Cam not compatible with overdrive? - Page 3 - 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
  #31 (permalink)  
Old 08-05-2010, 06:20 PM
1983 Z28
 
Last photo:
Join Date: Apr 2010
Location: Lima, Ohio
Posts: 80
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Well right now I'm leaning towards the XE274H. Seems to be the most aggressive cam I can run. Comp calls for a 2200+ stall converter, and says the operating range starts at 1800 RPM.

Thoughts?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #32 (permalink)  
Old 08-05-2010, 06:37 PM
hemi joe's Avatar
loves ex cop cars
 
Last photo:
Join Date: Apr 2009
Location: west deptford nj
Age: 52
Posts: 366
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
this post has totally blown my mind on overdrive.i have a 700R4 in my caprice.if you don't put car in overdrive,how do you have a problem what cam is installed.please don't beat me up but i don't understand,i thought a 700R4 was great for a big cam????????????i do understand about torque converter,but the rest makes no sence.
Reply With Quote Quick reply to this message
  #33 (permalink)  
Old 08-06-2010, 06:26 AM
Overdriv's Avatar
Member
 
Last photo:
Join Date: May 2005
Location: IL
Age: 64
Posts: 740
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by hemi joe
this post has totally blown my mind on overdrive.i have a 700R4 in my caprice.if you don't put car in overdrive,how do you have a problem what cam is installed.please don't beat me up but i don't understand,i thought a 700R4 was great for a big cam????????????i do understand about torque converter,but the rest makes no sence.
I think the point is, why overdrive if you don't plan for it and use it. If you aren't going to use OD, there are probably better choices for a trans, like the THM400. Just my opinion of course.
Reply With Quote Quick reply to this message
  #34 (permalink)  
Old 08-06-2010, 06:51 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by hemi joe
this post has totally blown my mind on overdrive.i have a 700R4 in my caprice.if you don't put car in overdrive,how do you have a problem what cam is installed.please don't beat me up but i don't understand,i thought a 700R4 was great for a big cam????????????i do understand about torque converter,but the rest makes no sence.
It just goes to show, that there's no "free lunch".

HJ, because of the relatively big drop in RPM that OD gives, this brings the engine down in RPM so low, that the engine doesn't make enough horsepower/torque (with a 'big' cam) to allow the vehicle to smoothly drive down the highway.

So, there's a limit on things. Big cam = more rear gear. But then first gear (w/its 3.06:1 ratio) becomes a ~14:1 ratio joke when using the necessary 4.56:1 rear gear that's needed to get the OD RPM up to a place where the engine's making some real power.

Obviously, if OD isn't used, and the trans is used like a 3-speed AT, well, there's not so much of a 'problem', other than the added expense of the OD trans that isn't utilized, and the cost to bullet-proof it to begin with. But in that case, I agree w/Overdriv that there are better trannys to start w/from the beginning.
Reply With Quote Quick reply to this message
  #35 (permalink)  
Old 08-06-2010, 03:36 PM
1983 Z28
 
Last photo:
Join Date: Apr 2010
Location: Lima, Ohio
Posts: 80
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Okay guys, I've done A LOT of research on the XE274H and found numerous people running it with Vortec heads and overdrive. From my research, I've gathered that around 230 duration @.050 is where you start sacrificing driveability.

The XE274 has 230/236 duration @.050. The .490 lift should work out nicely with my valve train.

Apparently, Vortec heads seem to thrive on this cam, making 400+ hp at the crank.

Car Craft built a stock Vortec 350 with some head work and an XE274 cam and made 442hp and 452 ft/lbs of torque.

With the operating range coming it at 1800 RPM's, I haven't been able to find one person having trouble with this cam and overdrive, no matter the gearing.

I also decided I'm going to get a Summit Racing 2600 stall converter. I figure it will be a good balance for street and strip.

Speak now or forever hold your peace!
Reply With Quote Quick reply to this message
  #36 (permalink)  
Old 08-06-2010, 03:41 PM
Registered User
 
Last photo:
Join Date: May 2008
Location: ohio
Posts: 1,451
Wiki Edits: 0

Thanks: 30
Thanked 42 Times in 39 Posts
Well if it was my build with that setup I would go with the comp cam xe 256 h or at the very least the next one up at the most. I have the same rear end ratio as you do but I don't have overdrive like your 700r4 and I only have a 222/230 @ 50 cam and mine is barley acceptable going down the highway with a 2200 stall for my experience as to why I am putting in a smaller cam to give me better bottom end and midrange with out taking too much off the top.

I bet once I am done will have a nice night and day difference with street manners and performance and I will be much happier with how it will run. Bottom line it's up to you on what you want. That cam is still a little on the bigger side for street ability wise with good manners. My cam does not pick up till about 2500 rpm and it does not like it in town when the rpms are below 2000 most of the time. 1800 rpm is bare minimum and its best to be a little above the rpm band for bettor results.

My smaller cam will start to go at 1500 rpm and I am always above that going through town and mine will even work with a stock stall converter and with my 2200 rpm stall I should really wake up my bottom end some. Have fun I am sure you will get something worked out. At least your asking and taking advice to heart. Some just roll with it and don't care how it runs.
Eric
Reply With Quote Quick reply to this message
  #37 (permalink)  
Old 08-06-2010, 03:42 PM
techinspector1's Avatar
Senior Curmudgeon
 
Last wiki edit: DynoSim combinations Last photo:
Join Date: Oct 2005
Location: Hemet, California, USA
Age: 72
Posts: 12,938
Wiki Edits: 326

Thanks: 759
Thanked 1,008 Times in 847 Posts
Do what you want to Junior, you're going to anyway.
Reply With Quote Quick reply to this message
  #38 (permalink)  
Old 08-06-2010, 03:49 PM
1983 Z28
 
Last photo:
Join Date: Apr 2010
Location: Lima, Ohio
Posts: 80
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by eric32
Well if it was my build with that setup I would go with the comp cam xe 256 h or at the very least the next one up at the most. I have the same rear end ratio as you do but I don't have overdrive like your 700r4 and I only have a 222/230 @ 50 cam and mine is barley acceptable going down the highway with a 2200 stall for my experience as to why I am putting in a smaller cam to give me better bottom end and midrange with out taking too much off the top.

I bet once I am done will have a nice night and day difference with street manners and performance and I will be much happier with how it will run. Bottom line it's up to you on what you want. That cam is still a little on the bigger side for street ability wise with good manners. My cam does not pick up till about 2500 rpm and it does not like it in town when the rpms are below 2000 most of the time. 1800 rpm is bare minimum and its best to be a little above the rpm band for bettor results.

My smaller cam will start to go at 1500 rpm and I am always above that going through town and mine will even work with a stock stall converter and with my 2200 rpm stall I should really wake up my bottom end some. Have fun I am sure you will get something worked out. At least your asking and taking advice to heart. Some just roll with it and don't care how it runs.
Eric
I know I'm stubborn, and to be honest I'm usually the one giving technical advice, but while I understand the different aspects of a camshaft's profile, I'm far from being an expert, which is why I'm here.

I'd rather be oversized than undersized a little with the cam, and from what I've seen the XE274 is designed exactly for my purpose. I haven't seen one person say they wished they went with a smaller cam after having the XE274.

I really don't care what the cam does below 1800 RPM. Like I said I don't need to be in OD cruising around town. As long as I can drive it around town in 3rd gear and cruise at 65-75 MPH with OD and the TCC locked, I'm a happy camper.
Reply With Quote Quick reply to this message
  #39 (permalink)  
Old 08-06-2010, 03:53 PM
Member
 
Last photo:
Join Date: Aug 2010
Location: Missouri
Posts: 466
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I would either change you cam choice or your gearing. The XE262 seems to do rather well for a Vortec combo. A roller would be better of course.
Reply With Quote Quick reply to this message
  #40 (permalink)  
Old 08-06-2010, 03:53 PM
1983 Z28
 
Last photo:
Join Date: Apr 2010
Location: Lima, Ohio
Posts: 80
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by techinspector1
Do what you want to Junior, you're going to anyway.
No, that's not accurate.

For me to not use a combination just because someone tells me not to without telling me why, that would be pretty ignorant of me.

I need to hear why this combination won't work. So far it seems to be a well matched combo. Comp says it's a great fit, it's been proven to work well with overdrive transmissions, it's been used in conjunction with Vortec heads and 350's numerous times and makes an awesome power band.

Comp recommends a minimum of a 2200 stall converter. I will be using a 2600 stall converter. I'd rather it be a little tight than too loose for my daily driver.

What's wrong with this combination?
Reply With Quote Quick reply to this message
  #41 (permalink)  
Old 08-06-2010, 03:55 PM
1983 Z28
 
Last photo:
Join Date: Apr 2010
Location: Lima, Ohio
Posts: 80
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
By the way guys, gearing really isn't my biggest concern, I don't want that to limit my cam choice.

If I put the car together and the car is a dog or can't cruise in OD, I'll do a gear swap.

I have a Ford 8.8" from a 1998 Explorer with LSD, 3.73 gears, and disc brakes I've been contemplating installing. The offset pumpkin makes it difficult without modifying the axle tubes and shafts though.
Reply With Quote Quick reply to this message
  #42 (permalink)  
Old 08-06-2010, 03:58 PM
Registered User
 
Last photo:
Join Date: May 2008
Location: ohio
Posts: 1,451
Wiki Edits: 0

Thanks: 30
Thanked 42 Times in 39 Posts
Well I had a 700r4 in my truck before I took it and the vortec motor out and put a 350 turbo in its place but anyways the overdrive never kicked on till I was out on the highway. Most overdrive's from what I have seen don't come on till around 35-40 mph anyways so if you put it into normal drive should not be any issue cruising around town.

It's just you might have surging issues or you might not. Other factors there. Since you seem you are going to go that route hope things work out for you good. As far as going too small of a cam that would be putting a stock type cam or a rv type of cam

Even mine is a lot more then that type of cam. Well good luck bud hope it all works out and you don't have any issues. Please make sure you break your cam in with all precautions you can think of. Would hate to see you ruing your motor. I bet your camaro is fun to drive though.
Take care
Eric

Last edited by eric32; 08-06-2010 at 04:07 PM.
Reply With Quote Quick reply to this message
  #43 (permalink)  
Old 08-06-2010, 04:04 PM
Member
 
Last photo:
Join Date: Aug 2010
Location: Missouri
Posts: 466
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Why not step down on the cam? What are you trying to accomplish by using a larger cam? On a street vehicle you'll be running slower from stop light to stop light and burning more fuel to do it. There are a LOT of Vortec builds with XE or Voodoo 262 or 268 cams- I would take a look at those.

I don't like running aggressive hydraulics like those series (What's the plural of series?) but if you want to run them then I would go with a 262 or 268. If you want a rougher idle have it ground on a 106 LSA; just be sure to have good headers and exhaust if you do that.
Reply With Quote Quick reply to this message
  #44 (permalink)  
Old 08-07-2010, 05:47 AM
Overdriv's Avatar
Member
 
Last photo:
Join Date: May 2005
Location: IL
Age: 64
Posts: 740
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
I just drove my pro street S10 150 miles round trip yesterday, so I tried running at different speeds to see what would happen. I have a XE274 cam, 406 SBC, 700R4, 4.56 gear. Keep in mind the XE274 will seem a bit bigger to a 350 than the 406.

At 1500 RPM in OD TCC locked, it would buck and surge on the cam. 1800 was the slowest I could go and be right on the edge of the cam. 2000 RPM it was smooth at just under 55. I usually cruise about 2100 RPM just shy of 60 MPH in OD locked. It will do that all day and get 15-16.5 MPG with or without the AC.

When I slow down to go through a town, I shift to 3rd. This also unlocks the TCC. Around town, I never run in OD, always in 3rd. My truck will shift into OD/locked at 35MPH, and it ain't pretty, buck and jump time, you get to listen to the slack in your drive line and suspension.

I can't imagine running it with a 3.42 gear. 4.11 would be border line.

Get and use one of the many speed/RPM calculators and do your own what ifs. Be realistic with your estimations.

I'm trying to give you some real experience with a combination very similar to what you are proposing. I still think you can keep the cam selection you want, enjoy the big cam sound, but in my opinion, you need to re-gear for it.
Reply With Quote Quick reply to this message
  #45 (permalink)  
Old 08-07-2010, 08:57 AM
Custom10's Avatar
my KARMA ran over my DOGMA
 

Last journal entry: SS
Last photo:
Join Date: May 2009
Location: Saskatchewan, Canada
Age: 49
Posts: 1,096
Wiki Edits: 0

Thanks: 15
Thanked 26 Times in 23 Posts
Quote:
Originally Posted by Jr. Mechanic
Well right now I'm leaning towards the XE274H. Seems to be the most aggressive cam I can run. Comp calls for a 2200+ stall converter, and says the operating range starts at 1800 RPM.

Thoughts?
Just pipping in on operating range listings that the cam companies are using here, how accurate are they really? It could be that too many folks get caught when they look at the these numbers cause they are not considering the rest of there combination. Consider my lunati 301A8LUN http://webcache.googleusercontent.co...&ct=clnk&gl=us

Let me assure you that with my vortec headed 383, 700R4, 3.73 C10 it makes for a good combination for me, its listed operating range is 1000-5800, however as an example even at 1700 rpm in overdrive its is not happy and the engine is a lug, drop in to 3rd and different story or cruise up to 2500 in OD and hang on. Just pointing this out (as others have) because you have the 700R4 and plan on some highway cruising, don't put too much into the posted operating range when making a choice. IMHO you need to stick with a smaller cam than the 274 (not too mention the probable valve train racket), but again its the cake and eat it deal, better at WOT or a good driver. As I mentioned I had bought the blue racer 214/224 from skip and was going to use it on my build, some days I wish I had but since I only run through maybe a tank of gas on the weekends during the summer, bigger is OK to a point. And if you want to talk about cold start problems?, better get a block heater, yes most our rides up here have a plug in sticking out of the grill
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 button length/clearance..? mrdreex Engine 1 04-12-2008 10:17 PM
Cam Selection and Dynamic CR Arcuden Engine 10 03-23-2008 11:03 AM
I need cam help 355s10 Engine 7 03-16-2008 05:34 PM
Help Me Pick A Cam Canadian Charlie Engine 2 11-16-2005 01:11 PM
another cam ouestion...ie...cam timing VETTE GUY Engine 0 06-28-2003 11:29 AM


All times are GMT -6. The time now is 12:28 PM.


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.