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Cheap-a$$ long rod + stroker + high CR pistons?
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morghen  



Joined: 21 Jan 2005
Posts: 8201
Location: Romania

PostPosted: Wed Jan 30, 2013 10:53 pm    Post subject: Reply with quote

looks great, but i think you could have went for 12:1
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ideola  



Joined: 01 Oct 2004
Posts: 15506
Location: Woodstock IL

PostPosted: Thu Jan 31, 2013 12:32 pm    Post subject: Reply with quote

morghen wrote:
looks great, but i think you could have went for 12:1
There weren't any off-the-shelf pistons that would get me there, plus it's a little too close to the edge for my preference. According to materials I've read, the D-Prod racers were running anywhere from 11.5:1 to 13:1, but at the expense of rebuilds every 8 hours of run time. Sure, I could do custom pistons, but the point of this exercise is to use all off-the-shelf components to see what can be done.

I am planning some pretty aggressive ignition advance once I get the EDIS installed. I can get to 11.5:1 with a .027" Cometic gasket, so I think the motor should be quite...healthy

Here's tonight's progress...

Head studs:


Head and water pump installed:

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924-76  



Joined: 05 Jun 2006
Posts: 1413
Location: Ontario, Canada

PostPosted: Thu Jan 31, 2013 8:20 pm    Post subject: Reply with quote

ideola wrote:
Head studs:

What torque specs are you using on those studs?
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ideola  



Joined: 01 Oct 2004
Posts: 15506
Location: Woodstock IL

PostPosted: Thu Jan 31, 2013 10:20 pm    Post subject: Reply with quote

924-76 wrote:
What torque specs are you using on those studs?

I'm using the instruction sheet that came in the package, which says to use the ARP assembly lube, and then torque to 90 ft lb in three successive stages, following the factory tightening sequence. I started at 45 ft lb, then did 70 the second time around, and finished up at 90.
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morghen  



Joined: 21 Jan 2005
Posts: 8201
Location: Romania

PostPosted: Thu Jan 31, 2013 11:14 pm    Post subject: Reply with quote

8 hours? did they have the distributor backwards?

Will you dry sump it? please do.
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ideola  



Joined: 01 Oct 2004
Posts: 15506
Location: Woodstock IL

PostPosted: Fri Feb 01, 2013 1:57 am    Post subject: Reply with quote

morghen wrote:
8 hours? did they have the distributor backwards?
No, but I'm sure they were running aggressive advance, and running constantly between 5500-7000 RPM (by some accounts, even higher!). So those motors at 13:1 were really stressed. Required a rebuild after each race weekend.

morghen wrote:
Will you dry sump it? please do.
Not this one. It's going to be a street car, so very hard to justify the expense. I am putting an Accusump in the Club Sport though, and still have the dry sump for the UWB motor
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ideola  



Joined: 01 Oct 2004
Posts: 15506
Location: Woodstock IL

PostPosted: Thu Mar 28, 2013 5:24 am    Post subject: Reply with quote

Long block is now completed.





High-amp [URL="http://garage.ideola.com/prod-ElectricsUpgrades.html#QualityPower"]direct fit replacement alternator[/URL]:


[URL="http://garage.ideola.com/prod-ExhaustUpgrades.html#931ENKhttp://garage.ideola.com/prod-ExhaustUpgrades.html#931ENK"]Locking Stage8 Exhaust Hardware[/URL] and [URL="http://garage.ideola.com/prod-ExhaustUpgrades.html#Headers"]MSDS Header[/URL]:


Vibratechnics "Fast Street" replacement motor mounts:


[URL="http://garage.ideola.com/prod-EFISolutions.html#36-1TW"]Ideola's 36-1 Trigger Wheel[/URL] for EFI and Programmable Ignition conversions:


[URL="http://garage.ideola.com/prod-EngineMods.html#weber"]Redline-Weber 45DCOE Carb Conversion[/URL]:





[URL="http://garage.ideola.com/prod-EFISolutions.html#DBOP"]Ideola's Distributor Block-off Plate[/URL] and Coil Pack Mount for Programmable Ignition conversions:


Natural Aluminum powder coat and high-temp black ceramic exhaust coatings:

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GeorgeV  



Joined: 14 Mar 2010
Posts: 304
Location: Brisbane, Australia

PostPosted: Thu Mar 28, 2013 6:36 pm    Post subject: Reply with quote

That engine looks great!
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Carrera RSR  



Joined: 08 Jan 2010
Posts: 2008
Location: Somerset, UK

PostPosted: Thu Mar 28, 2013 6:56 pm    Post subject: Reply with quote

Dan, you seem to have the same OCD issues I have!

Looks fantastic and I'm sure it'll sound great at full chat. Whats your anticipated red line, 7000?
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Rasta Monsta  



Joined: 12 Jul 2006
Posts: 11383
Location: PacNW

PostPosted: Fri Mar 29, 2013 12:53 am    Post subject: Reply with quote

I like that coil mount, nice piece.
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ideola  



Joined: 01 Oct 2004
Posts: 15506
Location: Woodstock IL

PostPosted: Fri Mar 29, 2013 9:59 am    Post subject: Reply with quote

Carrera RSR wrote:
Dan, you seem to have the same OCD issues I have!

Looks fantastic and I'm sure it'll sound great at full chat. Whats your anticipated red line, 7000?


LOL, too funny...I am still a bit miffed that one out of my four transmission plugs was gold while the other three are silver! No way to know what you're going to get when you order from the wholesaler, so I've resisted the urge to order more to get them to match

I don't plan to spend much time beyond 6500 RPM, but this setup should have no trouble going to 7000, given the big valve head, Stage1 cam, heavy duty springs, and the lightweight Sten Parner solid lifters. I can't wait until May, which is how long it's going to take before I can drop this thing in and even come close to firing it up!!!
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Carrera RSR  



Joined: 08 Jan 2010
Posts: 2008
Location: Somerset, UK

PostPosted: Fri Mar 29, 2013 5:24 pm    Post subject: Reply with quote

When you do fire it up Dan, we expect a video with quality audio. I'll then run it through my sound system for full effect!!
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vatoisimo  



Joined: 31 Aug 2008
Posts: 134
Location: Kent, Wa

PostPosted: Tue Apr 16, 2013 11:20 am    Post subject: Reply with quote

ideola wrote:
the_mad_electrician wrote:
What pistons would the N/A use?

Not sure what you're asking...this will be a normally aspirated build...I'm just using the 931 head because of the superior port design and flow, plus the better quench arrangement.

If you wanted to use an NA head with these rods, there are several different alternative piston choices resulting in various distances "down the hole", I'd have to go back and look at my notes to figure out which would be best. It also depends somewhat on what CR one wanted to achieve...


looks like i might have to pull my "good" motor apart because of low compression in 2-3-4 holes. Do you think that I could drop in high compression jugs without upgrading the rods?
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ideola  



Joined: 01 Oct 2004
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Location: Woodstock IL

PostPosted: Wed Apr 17, 2013 12:07 am    Post subject: Reply with quote

vatoisimo wrote:
looks like i might have to pull my "good" motor apart because of low compression in 2-3-4 holes. Do you think that I could drop in high compression jugs without upgrading the rods?


Yes, you can do this, but there are no "off-the-shelf" options for aftermarket cars as in the build documented in this thread. But if your cylinder bores are within spec (i.e. 86.5mm and not out of round), the cheapest route to achieve this would be to acquire some used 931 pistons. Depending on your deck height, with an NA head, 931 S1 slugs will yield somewhere in the vicinity of 9.7:1 (or greater) CR. 931 S2 slugs with NA head will yield 10.6:1 or greater. Just be aware, this will make the motor an interference design.

The other option would be to get custom-spec Diamond pistons, which can be done in any CR with appropriate valve reliefs for normal NA or big valve setup.
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flosho  



Joined: 01 Jul 2004
Posts: 3153
Location: Eau Claire, Wisconsin

PostPosted: Sat Apr 20, 2013 3:45 am    Post subject: Reply with quote

Dan, did you ever release aftermarket off the shelf fitments for our cars?

Otherwise I will just tell you that I'm looking to do the offset crank grind, longer rods and 88mm pistons to put me at/around 9.0-9.5:1 and I'd like valve reliefs, but it is not realistic, then I'll live with the interference.
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