My 57 Chevy feels the need for NO speed.

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swampratt

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Yea I drove it like I stole it for many years.
2 different engines 4 different camshafts it has seen 7600 RPM.

Now the other day it decided to break a spider gear in the 9" Ford rearend.
Fixed that and pulled the 3.70 gears and stuck in some 2.75 gear set i had ready to go.

Lots of top end now.
On the way home from the cam shop I fading over to get into the slow lane on I40
And I looked in the rear view mirror..Plenty of room cars way back and I seen a flash and something black and rubbery flipping in the air behind me.

Then it hit the pavement and shattered into a million tiny shiny pieces.
I looked over my shoulder and sure enough my back glass had blown out and shattered on the highway.

I went to Regal Plastic and they cut me a rectangular piece of Lexan.
I now have a glued and screwed Lexan back glass.

Weight savings there and less than 100 bucks spent.

Fast forward to today.
In the driveway I hear a header gasket leaking.
I tighten the bolts and more ticking but odd ticking.

I pull the valve cover and my front rocker arm is broken the end off that goes over the valve.

Luckily the retainer and keepers are secure.

I stick another rocker in it and notice it sits a bit higher.
I adjust it 3 times it is the same all 3 times.. well good then.

I fire it up ..sounds better still has the exhaust leak then it went POP POP POP!

I shut it off and pull the valve cover again.
The wire retainer on the lifter had let go at some point and is missing.
I pull the intake and decide if all the lifter pieces are there i will put it all back together.

NOPE! seems they went down into the pan or somewhere.
Time for a tear down.

I decided to do an experimental cam again.
I had a 280H in it 230@ .050. 110LSA
Before that I had a 268H on a 112 LSA and before that a 268H on a 106LSA.

The 112 gave me 18 MPG.
I had a 268H ground today on a 114 LSA I will installit way advanced which I did with the others 102 intake centerline. Keep cranking pressure up for low end power you know.

I may not be able to advance this one to 102 but will give it a shot.
106 intake centerline would be fine though.

Hopefully when i get it back together it will be done taking a dump on me.

:)
 

Cowbaby

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Only understand about 3/4th of it. But I do know this gasoline now days is not going to put up with timing advanced too much before TDC, Not enough dino fart as that old Eythy where you could start popping way before you got there even up until right before detonation trying to milk the last amp.
 
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swampratt

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I do know this gasoline now days is not going to put up with timing advanced too much before TDC

The gasoline today is fine for high compressions and quick timing curves.. it is more of a combination of parts and how you romance those parts as to how well it will tolerate increased cylinder pressures and loads.

I have ran 11.9 compression with carbs and old school iron heads with small cams without issues.

91 octane fuel for racing and I have used 87 for just part throttle cruising.
But know I do not just buy parts and slap them together.

I just ordered a rebuilt LQ9?

I ported some LQ9 heads for a buddy and it got a nice little cam upgrade.
More cylinder pressure after the cam swap and 7000+ rpm ..More power everywhere.
109 LSA on that LS cam.
Another custom grind.
Worked very well in his 4000 lb truck.. Carbureted on top of that :)
 

tRidiot

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I ported some LQ9 heads for a buddy and it got a nice little cam upgrade.
More cylinder pressure after the cam swap and 7000+ rpm ..More power everywhere.
109 LSA on that LS cam.
Another custom grind.
Worked very well in his 4000 lb truck.. Carbureted on top of that :)

Well, the LS9 stock with an Escalade tune should net me about 40 more HP than my stock L59 did - I didn't need or want any real HP upgrades, as most of them are at higher RPM and this is a grocery getter and family hauler. I haven't probably gone above 4k RPM in years on this truck, lol. I'll be happy if I can pull more than 12MPG out of it on the highway, honestly. If it does more than 15 I'll be ecstatic. 4l60e is getting rebuilt with some upgraded 5 pinion planetaries, I don't think I need much more than that for my plain old Tahoe.

I'll just be happy if it ships in 2 weeks like I've been promised, then I can get it in and running by mid-May and have it available for vacation in NM with the family. That right there will save me near $2k on a rental vehicle.

So here's hoping...
 

swampratt

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I am shooting for 20MPG with this 268H on a 114 LSA NO overdrive.
Carbed also.
Seems the best I can ever do is 18 MPG from my V8 carbed stuff and keep excellent low end TQ without sacrificing too much mid range power.

The LS heads are punks when it comes to MPG in a truck. You do not get great atomization with the smoothish runners and that
rocker arm boss in the intake runner makes for a dead spot and some reversion behind it.
Porting the runners a bit there and making them very rough helps in the power and MPG department.

If I was FORCED to run an LS I would do the 6.0 and run the 706 head.
I would port the 706 though :)
I have ported 706 and 317 heads only so far for the LS.
I have ported all kinds of old iron heads and even a Geo Metro head HA!

A really good read on the LS and head swap with dyno numbers etc.
http://www.superchevy.com/how-to/en...-numbers-from-our-stock-ls-cylinder-head-test
 

tRidiot

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The problem with the 706 heads is most are made by Castech and there was a manufacturing defect which led to corrosion and coolant leakage into the heads. This is what got me in trouble with my 5.3L, it's been going on for several years.

https://ww2-secure.justanswer.com/uploads/Bluegorilla/2008-12-05_142924_Coolant_loss_5.3.pdf

So that made up my mind - absolutely NO Castech heads. The 706 is the most common, but there are reports of the 862s also Castech manufactured having the same defect. There are SOME 706s out there NOT manufactured by Castech, but the only way to tell is to pull the valve cover and look for the casting mark. Most of the remanufactured engines I've found out there seem to come with 706 heads and even if the remanufacturer claims they've been inspected, reworked or 'repaired'... I don't want to run the risk of having to deal with this again.

Therefore, the 6.0 LQ9 and 317 heads is the route I decided to go. The flat pistons give it a slightly better compression ratio than the LQ4 and I'm just looking for longevity and reliability at this point. Mileage is a concern, HP is a distant dark horse for this one. I do run 3 alternators, so it'll be nice to have a little more power than my 5.3L L59 did - although I never felt it was 'anemic', I'm sure I'll notice the extra 40+ from the bigger motor. Aaaaand, this one won't have 275k on it, either, lol. The lift @SlugSlinger was so incredibly nice to help me do a couple years back ate into my mileage some more, so I'm just gonna cross my fingers, I guess. Having a 10MPG vacation vehicle for the family may hurt a little bit, but for me, getting away from even the remotest possibility of the Castech 706s was paramount.

Later I may upgrade the intake and exhaust, buy a tuner of my own and see about working with it a little bit to fine tune things - but I may just leave it pure stock, if it runs well and doesn't guzzle like Kid Rock on tour. :lmfao:
 

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