Got a deal on parts so an LS3 build is a go. Short block is being thrown together by SD Parts but I'm doing the top end on my own and on a budget (for the first iteration.) Going in my ~3250lb raceweight car for autocross on 335 Hoosiers, equivalent of a 3.98 rear gear that will live in 2nd gear only through a mini-twin 7.25" clutch. E85 on the Hoosiers and pump 93 for street tire events with a flex fuel tune. Aviaid dry sump to avoid starvation issues. I did not budget for this build but the old engine is losing compression and I got an offer on the new bottom end that I couldn't refuse. With that said, the engine will make more power than I can use at most events so I'm trying to reign the costs back in by keeping a budget on the top end.

New LS3 block
4" 24x Manley super lightweight crank
Manley H beams
Manley 4.068" 11.5:1 pistons

Cylinder heads: Used LS3 heads seem a bit expensive as I assume I will have to spend a few hundred at the machine shop to get them cleaned up. What's the best bang for the buck option to get this thing back out at events next season? I've seen the Speedmaster stuff but I just assume that isn't something worth pursuing. Should I just be patient on the used market? Or am I being stupid by not just buying new stock? Planning on topping it with a stock LS3 intake for now and then replacing that whenever I go through the heads for round 2.

Cam: I am a little nervous using the cheap LS7 lifters for this application so that already put me in the $400 price point. Might as well go LLSR considering the usage since the cost is basically the same, just more setup effort. I've seen some mention of oil restriction with solid lifters. Is there anything I am missing here?

I'll try to keep this updated as I go. I'm giving it until May before I blow up the 10 bolt. Again.

 

DO NOT use LS7 lifters.

 

I agree

Which is the same way I've scope creeped my way from stock LS1 rebuild to solid roller dry sump LS3

 

Looks like I've got a cam picked out.

Talked to Tony and while his last setup was great, I just don't have the coin to do what he wants to do. And I don't need to make 600+whp and frag the M29 and 10 bolt that much earlier with that much less money to fix it. Cam Motion recommend their 244/256 hydraulic street king cam. I also happened to find the specs of the old Brazilian 416 LS3 stock car motors that ran a very similar cam and had a pretty perfect powerband on stock LS3 heads/intake. Match it up with their link bar lifters and springs and should be good to go and under budget.

https://www.hotrod.com/articles/look...tel-cup-motor/

So in addition to the bottom end above:
C5R timing chain and OEM sprockets
Cam Motion Street King Stroker cam and link bar lifters, springs with titanium retainers
CHE trunnion kit
Holley tall dry sump valve covers w/Summit coils (should clear any future rocker upgrades)
Most likely new assembled LS3 heads from Chevrolet Performance
Stock LS3 intake manifold being fed by my 102TB/MAF/lid w/SSRA
Fuel Injector Clinic 660cc injectors

I supposed I'll need to upgrade from the 255lph fuel pump to a 340 as well.

 

You asked about heads above- Just about ANY rectangular port head will do as they are all based on the 823 casting.

 

I assumed so but wasn't sure, thanks. I am starting from almost zero knowledge of the gen 4 stuff as I had always written them off to oiling concerns without a dry sump.

 

If you are buying new heads, small bore ls7 heads would be a good option if you want to make a lot of power. That would mean you would have to get a different intake though.

If you are trying to be more budget friendly, stock ls3 heads are good enough to make power. I decided it wasn't worth it to clean them up on my build to gain just a few hp. I would have switched to ls7 style. This may affect your piston design though.

 

What I need out of this engine is a minimum of 330wtq by 2800rpm, then power that just builds to ~6500 and will tolerate spinning to 7000-7200 without damage. I don't need max power right now as once the car hits the 470-500 mark I have other areas that need to be addressed. Later on down the road I can come back and revisit the top end for more power. It's just not needed right now. Everything I've read says I should have no problem at all hitting those targets with the 416 displacement and a stock top end and it doesn't look like I'll eat that much money doing it twice.

Ed Rinke Performance Parts had LS3/L92 bare heads listed for $338/head so I went ahead and ordered them. That part number is listed as NLA everywhere else so I expect to see it get canceled. If it goes through it seems like a solid start to slap some good valves in without having to deal with used. Buying complete would have had me replacing springs and going through the rockers anyway.

 

I would think the stock LS3 heads would be good for that.

I'm sure you could spend more on an aftermarket head, or ls3 ported, and gain a little more.

 

Read the spinmonster cam thread thats current. Very easy to achieve this goal with a mild cam and stock ls3 head castings.

 

My .02 is a 244/256 cam in your application Auto X is to large for a 3-6.5K ideal operating range in 2nd gear.
Not an expert, maybe check with Darth or Pat G. I would think something like 234/240 on the small side to
238/246 on the large size would perform much better.
Look at LazerLemonTA 226/236 in his stock stroke LS3 how that performs in his application.
For AutoX a little small is MUCH better than a little to big.

 

Definitely a good point and something I agree with. My only concern is that there definitely is a point at which there is too much torque for autocross. My data system shows tires start to spin at 0.80G which based on what the engine made last year says I should be targeting 525wtq. I don't see any danger of that big cam hitting hitting that too early, so something a bit smaller may be best.

 

And I just got refunded for the heads as expected. On the passive hunt again.

 

Could you please explain why? I'm curious to hear. Thx

 

yeah, same

 

Simply because they're not the best you can buy. If money's no object, there's not much reason to use them. They will do just fine for a whole lot of builds though. Draw you a line in the sand and either stay behind it or step across.

 

I've seen a lot of varying quality of LS7 lifters depending on who makes them. The Delphi ones are $250 or so for a set and seem pretty damn reliable for most applications. But they do seem to leave a bit to be desired on higher lift and more extreme usage applications. Stepping up another $150 seems like cheap insurance. Maybe some of the other guys have more specific info.

For this car specifically, decent size cam will be going in it and while it doesn't get driven much it will spend a lot of it's life in the 5000-7000rpm range. If we get a faster course I would hit the limiter 2-3 times at 6800rpm with only 351whp. This one will be up in the 7000-7200 range and likely hitting it more often. If we get the local airport back next year the video below is a very typical event.

Edit: Tech doesn't like specific start times so skip to 1:17. First run was with a yet-to-be-diagnosed MAF failure and sub-300whp by data. Which is probably a significant contributor to the old motor dying since it started off as an intermittent gremlin.

 

Stock LS3 heads are on the way thanks to grubinski

I'm going to be relatively open here with the expenses since I am trying to keep the costs down. I was cross-shopping the BluePrint 525hp LS3 when I was originally planning this, which goes for $7400 at most retailers. Since my engine is so old and has had some age-related issues I am basically building a 100% brand new engine including sensors and coils etc. Right now for the block, crank, rods, pistons, bearings, heads w/rockers, and all block work and balancing, I'm sitting at $5600. I'm thinking if I can keep everything short of the dry sump setup to $9000 I can consider this a success. As always, all the little things are what can put me over the edge.

 

the blueprint LS3 is with their own casting LS3 head. Prolly china casting I'd stay away until someone has experience with them.

Your car pic( in the signature) looks bad-*** !!!

 

New shortblock just shipped yesterday along with 2116 lifters and a trunion kit. Bearing clearances already checked and rings gapped so I'll just need to put it together. Also have the cam order in. I've decided to home port the stock LS3 intake I bought in order to match my 102 throttle body, so I might as well pull out the stands and add rods at the same time. Also grabbed a 340lph pump to feed the corn which will require the addition of an aftermarket regulator and a return line.

Tomorrow is my last day of work until January 4th so I should be able to get a decent amount of work done. I do need to work on the M3 first (AC compressor, weatherstripping) and do all the welding work on the Camaro before I really get into the engine. But ideally I would like to get everything assembled enough to the point that I can check required pushrod lengths at the end of the break. Seems a bit optimistic as I still need to take the heads to a local machine shop for milling.

After the engine is done I will still need to rebuild the clutch, build the dry sump system, corner weight the car, and send the dampers off to get revalved based on the new values. Part of the SCCA national schedule was released yesterday and the first event is in March...

Anybody want to buy a TDI Golf?