pr1689

I need to order pushrods for the engine rebuild. Here is what I have so far:

87 350 bored 60 over
flat top hypereutectic pistons
GM roller lifters
comp cams roller rockers 1.5 ratio 3/8 stud
ZZ4 cam
ZZ4 heads, aluminum, guide plates, ported, casting #10088113
TPIS big mouth intake
ASM large tube runners (have to use stock for now until they come in)
24lb injectors
700R4 tranny w/shift kit
3.73 posi rear
aluminum drive shaft
msd6a
Hooker 2055 headers jet coated on the inside and out
hi-flow cat
3" from cat back to exhaust
ARP head bolts
ARP intake bolts


I don't know what length or type of push rod to get or what kind to get? Anybody know the answer to this? How about a part# and from where?!

On another note, anyone have a rough idea of what kind of HP we're going to get out of this setup? I'll have to find a shop with a dyno so I can have exact numbers, but I'm a little ways away from that right now.

Thanks for any advice and suggestions!

Pat

ljnowell

Lots of people simply order stock length pushrods and run with it. The correct answer to your question is that you need whatever length you need. You need to purchase a pushrod length checker. Its basically an adjustable pushrod. Then you dummy it up as a pushrod and check for geometry at different lengths until you get it right. There are a couple threads here that cover pushrod geometry if you look it up, you will find it.

pr1689

Hey thanks for the information! I will see what I can find!

Thanks again,

Pat

Viprklr

iTrader: (5)

On an off chance (woulda saved me some cash), check your valvetrain geometry using one of your stock pushrods. Doesn't cost you anything but a couple minutes of time.
I should've done this first before buying my checker.

pr1689

That's a good thought, however, when the head had cracked, all the radiator fluid had mixed with the oil and I'd feel a lot more comfortable buying new since everything in the engine is new. Plus with how hot the engine had got, I think it's probably best I just get new. Otherwise, I would definitely give that a whirl. I may do that just for grins, but I will definitely replace all with new anyway.

To be honest I hadn't even considered that before. I figured with going from a flat tappet cam to a roller cam and roller lifters, plus new heads, (albeit all are considered OE from GM) I figured the length would be different anyway.

Thanks guys for all the suggestions! This is such a wonderful board!

Pat

GuitarJunki17

iTrader: (1)

Getting a new set of pushrods for the peice of mind alone is worth it, especially with a built setup like that.

I second the pushrod length checker, but as stated try one of your stock length first. Get a pushrod length checker that is in the same size range as the stock ones, they vary greatly in sizes, and you may get one that doesnt adjust to the length you need. (for simplicity's sake, say you have 7.5 inch stockers, get a checker with a range of 6.75-8)

Kevin91Z

iTrader: (1)

I highly recommend Manley pushrods. You can get them at Summit or Jegs or your favorite local place. Stock length for a roller camshaft is 7.2" and a flat-tappet camshaft uses 7.8".

pr1689

I ordered a checker from Comp Cams last night as well as a set of 7.2 length pushrods. After reading other posts and speaking with Comp Cams, I decided to order the set and will use the checker and if it comes out to 7.2, then great, otherwise I'll send them back and get the correct length. Hopefully that will be the length I need.

I'm not going to rush through the build although its difficult not to!

Thanks again for all the great advice! I'll post how the build is going and see if I can't get some pics up of the completed build! Then after installation and the exhaust setup, I'll see if I can't get some sound clips too.

Thanks again,

Pat

Viprklr

iTrader: (5)

As I stated in my original post.....If you want to know if your stock size would work just try one of your original stock pushrods. It's just to check geometry not to run the engine.