bortous

This posting is for my friend down here in Australia who has one of the special edition VE HSV's which came with the LS7 engine.
The engine is apart at the moment for some much needed work to get this thing really moving.
The purpose of this build is to be a weekend warrior and not a daily and therefore the engine will be quite aggressive.
This is the combination:
CNC LS7 heads with 62CC chambers Compression is around 13:1.1
MSD intake
3:73 gears
stall converter will be ordered after cam selection is made.
248/262 .680 .665 112 LSA +3

Combo looks good to me but my knowledge is limited.

What do you guys reckon?

Che70velle

iTrader: (6)

ASSuming he’s staying with a hydraulic roller? Cam specs look good to me. That’s a lot of compression, which I am a fan of. I’m running 12.42 in my 434. What fuels are available to you guys down there? He left bottom end alone?

bortous

He is running pump e85 like me.
Good thing about the e85 here is that it's consistent all year round with an 85-90% ethanol content.
We have the same fuel as the USA although the octane ratings are different. For example your 93 octane is the same our 98 octane fuel. Different measurements.
And yes it's a hydraulic roller.
Bottom end is stock.
His hoping there will be enough PTV clearance. If not new pistons will need to be fitted.
I like the camshaft selection too.
Looks like the IVC of 53 and EVO of 66 suit the compression he has.
He was telling me something with high compression you need to open your exhaust earlier and extend the IVC a bit later
Should make some crazy power.
I knew of this guy down here who had 17.1 compression NA.
on a 402 he had to extend his IVC to 56 and his EVO to 69 if i remember correctly because of the compression.
Apparently if you don't it can make the engine not perform as well

fnbadaz06

What rocker setup is he planning to use with such a big lift hydraulic cam ?

KW Baraka

iTrader: (7)

I'd bet a dollar he'll be using Yella Terras.....

KW

bortous

Yella Terra platinum rockers.
These are rated to 900LB open spring pressure which is more than enough for his application.

bortous

You won the bet.
I hope you have changed those mid length runners back to the long version by now!

jayyyw

62cc head is more like 12:1 compression. How is he calculating 13:1? Camshaft looks good. Not a fan of YT rockers or the MSD intake.

Bill00Formula

iTrader: (4)

With a 4.125 bore and flat top pistons it was my understanding that 64-65 cc equaled 12:1 compression. That's what was on my 427.

fnbadaz06

66cc chambers on my WCCH Stage 2 OEM heads (.030 mill), with standard OEM head gaskets, came in at 11.7 static compression.

bortous

Why don't you like the yella terras and the msd?
What would you recommend instead?
62cc would be close to 13 on a 427.

bortous

So 62 cc chambers would equal?

rkupon1

iTrader: (3)

I sure wish we had e85 here in nj...i prolly would have pushed the envelope with a solid roller and drysump set up. Along with e85, man thatd make sum power

01CamaroSSTx

iTrader: (3)

Assuming a flat top piston, a zero deck and a 0.050 compressed thickness gasket I get 13:1

ColeGTO

iTrader: (3)

https://www.summitracing.com/newsand...ion-calculator

4.125" bore
4.000" stroke
62cc Head Volume
5cc Piston Volume (standard flat top with valve reliefs)
.000" Deck Clearance
.051" Head Gasket
8 cylinders

12.2:1 Static Compression
427.65 Cubic Inch

What this calculator does not take into account is:

1) "crevice volume" (distance from piston top to the top ring
2) Head Gasket Bore


You can also try this one. I get the same result.

http://www.csgnetwork.com/compcalc.html

jayyyw

Not on a SBE LS7. 12:1-12.3

I would use the T&D adjustable rocker that mounts on the stock pedestal.

MSD is the better of the plastic intake manifold offerings. If you have clearance concerns, I'd run the MSD. What are your goals for the setup?

I made 646whp on a SBE LS7, LME ported stock heads, milled to 63.5cc, cometic .041" headgaskets, a Holley Hi Ram, 243/258 .660/.660 114+3 cam, 1-7/8" headers, and e85. That setup trapped 142.5mph in 2000DA.

Che70velle

iTrader: (6)

Nothing wrong with the YT rockers when setup properly.
Lots of guys making 650-680 with Mamo MSD.
Hi Jay.

01CamaroSSTx

iTrader: (3)

I just rechecked and get 12.2:1 also. I didn't take into account for the 5cc valve reliefs.

jayyyw

Hi there

bortous

Do you know if mamo uses the ultra lite pro's or the pro street in his builds?
Looks to me they are the ultra lite pros.