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Discussion Starter #1 (Edited)
Well, here we go - it's another 987 LS3 conversion. I blew the engine on the track a few months back, just before moving overseas (Norway). So a perfect time for the car to be up on a lift for a heart transplant. I'm disappointed I won't be there to do... err... attempt the job myself. However, I've got a good shop in Houston to help me out - so they'll be tackling this one. All the big parts are in, so the project has begun.

Here's the main parts/selections we've decided on:

  • Renegade Conversion Kit, w/upgraded clutch
  • Starting with a LS3 / 525hp crate motor from GM PP
  • Corvette oil pan, with windage/scraper tray & accusump
  • Cayman S transmission + cooler + Guard LSD
  • Astra H (MK4/5) power steering pump (rumored to be same TRW pump as Porsche Motorsports... and $80)
Many thanks to all the help from Fingers, Joshuaj, and others for answering my questions to help get this off the ground.

10.jpg 6.jpg
The Culprit above...

The_Space.jpg LS3-Out-of-the-box.jpg
The work space, and the replacement.
 

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Looking forward to seeing it all come together. Best of luck to you. What do you do about the computer? Would love to cruise with this car when she's all buttoned up!

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

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Discussion Starter #4
Intake reversed, clutch on...

Engine_Assembly.jpg
 

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Discussion Starter #6
I'll try to get the part number soon. I corrected my original post as well... maybe I shouldn't type it from memory next time! It's from an Astra H, Mk4 (or Mk5). There's two models, one is from TRW - and it's this TRW one that is claimed on some forums to be the same. ~$80 is used, off ebay UK, shipped to the US.

Here's the link for the one I bought: MK5 VAUXHALL ASTRA H ELECTRIC POWER STEERING PUMP / 2004 - 2010 | eBay

This is a trial at this point, but will keep the thread updated if it works or not. I'm hoping to come across a true Motorsports one next time I'm home to compare as well.
 

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Conscience not included
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Wow! Well, thank goodness there is a reasonably affordable solution out there. I assume that $4k for the conversion kit + $10k for motor + labor is still far less than the cost of a replacement motor. And it'll likely be more durable.

I checked out Renegade Hybrids and the work they do is incredible. As great as Porsche motors are, they are overpriced and underpowered

EDIT: Just thought of this, but what do you do for the exhaust system? Custom job?
 

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Discussion Starter #8
Wow! Well, thank goodness there is a reasonably affordable solution out there.
We'll see how 'reasonably affordable' it is at the end. ;) Granted, I've got a lot of extras going in... but don't underestimate all the bits & pieces that add in to a project like this. For me, I'm dumping money up front, with the hope that the future it will pay off. (ex. Replacement engines at 1/4 the cost.) However if money was what drove me to the decision, I would have probably just sold the car and cut my losses. This is a car I love, and will soon truly be 'my' car.

Exhaust will be custom, you can see a good example in Finger's thread. I'm not entirely sure how extreme we're going to go yet for mine.
 

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What are your thoughts on LS3 low boost set up. I want to do an LS swap eventually (hoping for 100k miles first) and I love the idea of a low boost induction set up. The cost isn't much more if you piece it together and the LS3 handles less than 10psi on stock internals easily. Those small parts add up quick on a build like this, when I LS swapped my 68 GTO I ended up 4k over budget. Kept running into the whole "might as well get the best and not worry about it later" scenario. Love the build, best of luck to you.

Sent from my SAMSUNG-SM-G935A using Tapatalk
 

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Discussion Starter #10
What are your thoughts on LS3 low boost set up.
I think it would be a blast - but I think with that you go from reasonable conversion, to full on custom.

The guys who've already completed there's could probably speak better towards available space, and getting enough air through there to keep it cool. With >500hp already available in NA form, I'm not sure if boost is really needed. But with these projects, 'need' is a pretty useless word. :)

My worry would be the other drive line components. They seem to hold up fine on the crate LS's... but everything does have a limit.
 

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There is no space for an inter-cooler. You can get all the power you need from an NA small block. Just buy a 427 or 454 LS motor instead of spending money on turbos and coolers 600 + HP is not hard to get in an NA motor
 

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Discussion Starter #12
Not much progress... but felt the need to update anyway. They've got a dummy block in for fit-up, and should be putting in the real motor here in the next couple weeks.

Mock-up.jpg
 

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Not much progress... but felt the need to update anyway. They've got a dummy block in for fit-up, and should be putting in the real motor here in the next couple weeks.

View attachment 134809

Nice perspective! Looks like the firewall cut is very clean an symmetrical?
 

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Discussion Starter #14
Nice perspective! Looks like the firewall cut is very clean an symmetrical?
That was prior to any cuts actually. What you see is just the access panels removed. However - we now have some cuts and a test fitment of the actual engine.

05-Test-Fit2.jpg
 

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That was prior to any cuts actually. What you see is just the access panels removed. However - we now have some cuts and a test fitment of the actual engine.

View attachment 135138
Cool, so does the LS3 need about 3-4" more space into the passenger compartment as it looks near the top of this photo?
 

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Discussion Starter #16
Cool, so does the LS3 need about 3-4" more space into the passenger compartment as it looks near the top of this photo?
That sounds about right. I'm not with the car, so can't really measure. Another shot from the top:
06-Test-Fit.jpg
 

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What are your thoughts on LS3 low boost set up. I want to do an LS swap eventually (hoping for 100k miles first) and I love the idea of a low boost induction set up. The cost isn't much more if you piece it together and the LS3 handles less than 10psi on stock internals easily. Those small parts add up quick on a build like this, when I LS swapped my 68 GTO I ended up 4k over budget. Kept running into the whole "might as well get the best and not worry about it later" scenario. Love the build, best of luck to you.

Sent from my SAMSUNG-SM-G935A using Tapatalk
I think it would be a blast - but I think with that you go from reasonable conversion, to full on custom.

The guys who've already completed there's could probably speak better towards available space, and getting enough air through there to keep it cool. With >500hp already available in NA form, I'm not sure if boost is really needed. But with these projects, 'need' is a pretty useless word. :)

My worry would be the other drive line components. They seem to hold up fine on the crate LS's... but everything does have a limit.
With the LS3 you chose rated at 525 HP, do you honestly think that boost would be necessary!? What was the stock 3.4l, about 300 HP... with the LS3 all you need to do is attach small wings and she will fly! :eek:
 

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Discussion Starter #19
With the LS3 you chose rated at 525 HP, do you honestly think that boost would be necessary!? What was the stock 3.4l, about 300 HP... with the LS3 all you need to do is attach small wings and she will fly! :eek:
I don't think there's really anything necessary about putting a 500+hp V8 in to a Cayman... but that's not why I'm doing it! :burnout:

But yes - I agree... adding boost is over-the-top. Although I've done dumber things in my life... :D
 

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Discussion Starter #20
Intake on and at the fab shop... it's getting serious! Against any sane judgement - we went with the Edelbrock intake... mostly because I love how it looks.

Now it's time to finalize the intake/cooling routes and build the cage. I'll be in town to see the car next week, so hopefully will have a more in-depth update around the 1st.

Intake_in.jpg
 
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