HotRodLS1

Fellow members,


I decided to start a thread about the 5.3 LS engine I want to build. This way I can get usefull feedback on the choices I make, so please correct me if I'm wrong, and hopefully this thread can be a source for other enthousiasts.

It's been a while since I decided I want to compile my own LS engine for my hotrod. Since it's a lightweight car (approx 1950lbs) I decided the 5.3 engine with it's grunt is more then sufficiënt and can keep it streetable. Next to this I figured that a progressive powerband is what I need to also be able to set some nice 1/4 mile times. To achieve this I don't want to throw the low end torque overboard. As stated in the title, I also want to keep it reliable and affordable.


Here's what I have in mind:

• Block: A gen IV engine block with a LS2 valley cover en gen IV valve covers. The gen IV blocks are more rigid then the third generation blocks and the baffles on the gen IV valve covers and the LS2 valley cover are a good design.
  
  
• Rotating assembly: GM crank together with gen IV pistons and connecting rods with ARP rod bolt.
  I'm not sure about the pistons and rings yet, but I will be searching for overbore, coated, hypereutectic and flat top pistons and a set of pistons rings with the second ring being a napier ring. I would also prefer a 1.2mm first and second ring, reducing tension, wear and the risk of ring flutter, but I don't think this is available. With the ARP rod bolt (together with checking the big end) this rotating assembly should support 7000rpm shifts.
  
  
• Valvetrain: Turned down LS3 (hollow stem) intake valves and LS9 sodium filled exhaust valves, together with PAC 1518 valve springs, MS3 cam (112LSA) and stock GM retainers.
  The mentioned valves are the lightest available, with the LS3 intake valve @ 83 grams (stock 103) when turned down to 2.00" and the LS9 valve @ 74 grams (stock 88) turned down to 1.55", next to it having improved cooling properties. The PAC springs are among the lightest available @ 62 grams, being affordable and 18 grams lighter then stock. The fact that they are stronger also, together with the lightweight valves, makes me believe they can work with the MS3 cam @ 7000rpm, but I could be wrong. As for the retainers, the 4.9 grams I can save doesn't justify the price and possible wear of titanium.
  
  
• Heads: a pair of ported and polished 706 heads. This heads have 205 intake runners after the work is done and will maintain high compression thanks to the small chamber. This way they should have proper air velocity for the 5.3 engine, keep a decent compression ratio without milling the heads and piston to valve clearance that's save for big(ger) cams. With them being the baseline of TEA heads, a good P&P job and valve job should achieve decent flow numbers.
  
  
• Timing chain: Katech IWIS C5r
  
  
• Oil Pump: Still investigating this. I don't know which oil pan I'll be using yet and therefor I don't know the capacity of the oil pan and the appropriate capacity of the oil pump. At this moment I'm thinking of an 6 qrts 2008 Cadillac CTS-V or an 8 qrts 2010 LS3 Camaro / G8 oil pan with an Mellings oil pump.
  

Furthermore I would like to use King Bearings. Suggestions for improvement are welcome. When something is overkill, I'm also glad to know.

HotRodLS1

To make suggesting improvements a little easier I formulated a couple of questions:

1. Can the PAC 1518 valve springs, together with the lightweigt valves, handle the lobe of the MS3 cam?
2. Is the MS3 cam a good option, or am I off better with another cam?
3. Can this valvetrain setup spin up to 7000rpm, or would it be wise to stay at 6600rpm?
4. Would the use of turned down LS3 and LS9 valves be a good investment, or is it better to spend the money somewhere else?
5. Do you think titanium retainers are a good thing for the money and/or this application?
6. Is it wise to turn the valves down to 2.00" inch and 1.55", or is it better to use smaller or bigger valves in a 5.3 build for the flow?
7. How do you feel about the use of the 706 head on a 5.3 instead of 243 or 799 heads?
8. Could I get into problems with ptv clearance?
9. Is the Katech C5r a good investment at this point, or would you recommend to just use the LS2 chain?
10. Are there certain combinations of oil pan and oil pump that you can recommend?

Hopefully someone can give me some advise

HotRodLS1

p.s. I'm going to use a T5 gearbox (quaife upgraded version) with close ratio gears

gnx7

iTrader: (28)

After you spend all that money you could've bought a brand new crate LS3 with a warranty and have nearly 1 liter more engine. Also you would get it in a few days vs. months for the same $ in the end once you factor in machine work/balancing/assembly. Stock LS3 castings flow over 310cfm which is more than any ported stock cathedral head casting.

The LS3 intake also flows very very well. I've gone 163mph on a stock one with more left.

Please post picture of car

Why not run a T56 Magnum? They can handle tons of power and shift extremely smooth. Weight?

HotRodLS1

gnx7, thank you for the advice.

I want the 5.3 engine in an effort to keep the car streetable. The original engine was an 1.2 liter engine with 60hp and I think the torque of the 5.3 engine will be more then enough for the self-supporting chassis, even with a rollcage.

Living on the other side of the pond, a new LS engine is a lot more expensive. A new LS3 engine would cost well over 10.000 euro. The cheapest would be an second hand engine, but second hand engines are rare and also expensive over here. An aluminum 5.3 truck engine is 3000-3500 second hand and over the last four years I haven't found one with a known historyrecord. That's why I want to build a new engine or rebuild the one I bought.

There are two reasons for me to use the T5. Since I have a little car, the first and most important one is size. The gearbox is a lot smaller then the T56 and next to this the TVR T5 I bought has a very small bellhousing. This way I can keep a manual gearbox in the car.
The second factor is the one you mentioned, the weight of the gearbox. Reliability is the most important thing for me, but next to that I'm trying to shave weight of the car everywhere I can.




It's the car on the right

bigmandengo

iTrader: (21)

A 5.7, 6.0, or 6.2 is just as "streetable" as a 5.3 and if starting from scratch costs about the same.

gnx7

iTrader: (28)

Ships Monday
http://www.jegs.com/i/Chevrolet+Perf...FUlufgodKaoCwg

I'm sure they can ship anywhere in the world. Or for free (as stated) to an East Coast shipping terminal and you arrange shipping from there.

Just put big enuf brakes and enough tire on the car and it will be totally streetable. Holland has a shipping port... it can't be that bad to ship. A mildly cammed 6.0/6.2 will be more fun than a 5.3 built up with a huge cam. The cam ultimately defines the streetability.

HotRodLS1

Maybe to powerfull was a better description.. the power of a well mannered 6.2 will be more of a challenge to drive with the (lack of) ability of this chassis to deliver it to the road.

The government (has to approve the vehicle), chassis, gearbox, clutch and Monza/Vega rear axle can already mean trouble with the 5.3 engine, let alone the 6.2.

HotRodLS1

Well, I have to admit, I just looked at the price at Chevrolet Performance, Jegs is alot cheaper. Still it won't be cheap to get it here however. The LS3 with shipping will cost around €6500,- Importing this will cost €230,-, and the 21% tax over this amount will be €1413,- bringing the total to €8143,-.

HotRodLS1

Can somebody give me input on my 5.3 engine now?

HotRodLS1

I've discovered this isn't true. The weight of the springs is listed @ 62 grams, but the actual weight is about 75 grams. Next to this the reported weight of stock beehive springs varies between 80 grams (grey ones) up to 92,1 grams (blue ones).

I'm leaning towards the PSI 1511ML valvesprings now. They are 67 grams and seem to have a good reputation. Would they be sufficient? Or would the PAC1518 be a better choice? Input on the retainers is also very welcome..

KCS

iTrader: (20)

I'm pretty sure TSP revised the lobe design of the Magic Stick cams. They used to be really aggressive, so I wouldn't have suggested using a beehive spring on it, but now it's different so I doubt there are more than a few people who could tell you if it will work or not.

It's better to be oversprung than undersprung IMO. I have the Comp Cams conical springs in my Trans Am and I like them for the most part. Single spring, super light, and still over 420lbs open (~.060" from coil bind). I posted some info on them a while back when I set them up on the heads. My one gripe was how loose they fit in the OEM retainers and locators.

HotRodLS1

I agree with the idea of oversprung being better then undersprung. Valves coinciding with pistons just isn't funny. As you'll understand I also try to avoid being (to much) oversprung.

The reason I was thinking of mating the PAC 1518's with the MS3 was the reaction of Texas Speed to this idea in another thread:

https://ls1tech.com/forums/generatio...e-springs.html


Having read your reply I've investigated changes in the MS3 cam and Comp Cams conical springs. I couldn't find anything about a change in the cam lobes and couldn't find much information on the springs. The best info I could find about the valve spings is your review and an article.

As you stated, they have good spring pressure. Next to that I believe the design can lessen harmonics, althought I don't think beehives are bad because they are build up in three different sections. Finally they are lightweight, meassuring 73 grams with retainers and valve locks. That's why I'm interested in using this valve springs. Can you tell me something about them?

Did you weight/do you run them with the original (loose) retainers? I also would like to know the cam you use them with, the valves you use and where you've put your redline. Can you also tell me about the effect the spring pressure had on the change interval of the springs and lifters?

KCS

iTrader: (20)

TSP started grinding their cams in house, so their lobes are now of their own design. The Magic Stick cams used to be LSK and/or XER lobes, which were two of Comp's most aggressive hydraulic roller designs. There are a few threads/posts from the TSP guys about how they revamped their cams to be more stable.

I weighed them with the OEM retainers and locks, which I'm pretty sure I posted. I used the same OEM hardware when I installed them on the heads and that's how they are in the car now.

I'll have to look at the cam card when I get home, I forgot exactly what lobes but it was supposed to be an old MIT cam with 232 duration and about .600" lift, but it was a little bigger when I degree'd it in. The valves are OEM as well.

I haven't driven it enough yet to warrant a spring replacement. The springs have been heat cycled maybe a dozen times and haven't seen more than 3000RPM yet. I'll check the spring pressures after I put some miles on the car.

Once I get the clutch broken in and tie up some of the loose ends, I think I can be on the Dyno early this summer and have some results. The car got a lot of new parts so I figure the tune will need to be touched up anyways.

HotRodLS1

I didn't know this, thank you.. I haven't found any threads/posts about this yet, but will continu searching for them later on.


It can be I've overlooked this, but I couldn't find it despite reading your review a number of times. I do know you put the duals on the scale with Ti retainers..

With the locks on the scale and the OEM retainers on top, the actual weight of this valves is 61 grams..


.598 lift to be exact This and the lobe doesn't mean a lot to me when your engine hasn't seen over 3000RPM, but your opinion about the lobes the springs are compatible with does.. (When using hollow and sodium filled stems) It does explain why you haven't updated your review yet.. and it's been 1,5 years ago. Time flies, doesn't it?


That would be a nice thread..

KCS

iTrader: (20)

Had to rummage through my photobucket account, but I found it:



That's the conical spring with OEM retainer and locks.

Yeah it sure does! I travel a lot for work so I really only get to work on the car every now and then. Plus I have a Mustang I'm building including another engine to go into it.

The dual springs I had on the car before had about the same seat and open pressures as the conicals and never seemed to have any issues. The conicals are lighter and have a higher natural frequency, so I'm pretty confident they'll be fine. We shall see soon enought though.

HotRodLS1

Just seen the advice of going 2.02" intake and 1.60" exhaust on a 5.3.. didn't know it was possible

NJmooch

My truck will be coming out of the shop this week. It is a stock 5.3 LH9, factory 243 heads, with a Pat G supercharger spec cam. The supercharger is not installed yet, so you will see what a cam swap can do with a stock 5.3, along with PAC 1219X beehives, 7.4" Brian Tooley pushrods, C5R timing chain, Melling oil pump, etc.

I would recommend using the 243 heads with the 5.3, and get a custom cam to suit your needs. I will keep you posted on my results.

HotRodLS1

I'm interested.. what grind? Why PAC 1219X? Why the C5r timing chain? What Melling oil pump and also.. why? I'm just trying to understand..


What's the advantage over the 706 heads? After a P&P job the flow should be more then sufficient for the 5.3 engine.. right? I'm curious what results you get..

MuhThugga

Have you looked into the McLeod Musclecar 5 and the Tremec TKO 5 speed transmissions? Just more options for your consideration, but I don't know about availability across the pond.

As for the 5.3, right on. I do grow weary of people asking about building smaller engines and everyone responding with, "Just get a 6.0/6.2." With that said...

You don't seem like you are trying to make gobs of power, so you could get away with a factory Gen IV bottom end and be perfectly fine.

I'd probably forego turning down the LS3 and LS9 valves in favor of picking up a pair of 243 heads milled to achieve a 10.5:1 compression with Cometic .040 head gaskets. The 243 heads flow very well out of the box, and you won't have to spend a ton of money on buying different valves and having them turned down. A valve job and some bowl work on the 243s should provide adequate gains if you won't be happy with simply milling the heads and bolting them on.

You could save some money by simply going with the LS2 timing chain or the LS2 IWIS timing chain. Just remember to also get the LS2 timing chain dampener.