things about them so depending on what the cost difference is, I wouldn't mind getting them where needed.
As far as the valve springs go for this project, I am told by many people that the-Comp Cams Springs- PN#26918 will handle the combined lift of the LT4 Hotcam and 1.7 rockers.
After doing a lot of research, a lot of people are recommending the-LS7 lifters #12499225.

Another question I have is pushrods. I know there are several guys running standard pushrod length with the 1.7 rockers and LT4hotcam but I am told that even using the LS7 lifters will affect the pushrod length needed. Does anybody know exactly what length I would need with this combo or how I would even do the math to figure that out? Are hardened pushrods nessecary for a 400-430HP build? If so, thats fine but what brand should I go with? Does ARP make these as well or is it better to go with another brand? ANy part numbers would be greatly appreciated.

I am told by many people that going with the somewhat expensive-LT4 Extreme duty timing set PN#12370835 is a very plug and play option and should hold all the power I have planned

I know from reading several build threads on different forums over the years that the SVO #30 injectors used to be popular for this type of build. Would these be enough for this build and power level?
I went to go find part numbers on those but was finding several different numbers. Are these still the best route to go? What is the current part number that you would suggest?

Is PCM4Less still the best place to get a mail order tune for this build? What do those usually run?

I think I will start a seperate thread about the optispark. Too many variables to discuss here

I have not seen much mentioned about the balancer in these build threads. Any suggestions on what to go with here?

I had an electric waterpump on this car before it went down. I think it was a Meizer? Do they still make products for the LT1/4?

Is there any need to do a fuel pressure regulator with this build or would that all be taken care of with the mail order tune?

I am going to start a seperate thread about some gasket questions I have

I dont' want to spend a ton of money sending my heads out to AI or LE because I dont' really think they need that much more flow for the valvetrain that I have planned but if I have to have a local machine shop shave them for instance, would it be possible for them to do valve seals and I still get to keep my lighter sodium filled valves that came on my LT4 heads from the factory?

I think thats all the questions I have for now but I will probably think of more. Once I crack open the old motor and have a better idea of what I am dealing with, I will probably start a new build thread.

Thanks so much in advance! I am really looking forward to this project and hope you guys can help me figure it out.--
 

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well the first thing that struck me was that if you decide to install that hotcam
Chevrolet Performance LT4 Hot Cam Hydraulic Roller Camshafts 24502586

and the 1.7:1 ratio rockers your definitely going to need to install different valve springs,
those Comp Cams Springs- PN#26918 will require the heads be machined in many cases,
keep in mind the increased rocker ratio and new cam will push valve lift to at or even over what the valve spring lift is designed to handle,(have your machinist verify that)
and have the spring bind and valve seal clearances checked, probably that will require different valve shims, retainers keepers and machining the valve guides and yes you may require ARP rocker studs and a rocker stud girdle to get decent long term durability,
and more than likely remove the heads and have the rocker geometry and clearances checked carefully, and your darn sure going to need the push rod to cylinder head clearances carefully machined for greater clearances also.
don,t ignore checking piston to valve clearances when you check and degree in that cam.
and yes I would suggest a 36 lb injector and a good dyno tune, an adjustable fuel pressure regulator and a fuel pump that provides about 450 lt per hour
as always, before you begin any project think things thru...take the time to do some research and ask questions and never assume you can skip checking clearances,
and yeah,
skip reading the links and you miss a great deal, of useful related info

http://garage.grumpysperformance.com/index.php?threads/replacing-a-c-4-fuel-pump.33/

http://garage.grumpysperformance.com/index.php?threads/how-big-a-fuel-pump-do-you-need.1939/

http://garage.grumpysperformance.com/index.php?threads/calculate-fuel-injector-size.1200/

http://garage.grumpysperformance.com/index.php?threads/degree-it-in-correctly-and-get-it-to-last-cam-install-info.90/

http://garage.grumpysperformance.com/index.php?threads/valve-train-clearances-and-problems.528/

http://garage.grumpysperformance.com/index.php?threads/sellecting-valve-springs-and-setting-up-the-valve-train.181/

http://garage.grumpysperformance.com/index.php?threads/checking-piston-to-valve-clearances.399/

How To Build a 475 Horsepower LT4 Powerhouse Engine

This One Goes To 11: Cranking Up The LT4 With Lingenfelter

http://garage.grumpysperformance.com/index.php?threads/lt1-lt4-1992-96-corvette-engine-related.14574/#post-77392

http://garage.grumpysperformance.com/index.php?threads/lt1-vs-lt4-corvette-engine-parts-differences-useful-links.13141/#post-68543

http://garage.grumpysperformance.com/index.php?threads/lt1-cooling-info.2538/#post-6583

http://garage.grumpysperformance.com/index.php?threads/want-some-basic-lt1-related-info.1127/#post-2248
 

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8,453 Posts
any progress or issues?
 
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