f-bird'88 lift rule 350-vortec - Page 2 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #16 (permalink)  
Old 06-01-2008, 09:50 AM
DENCOUCH's Avatar
Registered User
 
Last photo:
Join Date: Nov 2007
Location: Great Pacific Northwest
Age: 67
Posts: 409
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by Stroke
You need to set a goal, a realistic goal. Then, no matter what you use, or how you go about getting there, make your goal. IMO those are el cheapo cast pistons, and sure they'd work, but what is it you are going to do with this engine? You could throw them in and add some cam along with some budget priced stuff and get what you want, or, go whole hog and make it exactly what you want without worry. First thing though, you need a specific goal for this engine and need to know where it is going to spend it's life, happily.
Exactly what you wrote. Firstly, I am a technical guy by trade, Industrial Electrican and HVAC. I am no stranger to wrenching on machinery like motorcycles 2 & 4 stroke. I have experience in setting up Harley motors & transmissions. I like to wrench stuff. My father owned a VW motor rebuilding shop that built motors both for sale to the public & for machine shops. I worked there at times for extra money. I am within spitting distance of retirement, so money is of concern.

I have modified 2 auto engines, and been disappointed in both.

I would like a truck built around a 350 sbc. When I step on the gas, I would like it to go as fast or faster than traffic. mileage is not an issue with me. I am willing to give up some bottom end torque for some scoot. My plans are to address the rear end with 3.73 or 4.11 gears, coupled to a stall converter with around a 2600-3000 stall to work with the cam that was recommended.

All of my motors in the past have been built around 79cc heads, and I have learned the low compression is one heck of a hurdle in the pursuit of decent HP.

What I am learning now is the importance of proper quench and thee role it plays in compression, detonation and proper spark curve. I am learning this stuff and some here are helping me a great deal.

Some are forthcoming with the help, and others have to have the information dragged out of them with an engine hoist. I like the attitude of F-bird'88. Tech-inspector is another wise one, but sometimes he comes across as a bit condescending.

If indexing the block and heads is a requirement (born of experience and knowledge of others) for a proper motor set up, then this I will have to do. I have in the past always asked for a rebore when fitting new pistons. From what I know, pistons were always bored undersized then honed for each piston clearance. Maybe things are different now.

I need to be able to call on others to tell me if I am going cheap (bad!) or bargain with my parts selection. Some stuff is a bargain because it has been out there for a zillion years. That does not make it a cheap part.

This is my F-bird'88 suggested build:

a basic 350ci SBC short block with flat top pistons
+ 062 or 906 GM vortec heads
Isky #205D valves springs minus the inner damper
Stock OEM vortec retainers, seals locks and rocker arms
Isky #201278 camshaft 278-278 .450" .450" lift 234-234@.050" 106 LSA
Edelbrock Performer RPM Manifold and 750cfm 4bbl carb
1-5/8" headers 2.5" dual exhaust.
This combo makes more power and torque than the Edelbrock RPM cam will make without needing vortec cylinder head machining modifications to accomodate the .488"-.510" valve lift of the Edelbrock RPM camshaft.
Should use a 10" high stall torque converter and 3.73 to 4.10 rear gearing for best results. (same as the rpm cam needs)
Isky #201288 will make even more top end power all with just .450" valve lift.
Degree the cam in on a 102-103 intake C/L for best results.

All help is appreciated always.
I am not so smart as to know everything there is about this subject, and I am smart enough to know that. This is where you guys come in.

Your success is going to be shared, and I thank you for that. I really do.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #17 (permalink)  
Old 06-01-2008, 11:54 AM
NXS's Avatar
NXS NXS is offline
wind & fire = guides to power
 
Last photo:
Join Date: Nov 2004
Location: Oklahoma
Posts: 1,534
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
You don't need to machine for the performer rpm can, just use the old style o-ring type valve seals (don't use the umbrella seals!). That will get you around 525" lift with the vortec heads.
I've ran 510" roller cams on them with no machine work whatsoever spinning 6200 rpm. basically the exact same setup fbirds saying..intake and all.

they run great.

The ultimate $1000 350SBC
Reply With Quote Quick reply to this message
  #18 (permalink)  
Old 06-01-2008, 01:51 PM
King of my Man-cave.
 
Last photo:
Join Date: Nov 2003
Location: Michigan
Age: 55
Posts: 2,901
Wiki Edits: 0

Thanks: 4
Thanked 16 Times in 13 Posts
Quote:
Originally Posted by NXS
You don't need to machine for the performer rpm can, just use the old style o-ring type valve seals (don't use the umbrella seals!). That will get you around 525" lift with the vortec heads.
I've ran 510" roller cams on them with no machine work whatsoever spinning 6200 rpm. basically the exact same setup fbirds saying..intake and all.

they run great.

The ultimate $1000 350SBC
If you don't use the oil shields with the o-ring seals you will have an oil burner. Using the oil shield will set the springs up .030" tighter. You'll probably need to cut the spring pocket deeper or use a +.050" keeper. Kinda negates the easy fix of using the o-ring seal.

Plus, Vor-Tec valve don't have the o-ring groove in them.


tom
Reply With Quote Quick reply to this message
  #19 (permalink)  
Old 06-01-2008, 01:56 PM
King of my Man-cave.
 
Last photo:
Join Date: Nov 2003
Location: Michigan
Age: 55
Posts: 2,901
Wiki Edits: 0

Thanks: 4
Thanked 16 Times in 13 Posts
Quote:
Originally Posted by DENCOUCH
Ok, so what I am going to do now is:

1. have the block decked JUST enough to make sure Ihave it indexed 90 degrees to the crank.

2. have a flat surface for optimum sealing for the .015 steel shim head gasket.

3. have the heads checked for flatness and milled if needed. Perhaps .020.

4. I am considering an .30 overbore to fit a set of pistons. I have seen these and am wondering if they are ok or not. I was looking for something with less than +7.00 cc. +5 cc sounds good if I want to keep the compression up.
These Pistons from Summit.


It seems silly to me to get a .015 head gasket, mill everything & then go to a +7 cc flat top piston.

I need help with this guys, there is so much stuff to keep track of.
Those pistons are bottom of the barrel, stock, rebuilder pistons. They are heavy and are decked .020". Look for something that is hypereutectic and a little lighter that isn't decked. The H345NCP by Sealed Power (Speed-Pro) would be a better choice. Plus, you don't have to run a bigger top ring gap, which you would have to do with a Keith Black hypereutectic.

tom
Reply With Quote Quick reply to this message
  #20 (permalink)  
Old 06-01-2008, 01:58 PM
NXS's Avatar
NXS NXS is offline
wind & fire = guides to power
 
Last photo:
Join Date: Nov 2004
Location: Oklahoma
Posts: 1,534
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by machine shop tom
If you don't use the oil shields with the o-ring seals you will have an oil burner. Using the oil shield will set the springs up .030" tighter. You'll probably need to cut the spring pocket deeper or use a +.050" keeper. Kinda negates the easy fix of using the o-ring seal.

Plus, Vor-Tec valve don't have the o-ring groove in them.


tom
Ok, well the best ones to use are really the 2.2L Chrysler turbo umbrella valve seals, they fit perfect..but I can't tell you guys all the secrets...a google search for "vortec heads max lift " might help ya too.
Reply With Quote Quick reply to this message
  #21 (permalink)  
Old 06-01-2008, 02:21 PM
DENCOUCH's Avatar
Registered User
 
Last photo:
Join Date: Nov 2007
Location: Great Pacific Northwest
Age: 67
Posts: 409
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Thanks Machineshop Tom

I managed to clean things up this morning, mostly my garage. I brushed off the piston tops for the sake of photograph & to gather some dimensions. I did not find any numbers stamped into the piston crowns. I miked the bore & found ita bit under 4.00, this I attribute to a slight cylinder piston ridge. The numbers for the dish are on the pix. Under a shop light, evidence of the cylinder honing is visible.



Here are the specs as I measured them.



The last honing crosshatch is visible.
Reply With Quote Quick reply to this message
  #22 (permalink)  
Old 06-01-2008, 02:48 PM
NXS's Avatar
NXS NXS is offline
wind & fire = guides to power
 
Last photo:
Join Date: Nov 2004
Location: Oklahoma
Posts: 1,534
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
what year or casting number is the block?
Reply With Quote Quick reply to this message
  #23 (permalink)  
Old 06-01-2008, 03:25 PM
DENCOUCH's Avatar
Registered User
 
Last photo:
Join Date: Nov 2007
Location: Great Pacific Northwest
Age: 67
Posts: 409
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
It is a crate motor Hecho en Mexico.

I ran the numbers & can't find a dern thing on it.
Reply With Quote Quick reply to this message
  #24 (permalink)  
Old 06-01-2008, 03:36 PM
King of my Man-cave.
 
Last photo:
Join Date: Nov 2003
Location: Michigan
Age: 55
Posts: 2,901
Wiki Edits: 0

Thanks: 4
Thanked 16 Times in 13 Posts
Quote:
Originally Posted by NXS
Ok, well the best ones to use are really the 2.2L Chrysler turbo umbrella valve seals, they fit perfect..but I can't tell you guys all the secrets...a google search for "vortec heads max lift " might help ya too.
The Chrysler 2.2 Turbo seals are no different than the Chrysler 2.2/2.5 seals.

Plus, they are designed for a .500" OD guide with a retaining groove cut into it.

The guide must be cut to .500" OD, in which case there are better seals for the job.

tom
Reply With Quote Quick reply to this message
  #25 (permalink)  
Old 06-01-2008, 03:37 PM
King of my Man-cave.
 
Last photo:
Join Date: Nov 2003
Location: Michigan
Age: 55
Posts: 2,901
Wiki Edits: 0

Thanks: 4
Thanked 16 Times in 13 Posts
Quote:
Originally Posted by DENCOUCH
It is a crate motor Hecho en Mexico.

I ran the numbers & can't find a dern thing on it.
Those pistons are the same as the KB cast ones you spoke of earlier.

tom
Reply With Quote Quick reply to this message
  #26 (permalink)  
Old 06-01-2008, 04:26 PM
NXS's Avatar
NXS NXS is offline
wind & fire = guides to power
 
Last photo:
Join Date: Nov 2004
Location: Oklahoma
Posts: 1,534
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by machine shop tom
The Chrysler 2.2 Turbo seals are no different than the Chrysler 2.2/2.5 seals.

Plus, they are designed for a .500" OD guide with a retaining groove cut into it.

The guide must be cut to .500" OD, in which case there are better seals for the job.

tom
sounds better. so what seals work better then??? if you know some speak up.
Reply With Quote Quick reply to this message
  #27 (permalink)  
Old 06-01-2008, 04:51 PM
King of my Man-cave.
 
Last photo:
Join Date: Nov 2003
Location: Michigan
Age: 55
Posts: 2,901
Wiki Edits: 0

Thanks: 4
Thanked 16 Times in 13 Posts
Quote:
Originally Posted by NXS
sounds better. so what seals work better then??? if you know some speak up.
Enginetech S2926

Engine Pro 35-108V

Both for .500" OD guides.

tom
Reply With Quote Quick reply to this message
  #28 (permalink)  
Old 06-01-2008, 05:01 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,284
Wiki Edits: 0

Thanks: 5
Thanked 399 Times in 393 Posts
You mis understood the dimensions required.

You need to find the average of the major and minor diameters of the piston dish. because the wall of the piston dish is not 90deg square.
( blue arrows....... purple arrows)

Measure:
The diameter of the blue arrows + the diameter of the purple arrows divided by 2. (averaged dish diameter)

??? I assume you meant the pistons dish bottom is .090" from the deck with the piston is at TDC, not .900" = (a .049" deep dish)

you add 5cc for the 4 valve reliefs.

I guestimate/calculate your piston dish volume at -12 to -15cc ( I allowed 2 to 3 extra cc for the volume of the 3.64" bevel on the top of the piston. (Don;t know how deep it is.)

Based on the numbers you would need to shave the heads to 58cc to get a cr of 9.46 to 9.77 using those pistons with a .015" gasket.

Just enough for the Isky cam I recommended. (I would not go with less) You'll probabily need to shave .060" off the vortec heads assuming they are in fact 64cc out of the box.
If after ccing them you find the chamber volume is 62cc, then shave .040" off them. CC the vortec heads first. "measure twice, cut once"

A "2600 stall" is not enough converter stall. You want a 10" converter (3200 to 3600stall) EG: JEGS #555-60403 (th-350, th-400 trans)

The 4.10's is based on a 3200 to 3600lb vehicle weight and 26" to 28" tires.

A "truck" ( unless its a S-10) weights a lot more than this and usually has taller tires.
For a truck plan on a higher rear gear ratio. How much does your truck actually weight? What tire diameter will you be using?

The whole point is to use the stock GM vortec head assembly "12558060"
part number, as is without modification other than a simple quick valve spring swap and shaving them down to reduce the chamber volume in this case.
Install the new valve springs (Isky 205D or Lunati 73943) without the inner damper and use the GM OEM vortec valve seals, retainers and locks over again. They work very well.

The whole point is. Keep it simple and keep it (low) cost effective.

As long as it is in good over all condition, the bottom end of this motor is plenty strong for your purposes. If its in good shape, don't bother rebuilding it

Anybody can build a $4000 400hp street motor.
Attached Thumbnails
Click image for larger version

Name:	dish1dvv.JPG
Views:	2013
Size:	89.6 KB
ID:	30363  

Last edited by F-BIRD'88; 06-01-2008 at 05:49 PM.
Reply With Quote Quick reply to this message
  #29 (permalink)  
Old 06-01-2008, 05:37 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,284
Wiki Edits: 0

Thanks: 5
Thanked 399 Times in 393 Posts
What fuel will you be using every day?
Reply With Quote Quick reply to this message
  #30 (permalink)  
Old 06-01-2008, 06:03 PM
DENCOUCH's Avatar
Registered User
 
Last photo:
Join Date: Nov 2007
Location: Great Pacific Northwest
Age: 67
Posts: 409
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
MachineShopTom

Thanks for the link to the pistons, I am going with your suggestion. The H345NCP's look great with a Compression dist 1.560 and Deck Clearance .025 give me some numbers I can work with.

I am thinking that with a .015 steel shim head gasket my quench is going to be .040, true?

If that is the case, then I am going to have around .020 to spend in decking the block and milling the heads. With these head gaskets, I am honestly going for a flat mating surface between the components.

Thanks for the suggestion on the pistons, it is appreciated a great deal.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
ARE 305 and 350 VORTEC HEADS SAME badriand Engine 39 04-06-2011 09:40 AM
Vortec 350 gasket ? Artemis Entreri Engine 3 09-15-2007 12:56 PM
305 vortec heads vs 350 vortec rimracers Engine 6 04-02-2007 09:41 PM
96 chevy 305 vortec heads on 350 block badriand Engine 6 02-20-2006 08:45 AM
305 vortec heads on a 350 tonylsg Engine 13 09-21-2003 06:54 PM


All times are GMT -6. The time now is 07:33 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.