powerpigz-51

Alrighty....looking for some forum advice on my next project. I am done collecting the parts, am halfway done porting and ready to start tearing my top end apart. Here is the build......

85 L98
350
TRW flat tops <X> amount down in the hole.
XE 262 flat tapper 218° / 224°. Max Lift w/ 1.5RR: .462" / .469"
Edelbrock RPM heads 64 cc
Edelbrock Hi Flo 1205 port matched
Accel runners (unported)
ported plenum
52mm Throttle body
24 pound Bosch 3
AFPR
Edelbrock head gaskets .038
1.6 Comp roller tips
.100 longer push rods
Pacesetter short tube LT1 headers, no cat true duals
4+3 3.07 gear
I also Have 1.5 roller tips....so I can also run a split set if I want
My overthinking mind is wondering whether or not to siamese the Accel runners, leave them be, or partial siamese. To match the RPM capabilities of the combo and realize the limits of the long tube runners, I am thinking partial siamese. I currently am running a full siamese set of stock runners (on my current set up, mostly stock) and my car has a low speed driveability issue (coasting down) that I want to avoid. And I can burn my own chips. Watchya all think?

Race Prepared

Consider a larger cam and different rear gears. What heads are you running?

powerpigz-51

Already have the cam, I think it is a good choice for what I am doing. Edelbrock RPM heads. I know, AFR's are better. I am done buying parts, time to build.

rklessdriver

I would run the 1.6 rockers to get as much lift as possible with that flat tappet cam.

I would siamese the first few inches of the Edelbrock runners.

Use as thin of a headgasket as you can get (Fel Pro 1094) to get some compression.

Check your rocker geometry and buy the correct Pushrods....
Will

powerpigz-51

Siamesing the runners a few inches is what I was thinking. Not knowing how far in the hole my pistons are, I am thinking I am playing it safe with the .038 gaskets. I am going from a 76cc chamber to a 64cc, I am thinkin' that is enough compression for now. The 1.6's all the way around sounds good...need the lift for sure. Rocker geometry will be checked and corrected if need be, as well as the cam dialed in with a wheel. My car runs so good now, I hate to tear it apart. I average 21.5 MPG....drove over Sherman pass last week, it was 102 degrees, uphill, temp 195, downhill...170. Could use some more top end!

DanielRicany

If the block has never been machined, the deck height should be 0.024". Plus keep in mind, your quench can be as tight as you want, as long as you have the proper piston to valve clearance. So, I suggest purchasing 1 head gasket and measuring the piston to valve clearance with the 1094 to see if you are in the safe zone. Keep in mind you will need a flat surface with the 1094, very flat. 0.015" + 0.024" = 0.039" quench area. Which is perfect. Typically people aim for 0.035" - 0.040" quench. This will allow you to run more timing without detonation. The quench effect stops working at 0.060".

powerpigz-51

With what I have specified for parts, running 1.6 all over, and a few inches (lets say 3) of runner siamesing.....where do you think "The Wall" will end up?