Desktop Dyno request - 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 12-07-2006, 12:36 PM
Registered User
 
Last photo:
Join Date: Mar 2006
Location: Minnesota
Posts: 46
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Desktop Dyno request

Is it possible for anyone to run a desktop dyno on some specs that I'm having built for a motor? Is this exercise worth anything? What specs would you need?

I'm just curious, because I have the final specs picked, but it's going to several months before I can get any kind of SOTP readings. So I just want a little synthetic taste now.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 12-07-2006, 01:25 PM
firestone's Avatar
http://teamrfc.gospelcom.net
 
Last photo:
Join Date: Nov 2003
Location: Fenton MI
Age: 32
Posts: 1,743
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Give us as many specifications as you can, and we can DD it for you and/or find combos like it to compare.

Adam
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 12-07-2006, 02:38 PM
curtis73's Avatar
Hates: Liver. Loves: Diesel
 
Last wiki edit: How to find cheap parts
Last journal entry: 1999-2001: Getting it on the road
Last photo:
Join Date: Dec 2005
Location: Pittsburgh, PA
Age: 40
Posts: 5,128
Wiki Edits: 16

Thanks: 0
Thanked 2 Times in 2 Posts
We need:

What engine and overbore
head casting or part description (or flow specs would be even better)
valve sizes, if you know them
compression
carb size
intake type or description
exhaust; manifolds or headers, and if its open or with mufflers
and every cam spec you can find
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 12-07-2006, 03:09 PM
Registered User
 
Last photo:
Join Date: Mar 2006
Location: Minnesota
Posts: 46
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Pontiac 455 bored .030 over =462

bore : 4.151 + .030 = 4.181
stroke : 4.21
standard gasket : .038
zero decked
Edelbrock 72cc heads CNC ported to flow 310
Valves are 2.19 intake 1.77 exhaust
pistons are 20cc dished weisco custom
expected compression is 10.25:1
intake is port matched single plane
MPFI with 90mm throttle body
Not sure on plenum yet, but think volume will be custom at 70% of displacement or 323 CID
Cam is hydraulic roller 230-236 @ .050 112 LSA with lift 560 intake 570 exhaust (1.50 rocker)
I think exhaust will be long branch cast which is a nice flowing compromise without going to headers, but part of this exercise would be helpful to know how important the exhale is.
probable RPM limit 5,300 ish.

Comparables are coming in 520ish HP and nearly 600 #/lb torque with a torque curve you can play a game of snooker on. Although, my cam selection is a bit different from others have done, so i expect an easier idle and give some up on the top end.

thanks in advance,
scott.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 12-07-2006, 06:58 PM
curtis73's Avatar
Hates: Liver. Loves: Diesel
 
Last wiki edit: How to find cheap parts
Last journal entry: 1999-2001: Getting it on the road
Last photo:
Join Date: Dec 2005
Location: Pittsburgh, PA
Age: 40
Posts: 5,128
Wiki Edits: 16

Thanks: 0
Thanked 2 Times in 2 Posts
Here you go... That's a guess on a couple things. I had a head file that was close to your Edelbrocks so I used it. Not sure how mid-lift values compare.
This is simulated with "H.P. manifolds and mufflers". Small tube headers with mufflers was good for a solid 30 lb-ft and nearly 50 hp.
Attached Thumbnails
Click image for larger version

Name:	455poncho.jpg
Views:	114
Size:	113.4 KB
ID:	16703  
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 12-07-2006, 07:46 PM
Registered User
 
Last photo:
Join Date: Mar 2006
Location: Minnesota
Posts: 46
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
thanks curtis.

in about 6 months i'll revisit this and compare vs what i produce. short block is machined and assembled, i'm waiting for the heads & intake.

interesting comment about the headers being worth 50HP & 30tq. must be because this thing really needs to breathe.

i'll see if i can dig up the actual dyno pull from a recent comparable. i thought this torque curve would be flatter based on what i saw on the other one; especially because his cam was one step closer to the gnarly side.

thanks again.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 12-07-2006, 10:06 PM
Registered User
 
Last photo:
Join Date: Mar 2006
Location: Minnesota
Posts: 46
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
here's the data from the comparable Pontiac. same block, bore, stroke, similar heads. and actually, the cam is extremely similar (hydo. roller 230/236 @.050 with 114 LSA).

pretty cool, the DD graph above nearly sits on top of this graph. The extra RPM above made the perspective weird for a minute.



Torque HP
2500 509 242
2600 505 250
2700 507 261
2800 511 272
2900 516 285
3000 530 303
3100 539 318
3200 547 333
3300 558 351
3400 563 365
3500 575 383
3600 577 396
3700 583 411
3800 586 424
3900 585 435
4000 590 450
4100 588 459
4200 589 471
4300 582 477
4400 579 485
4500 577 494
4600 568 498
4700 562 503
4800 552 504
4900 538 502
5000 526 500
5100 520 505
5200 507 502
5300 492 497
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 10-03-2007, 08:44 PM
Registered User
 
Last photo:
Join Date: Mar 2006
Location: Minnesota
Posts: 46
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
FINALLY made it to the dyno.

527 HP / 550 TQ

used shop carbs for break-in, will sort through EFI later. first pulls from 850 CFM Holley carb, final pulls were from 1,000 CFM Holley hp series carb 80513-1

the notables from the dyno visit:

- remarkably smooth idle
- a flat torque curve
- this much HP through cast manifolds?
- even the HP curve flattens - check out 5,200 through 5,500
- he thought the Tomahawk manifold cost a lot of power vs. an RPM manifold because of the sharp turns
- valley pan did not leak - he said a lot of them do.
- a perfect example of why to break-in at the dyno - the windage tray hitting was nice to have found there - was able to pull the oil pan off while on the dyno, and have a pro notice the problem, coach me through it, and offer me a bag to breathe into.

here's the curves:

RPM TRQ HP
3400 487 316
3500 490 326
3600 494 339
3700 500 353
3800 511 370
3900 521 387
4000 533 406
4100 544 424
4200 549 439
4300 550 450
4400 550 461
4500 549 470
4600 545 478
4700 544 487
4800 547 500
4900 547 511
5000 544 517
5100 538 522
5200 530 525
5300 522 527
5400 512 527
5500 503 526
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
desktop dyno request please 66 T-Bird Engine 0 05-23-2006 05:41 PM
desktop dyno request....please nettio Engine 8 01-16-2006 04:01 PM
another desktop dyno request 82c10 Engine 6 12-16-2005 04:35 AM
Desktop Dyno Request please DHMag Engine 2 12-06-2005 01:18 AM
Please desktop dyno this 454 wo/aftermkt heads that ran a 13.1 on its 2nd 1/4 ever elukas Engine 7 01-03-2004 01:24 PM


All times are GMT -6. The time now is 09:02 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.