429 sbc ls build

[randy331]

I like those Mahle pistons with the 1mm 1mm 2 mm ring packs. Nice low drag stuff without modifications.

Used a set in a 408 cube ls. ( an actual build I did not just "speced out" )

But, I got one of the Total Seal piston ring grinders for these little rings. Got tired of the hand grinder.
If you don't have a ring grinder, I'd suggest doing the fitting at Joe's and pay him for the use of his, or have Katie do it.
It's worth it.

Who's doing the work on your heads ?

Randy

[MadBill]

I was poking around and found something real cool....you can set users to 'foe' list and never even have to read their nonsense.

from the FAQ page:

Friends and Foes

What are my Friends and Foes lists?You can use these lists to organise other members of the board. Members added to your friends list will be listed within your User Control Panel for quick access to see their online status and to send them private messages. Subject to template support, posts from these users may also be highlighted. If you add a user to your foes list, any posts they make will be hidden by default.

Yes, I've been implementing it lately. It helps not having to read through long, long posts by people that aren't offering any thing but regurgitated theory they read somewhere. Until they create a fact and fiction section on speedtalk….it's your best bet. And I'm sure you've probably drawn the same conclusion that I have. That the longer the post(in general), the more fiction and bull$hit it contains.

There's a FAQ tab? Oh yeah, there it is! Well Bleep, never noticed it in my 13 years on S/T!

[slo-svt]

I like those Mahle pistons with the 1mm 1mm 2 mm ring packs. Nice low drag stuff without modifications.

Used a set in a 408 cube ls. ( an actual build I did not just "speced out" )

But, I got one of the Total Seal piston ring grinders for these little rings. Got tired of the hand grinder.
If you don't have a ring grinder, I'd suggest doing the fitting at Joe's and pay him for the use of his, or have Katie do it.
It's worth it.

Who's doing the work on your heads ?

Randy

I have already "worked" the set that have .085 milled off of them. They are cnc ported from the factory but have a swirl dam on one side of the guide boss. I removed he swirl dam and dropped the ssr probably .100. The intake lines up really nice so I didn't do anything to the entrance. The exhaust port is untouched I plan to do the other set pretty well the same. As far a ring grinder I use a circular saw blade sharpener from harbor freight lol. I cut a piece of maple with a groove in it that the rings sits down in really nice. I am going to get some stuff to get a port mold of both sets before I start on the factory set though. What do you use for you port molds?

[slo-svt]

Here is a couple pictures of the milled heads last year when I installed the new heads and 1st cam.

[slo-svt]

Funny! I figure your build will shake up the world.... Not. When you post the results of not having 800 and more than 740 at the crank I hope you'll be happy. Same as CGT when he list his results also. There's more builds that are similar than your build being a one off.

Thanks for the input chief. Will the Rowdy Yates Chinese heads push me up towards that 800 mark?

[KnightEngines]

You'll want to redo the valve job on the exhaust, bump up the throat to 91-92% & open it up so it tapers out to the manifold face.
It'll want the turn laid back a bit & roof raised.
As it sits you won't get where you want to be.
To turn higher rpm you need a good ex port, cant crutch it with cam - the extra duration required will screw up overlap & hurt trapped ve.
Also, bow to the consensus & run a solid cam, quit debating it, the guys that know have told you, unless you're a bunch smarter than them or have $$ to burn for spintron time & parts a solid is going to be required.

[A_VAS]

did you decide against re-using the stock titanium rods? I have a full used set here and debating the same thing...everybody says the coating wears off the cheeks and should not use them. I don't know how to tell if they are useable or not.

I'll measure the ring depth and groove depths to record the info, have a set sitting here now

[slo-svt]

You'll want to redo the valve job on the exhaust, bump up the throat to 91-92% & open it up so it tapers out to the manifold face.
It'll want the turn laid back a bit & roof raised.
As it sits you won't get where you want to be.
To turn higher rpm you need a good ex port, cant crutch it with cam - the extra duration required will screw up overlap & hurt trapped ve.
Also, bow to the consensus & run a solid cam, quit debating it, the guys that know have told you, unless you're a bunch smarter than them or have $$ to burn for spintron time & parts a solid is going to be required.

Thanks for the input on the exhaust Port. The set I posted a picture of Has about that on the throat with 50 degree seat. I intend on keeping it that way or possible doing a little steeper exhaust seat. Any more input on the lifters? From what I understand the Copo uses a Johnson drop in hydraulic lifter (I thought I read they are preloaded at .050) with psi valve springs and have a max rpm of 8000. Sams 441 uses shimmed ls7 lifter basically bottomed out on a Spacer and turns mid 8000s(I understand Sam’s isn’t a great comparison but it does make me feel as if the main lifter components are capable of turning those speeds with the correct spring)

[slo-svt]

did you decide against re-using the stock titanium rods? I have a full used set here and debating the same thing...everybody says the coating wears off the cheeks and should not use them. I don't know how to tell if they are useable or not.

I'll measure the ring depth and groove depths to record the info, have a set sitting here now

I intend to re use the factory rods as long as joe tells me they are ok when I drop them off next week. Visually they look fine to me. I may have to ask him what he looks for on them. I do recall I guy on here a while back buying up ls7 rods left and right and running them in something. May see if I can dig up one of those old threads here in a bit.

[Rowdy Yates]

Yeah they would..... Needs a Cam that gets to around 8200 oh I forgot Mike Jones already did that already. Heads were meant for 800 on a 408 not a 429. On the engine specing with over 10 people helped without any problems and reference, with dyno results. Yeah I figured if you build engines for the EMC or work for a dealer you know it all. Which is saying quite a bit with the LS that has a entire forum. You can talk about rods, pouring molds for heads and anything else dealing with a Ls engine. Your just doing your own work which is great but nothing new as there's plenty of people who've done the same basic things in building up the compression with milled heads and Cam change. Honestly sounds like Johns build with more compression and a Cam that's so similar your just using a hydraulic roller and John used a solid. Spec' that when I read your build list.

[randy331]

I am going to get some stuff to get a port mold of both sets before I start on the factory set though. What do you use for you port molds?

I don't have time for molds but,... I "spec" this for port molds when others ask what I "spec".

http://www.uscomposites.com/moldmaking.html

Randy

[midnightbluS10]

I think you may be 75-100HP shy of your power goal with your combination in a low hood profile Corvette and a regular street driven car in a N/A engine format.

It will take a long duration high lift camshaft to get the engine producing those kinds of power with some pretty big flowing heads and a LOT of Compression! It would need something like a well setup Holley HIRam intake. Factory vette cams can operate at 7000rpms easily because they don't have the larger spring pressures a camshaft that would be needed to feed this level of power and higher rpms it will take to get there.

I don't believe there is a hydraulic roller that can do this for you even with the best valve train design.

If you want to see the LSX that can get there you need to take a look at the Camaro LSX COPO engines and you will probably realize why they would be a difficult BITCH to drive dailey on the street.

I am not trying to pupu your project but I think based on street driving acceptable manners and the restrictions of a low hood clearance and cooling issues on a ZO6 Corvette you may want to look at lessen your expectations for power level and driveability and plan your build around a workable solution
-OR slap a supercharger on the engine like GM did! JMO

Since I've never built one I can only show what others have done but here's a 770hp stroked ls7 with 40 more ci(468 total), 12.25:1 compression, 25*/27* duration 115 lsa and over 400/245 cfm heads from Mast Motorsports. And around .660 total lift on a hydraulic cam & lifters.




http://www.superchevy.com/how-to/projec ... ower-of-7/


Its doable. Even if their dyno is happy.

[steve316]

I haven't see any data from testing that indicates increasing the cu. in. of a given engine decreased the HP. Also have made over 800 hp with heads that flow a lot less. I'm liking the testing rather than copying somebody build. great post

[A_VAS]

Have you measured the ring groove depth?

I just took some measurements....needed to do it at work where I could find a drop gage with a fine enough tip to fit the groove.

Top ring groove:
depth 0.1552"
width .0399"
Top Ring: 0.138 depth x .039 thick (looks barrel faced Moly)

2nd ring groove:
depth 0.1572"
width .0399"
2nd ring 0.131 depth x .039 thick Napier

I checked the rings with calipers, so can't get super accurate. The grooves I checked with a needle on a drop gage, surface plate...so I am pretty sure they are accurate. At first I assumed they were same depth, but repeated measuring the 2nd groove is .002" deeper.
The 2nd ring groove isn't just a square cut groove, the bottom edge of the groove is relieved in a stepped area.
hard to focus on this pic but shows the arrangement.

I've noticed the 4" stroke part numbers in this arrangement, most don't use the oil support rail...so that is kinda nice they can squeeze this stack in those ~1.110 CH pistons without running into the pin bore.
this part pictured is 3.622 stroke 4.070 bore

[Newold1]

Those dimensions on a Mahle Powerpak LS piston would be for the 1mm, 1mm, 2mm ring sets. The second ring is a Napier style ring and needs just a slightly deeper ring grove to accommodate the napier ring when it twists slightly i believe.