Need help with cam choice - 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
  #1 (permalink)  
Old 05-19-2012, 11:29 AM
Caprice Sleeper's Avatar
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Brimfield, Ma
Age: 28
Posts: 19
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Need help with cam choice

I need a little guidance when it comes to what cam to install in my engine. The car is a 1980 chevy caprice that is a daily driver. I want to make as much power as I can while keeping it a practical daily driven vehicle. The engine is a 1990 305 out of a caprice. I have a set of stock vortec heads for it (10239906) and will be most likely be running a edelbrock vortec manifold or whatever will accept a spread bore cab. Carb will be a rebuilt stock Q-jet. Stock HEI distributor. Transmission is a 200 4r with a stock lock up torque converter for a 305 (I plan on getting a higher stall converter but it will depend on what came I use, that is also something I need guidance in choosing). The 200 4r is currently installed in my car now but my car originally had a 200c so i think my rear end gears might be a little to high for use wih a overdrive tranny. I believe i have 2.76 gears now and I can use the rear end from my donor car (3.08 I think) to help keep the engine in a better rpm range on the high way. I don't know yet if the engine has dished pistons or not but it is a stock 1990 305 tbi caprice engine. Once again the car is daily driven and high way travel is often. Any help I can get will be much appreciated, Thank you. Please don't tell me to stop building my 305 and get a 350, I already have a 350 block bored .040 over that will be built someday, I just can't afford to do so at this time. Thanks again.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 05-19-2012, 11:37 AM
Caprice Sleeper's Avatar
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Brimfield, Ma
Age: 28
Posts: 19
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I forgot about exhaust. I was going to run the factory manifolds with a y-pipe and mufflerfor now. I want to run headers and dual exhaust but i'm not sure if I should go with full length or shorty. I figured that factory manifolds with a big cam would be kind of counter productive but I'm no expert. thanks everyone.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 05-19-2012, 01:40 PM
GMC boogie's Avatar
Member
 
Last photo:
Join Date: Nov 2004
Location: Louisiana
Age: 48
Posts: 613
Wiki Edits: 0

Thanks: 1
Thanked 18 Times in 18 Posts
Something along the lines of a Comp Cams 08-408-8 or the GM ramjet cam would be a good choice.

The Vortec heads on a 305 will drop the CR of your 305 and the numerically low gear set along with over drive will require a short cam.

I would stay with a cam like this even if you went to a different gear...for a big car,305,daily driver.
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 05-19-2012, 01:47 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,456
Wiki Edits: 0

Thanks: 2
Thanked 322 Times in 319 Posts
Use the stock cam you got until you can upgrade the exhaust and get some 3.73 gears. Mill .040" off your vortec heads and install on the 305 using a thin .015" shim gasket Felpro 1094.

flat tappet 204-214- .420-.442 112

Hyd roller (oem roller bock) Howards 180225 or similar
like the GM ZZ4 cam 208-221 112 .474 .510

Again keep the stock cam until you do these upgrades.
get a 245MM high stall lock up converter.
The stall you see will be about 500rpm LESS than advertized when behind a lil 305 so be generous on teh stall choice.
Most are rated for a 350 CID motor.

The 3.73's will give you strong acceleration and great crusing w a th2004r in OD
even 4.10's will work great.

3.08's are a waste of time.

Until you uncork (exhaust) and speed up (gears) the motor there is no point in recamming it now.
long tube headers and dual 2.5" exhaust will make the most power
You are putting the cart before the horse.

For best results your 305 should have the flat top pistons.
getting the compression ratio right is critical to this HO cam, vortec head , gear ratio 305 CID combo
As close to 10:1 as possible is what you are after.
(Flat top pistons .040" .050" shaved vortecs (58-59cc) , .015" shim gasket)

Last edited by F-BIRD'88; 05-19-2012 at 02:01 PM.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 05-19-2012, 01:51 PM
GMC boogie's Avatar
Member
 
Last photo:
Join Date: Nov 2004
Location: Louisiana
Age: 48
Posts: 613
Wiki Edits: 0

Thanks: 1
Thanked 18 Times in 18 Posts
Here is some info on the Ramjet cam if interested:

http://www.summitracing.com/parts/NAL-14097395/
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 05-19-2012, 02:59 PM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,652
Wiki Edits: 0

Thanks: 15
Thanked 58 Times in 55 Posts
I wouldn't mill Vortec heads, they're already thin enough as it is.
Next is to ask since your engine is a 90 model out of a passenger car it's got a roller cam installed. If your to use Vortec heads on a 305 your limited on the cam choice. I have a roller cam for sale that fits your needs perfectly.
It's a comp .206 duration @.050, ideal for your purposes and it'll work with the lower compression due to the larger chambers of the vortec heads. I would use a thinner head gasket. I would use the GM .028 thickness head gaskets. Get a set of long tube headers. As for gears I would use 3.42's. If your running stock tire sizes they would be ideal with OD. however if you planning on running wheels that are 18 inches or more taller then you'll want a lower gear according to the wheel and tire size. If your interested in the cam I have shoot me a PM, it has less than 3000 miles on it and you'll get it far cheaper than you'll get it anywhere else. Also with almost any cam you pick, you will need to have the valve guide clearance opened up as the limit on stock vortec heads are around .450 lift. plus you'll need valve springs to match the cam.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 05-21-2012, 09:15 AM
Caprice Sleeper's Avatar
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Brimfield, Ma
Age: 28
Posts: 19
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Thanks everyone for the info, the help is much appreciated. I did some checking and I found out I do have a roller block. There is also a hole behind the fuel pump block off plate, I can see what looks to be an eccentric on the cam to run the pump but I not sure yet. I think I will just keep my factory came for now due to the cost of a roller cam and lifter kit and the fact that my heads will need maching to accept a bigger cam. Slapping the vortec 906's on a 305 will give me a liitle more power than stock, alot more than the 229 V6 i have now. Thans again for the help.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 05-21-2012, 10:36 AM
DoubleVision's Avatar
Not Considered a Senior Member
 
Last photo:
Join Date: Oct 2002
Location: Heart Of Dixie
Age: 40
Posts: 10,652
Wiki Edits: 0

Thanks: 15
Thanked 58 Times in 55 Posts
If it already has a roller cam you don't need to buy lifters. You reuse the lifters it has in it. If it doesn't have a roller cam but a roller block, then you can get a set of roller lifters from the junkyard, along with the dog bones, spider and cam retainer plate for next to nothing.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 05-21-2012, 11:01 AM
Caprice Sleeper's Avatar
Registered User
 
Last photo:
Join Date: Apr 2010
Location: Brimfield, Ma
Age: 28
Posts: 19
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I have a roller cam not just a roller block. I should of specified that, my mistake. I didn't know roller lifters can be reused when installing a new cam, good to know. Thanks DoubleVision.
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:
If you do not want to register, fill this field only and the name will be used as user name for your post.
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
cam choice 91s10 Engine 7 10-20-2011 05:53 PM
Help with cam Choice ???? BG383 Engine 6 03-02-2011 07:07 PM
Cam choice onthethreshold Hotrodding Basics 13 02-05-2011 05:15 PM
cam choice??? markzepp820 Engine 9 03-04-2010 05:05 AM
Cam choice Schoust Engine 0 02-04-2004 11:30 AM


All times are GMT -6. The time now is 01:19 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.