The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   The 1967 - 1972 Chevrolet & GMC Pickups Message Board (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=3)
-   -   Building a Vortec 350, am I doing it right? (https://67-72chevytrucks.com/vboard/showthread.php?t=801798)

chiggins 02-25-2020 03:13 PM

Building a Vortec 350, am I doing it right?
 
To start off, I am very much a novice at engine building, and this will be my first real build. I'm just trying to do the research and get some input, so I know I'm picking the right combo of parts that will get me what I want. I'm looking for any feedback from guys that have some real experience with this and appreciate any sort of response.

I recently picked up a '98 L31 block for cheap complete with the Vortec heads (062 I believe) and roller cam. I'm wanting to build a little torque monster out of it to replace the tired old 307 in my '68. I've been doing my research and slowly compiling a parts list for it. My plan is to build a healthy, reliable, and powerful little motor for my money, with lots of lower end torque. Here's what I have so far:
- COMP Cams CL08-412-8 Xtreme Energy Cam; I picked it out for its low-end torque and power capabilities, and was confirmed by Comp that this was the right choice
Specs:
RPM range: 1,200-5,200
Duration @050: 212/218
Lift w/ 1.5: .487/.495
LSA: 110
- COMP Cams Magnum Steel Roller Tip Rocker Arms and COMP Cams Hi-Tech double roller timing set
- ARP head and main studs
- Power Products knock-off Edelbrock dual plane intake, good for 1000-6000 rpm range
- Melling HV oil pump, thin steel head gaskets, and other assorted goodies

The goal is to have about a 9.5:1 compression using the thin gaskets. To accommodate for the higher lift, I will be getting Alex's Parts' beehive spring kit that allegedly allows for .500+ lift without modification to the heads.
link: https://www.alexsparts.com/new-vorte...-130-lbs-seat/
Alongside the springs I will install screw-in head studs to allow the higher spring seat pressure.

Fuel delivery will be from either an Edelbrock 600 or 650; I have both available plus tuning kits to find the best fit. The engine will be backed by an NV3500 5 spd, and I intend on running headers with an H-pipe and single boom tube for exhaust. I plan to run perhaps a 3.73 locker in the rear some time down the road. Wheels are about 26" in height.

I've already gone through and cleaned up the block myself. Oil passages are smoothed out as well as any other ridges in the block casting. I just need to send it to the machine shop and have them do my cam bearings, honing, and final block cleaning. I intend on doing the rest of the building myself.

My power goal is to have 350+ HP and 380+ torque. I feel this is attainable based on what I've red for similar builds. Is this a good level to expect or is it wishful thinking?

Again, I appreciate any sort of feedback, either telling me what I need to fix or that I actually am gaining an ounce of an idea on what I'm talking about lol. I'd love to hear about similar builds and what you guys did to make good power.

Cheers!

SIXTY9 02-26-2020 07:38 AM

Re: Building a Vortec 350, am I doing it right?
 
Just a thought, every Small Block I have built if I used the studs it was line bored. Might want to check with your machine shop.

toolboxchev 02-26-2020 01:42 PM

Re: Building a Vortec 350, am I doing it right?
 
Everyone puts in a Melling pump. They make some new stuff now, changes in the way the pump works.

HV pumps are somewhat of a misnomer. They make 4 styles, The Chevrolet oiling system works on a bypass on the filter which most do not look at either.

Offerings from Melling:

High Volume, High Pressure
High Volume, Low Pressure
Low Volume, High Pressure
Low Volume, Low Pressure

Which ever your choice, depending on the type of driving expected, I would invest a tad bit of time in the oiling system operation.

chiggins 02-26-2020 02:06 PM

Re: Building a Vortec 350, am I doing it right?
 
I believe the one I was looking at was high volume, high pressure. The truck is barely even a weekend cruiser. Mostly just hop in it to make my quick trip to town more exciting. But once this motor is in it may be driven more regularly. Do you have a recommendation for what direction I should go with the pump?

truckster 02-26-2020 03:07 PM

Re: Building a Vortec 350, am I doing it right?
 
I would post this in the Engine and Drivetrain section; you'll get more responses.

You should easily reach those power numbers.

kaycee 02-26-2020 04:59 PM

Re: Building a Vortec 350, am I doing it right?
 
I would run full roller rockers with the roller cam

chiggins 02-26-2020 05:06 PM

Re: Building a Vortec 350, am I doing it right?
 
I would like to, but that's asking an extra $200+ over what I'm already planning to spend on the roller tips. I figured roller tips were still better than stock while still keeping this thing within budget.

GASoline71 02-26-2020 08:21 PM

Re: Building a Vortec 350, am I doing it right?
 
I have the roller tips in my 350 and they are basically like a stock rocker that makes more noise. One day I plan on replacing them.

A high pressure/high volume oil pump will have all your oil up in the top end. Unless you're drag racing, a standard volume, standard pressure pump will be just fine.

Gary

hugger6933 02-26-2020 10:25 PM

Re: Building a Vortec 350, am I doing it right?
 
I have a
Vortec headed small block sitting in one of my shop's corners. It is a flat top 355 with a small cam it ended up very close to 400 hp. I did run an air gap intake. I ran/runs really good. You will be happy with your plan and your goals are reachable. Jim

chiggins 02-27-2020 01:14 AM

Re: Building a Vortec 350, am I doing it right?
 
I did do some more reading, and running HV HP does seem to be only useful for high performance engines with tight clearances. I'm planning to run pretty standard .0020-.0025 clearances and only rev to about 6k, so yeah a standard pump does seem to be proper.

As far as the roller tips, are they not useful for any kind of power or longevity? Is it even worth running the COMP roller tip lifters or should I save the money and keep stock ones? Or would the extra splurge be worth it on full rollers?

3767 02-27-2020 09:26 AM

Re: Building a Vortec 350, am I doing it right?
 
Since u have a roller block the roller cam u picked will do just fine for the intended needs u have. The roller tip rockers are not as good as full rollers but it’s about staying/being n a budget. If u can save up for the full roller u will b happier n the end. U don’t need studs n the bottom end. Standard head and main bolts will b fine. Studs are needed in racing applications. Plenty of guys using bolts on the drag strip and there motors hold up so u will b fine as well. If u go studs, u will have to have the block line bored.look not decking the block. This will give a true flat surface and raise your compression. Surface the bottom of the heads just to give a flat and true sealing surface once u install it. Since u are going with screw n studs for the heads, go 7/16. This is a lot better than the standard 3/8 with minimum cost difference.your compression is right for the street and cam. All u need for an oil pump is standard volume and optional high pressure. With a high pressure pump, u will c close to 60 psi at idle. This style of pump was used on a 70 Camaro and it’s been around along time. Again this is an option but not a necessity. Invest in .080 push rods over the standard .060. Ditch the China intake and get either an edelbrock rpm or Holley manifold. U won’t need the air gap. Either 1 used will do better than the pro product 1. Just some food for thought. Good luck n your build, let everyone know how it all turns out.

chiggins 02-27-2020 10:33 AM

Re: Building a Vortec 350, am I doing it right?
 
Hey Vale is just a 15 minute drive from home for me!

So I'll probably ditch the main studs and put that cash towards roller rockers. I believe I did pick out 7/16 studs, there was a reasonably priced set by COMP on Summit. As for machine work, do you know of any shops in the area that aren't gonna charge an arm and a leg for decking and such? I've talked with Flowers NAPA over in Hickory but haven't quoted decking.

3767 02-27-2020 11:10 AM

Re: Building a Vortec 350, am I doing it right?
 
Mace machine shop n Morganton. Small shop, good 2 work with. Does more than flowers and cheaper. He can do all your machine work. He can also help u with any questions u may have. He has done this work for along time. His number is 828/437/8829. Addy....2838 mill race rd . U didn’t mention it but u need to get bottom end balanced. It’s worth the money. Also....check n2 new rods vs getting the old ones fixed. By the time u fix the old ones with the time/labor involved it could b cheaper to buy new ones. Look at eagle or scat. Roughly $250 a set and they are matched from the factory. This will save some time (money) vs Fixing the old ones. For now let him price all the work u need done. This will give u an idea of what u are getting for your money and time involved. If u are going to start on this u need to get it n gear. Racing season is coming and these guys will b busy getting there engines ready for the upcoming season.

randy500 02-27-2020 04:09 PM

Re: Building a Vortec 350, am I doing it right?
 
I have a build thread on a new vortec engine. I bought the cheap knock off intake and an edelbrock, the edelbrock has much larger ports below the carb. I believe its worth the extra money.
Pic of the openings in my vortec thread.
http://67-72chevytrucks.com/vboard/s...d.php?t=798068

I would stay away from the comp extreme stuff, just causes rumpy idle and carb problems, no real power gains....use something with a 112 lobe centerline. Howards cams has them, search Howards cam by part number on ebay and a guy is selling them for about $258 or so.


All times are GMT -4. The time now is 06:26 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com