Cascade Crew

townaj · Posted: Fri Feb 26, 2010 6:44 am Post subject: Gear drive, x-pipe and cam

So I'm gonna be pullin my engine back out of my car to repaint it and do some maintenance. My old dipstick somehow broke off into the oil pan so I'm going to fish that out. While its out I was thinking about replacing the timing chain with a gear drive. Anybody have any experience with these? Also I was going to buy an x-pipe kit from summit and try to redo my exhaust. Again. So where would be the best place to put the x? In the front, middle, back? Does it really matter? And lastly I was wanting to go with a bigger cam. I just love the lope. Right now I have a GMPP cam with about .480 lift. I don't know duration though. What would work with a 383 stroker? I don't want to have to clearance anything else. Thanks guys.

91RSVert · Posted: Fri Feb 26, 2010 7:55 am Post subject:

Only thing I can help with is that I have read you can not run a geardrive timing set with an ecm. If your carb, your ok.

If the cam you have now is the zz4 cam, let me know after you pull it out Wink

townaj · Posted: Fri Feb 26, 2010 11:29 am Post subject:

Yeah i have a carb setup. And I took out the whole computer. But now im not so sure about the gear drive. People say that it transfers a lot of motion to the valvetrain. And I'm sure you wouldn't want the cam-its hydraulic flat tappet.

Quasi-Traction · Posted: Fri Feb 26, 2010 12:24 pm Post subject:

I'll chime in:

1) I'd avoid a gear drive, no personal experience, but the feedback I've heard is that they're noisey, and (like you said) transfer valvetrain harmonics like a tuning fork.

2) An X pipe can be done if you're ok with having your exhaust hang a bit lower. If your car is or if you plan on significantly lowering, you might reconsider. Just my humble $.02

townaj · Posted: Fri Feb 26, 2010 12:35 pm Post subject:

Ok well then I've decided against the gear drive. But I will be going with the x pipe. My exhaust can't really hang much lower so its no big deal. Im going to go with this one I think http://www.summitracing.com/parts/JEX-XP6/ mostly because its cheap. I still don't know about the cam, I don't know enough about them to understand what would be best. I'm also looking into mech. fuel pumps. Anybody got any input on that?

Quasi-Traction · Posted: Fri Feb 26, 2010 12:44 pm Post subject:

I have a basic run-o-the-mill Napa mech fuel pump, seems to work just fine. If your super-picky or have braided stainless lines and 6 or 8AN fittings, Summit puts out a basic copy of a holley mechanical fuel pump, for like $50.

91RSVert · Posted: Fri Feb 26, 2010 1:05 pm Post subject:

d00012 · Posted: Fri Feb 26, 2010 2:21 pm Post subject:

The gear drive whines similar to a supercharger, noisy for street and too much harmonics for racing apps. Kind wonder why they made them? Yes, they don't stretch like a chain/belt...but it's like buying a fart can...it may sound like it's a racing machine with the supercharger whine, but it's just those silly gears.

From what I've been researching, the cam is dependent on your heads. You can either machine some heads, flow chart them, determine the best cam, and go from there. Or, you can get the same setup as others before you. I would prefer the latter.

Alphius · Posted: Fri Feb 26, 2010 3:59 pm Post subject:

townaj · Posted: Fri Feb 26, 2010 6:12 pm Post subject:

Yeah i was gonna run braided lines since my current line has a major kink in it. I'll look into the summit pump. Would you happen to have the part number for that? And i suppose i should upgrade heads before cam huh Embarassed

. I just have heads off a 72 camaro. At least thats what the numbers said. I was thinking about porting them....but idk if i trust myself with that.

Quasi-Traction · Posted: Sat Feb 27, 2010 11:41 am Post subject:

you may not need to change the heads, but definately check valve size, and make sure your springs can handle the cam you pick out. Might not hurt to put new valve seals on there as well.

townaj · Posted: Sat Feb 27, 2010 11:49 am Post subject:

Heads were rebuilt with oversized valves when i put the motor in so they should be ok as far as seals go. But what do i need to check for the cam? And how would be the best way?

Quasi-Traction · Posted: Sat Feb 27, 2010 11:56 am Post subject:

usually when you buy a cam or cam/lifter kit, it comes with a cam card. I know lunati cams usually have a sugggestion on what spring to run. Never ran a comp cam, so I have no idea if they do.

what you'll want to check for is seat pressure, open pressure, install height, and coil bind. even if you don't by springs from the cam manufacturer, try to get springs that are very similar to what is reccomended.

don't know if you have press-in or screw in studs/guideplates, but that would be a worthy investment if you're pushing past .480" lift. Depending on how much lift you go with, it might be a good idea to have the valve guides clearanced a bit, if not already done.

izcain · Posted: Mon Mar 01, 2010 8:56 am Post subject:

This is a carbed motor correct?

For a 383 they like some thing into the 230's @ .050 for duration it really wakes up those motors well! But with anything larger there will be sacrafices. Better check and make sure your springs can handle more cam as well.

Just throwing a larger cam into something with stock heads sometimes is a recipe for a big pig that has a nice sounding idle but wont hardly get out of it's on way.

What is the whole combinations of the engine in it's current form?

townaj · Posted: Mon Mar 01, 2010 2:35 pm Post subject:

Yeah its a carb motor. The block is a 4 bolt main out of a 1975 pickup. Bored .060 over with scat crank and connecting rods, sealed power pistons, 72-73 camaro heads with larger valves, GMPP cam .480 lift, Weiand dual plane intake-not sure of the number I'll have to check, and an old 650 holley.

If I do get a cam I'll be sure to get springs that will handle it. Heads are just so damn expensive Why me why me?

. Especially once you add all the goodies to them. I'm tryin to get the damn tranny in right now, but now it won't start.

Twilightoptics · Posted: Mon Mar 01, 2010 3:27 pm Post subject:

townaj · Posted: Mon Mar 01, 2010 5:51 pm Post subject:

Compression is pretty high. Its between 9.5:1 and 10:1. Not sure what you would classify as low compression though. I don't remember the deck height off hand but I have it somewhere. Valves are 2.02 and 1.60 I believe.

Twilightoptics · Posted: Mon Mar 01, 2010 6:15 pm Post subject:

9.5-10 is decent for an iron headed SBC.

Definitely need to run the numbers. If your machineshop is anything like ours, half the time they give you the number of the pistons out of the book... which doesn't mean squat depending on heads, deck height, gasket etc.

What's your gasket thickness? Gasket bore? Piston -cc?

townaj · Posted: Mon Mar 01, 2010 7:16 pm Post subject:

Not sure about the gaskets. I got this kit: Fel-Pro QKS2600 But it doesn't have any info on the head gaskets. Guess I should keep better records next time Embarassed

. The head machinist actually sat there and calculated the ratio with me though. The piston cc's I'm gonna have to look up. They are flat tops with 4 valve reliefs if that helps.

Twilightoptics · Posted: Mon Mar 01, 2010 7:17 pm Post subject:

Think mine are about 8-9cc.

I use a .015 shim with the pistons .025 in the hole and 66cc heads 4.1" bore gasket, .033 over gets me about 9.6:1.