mrestrictrplate

iTrader: (2)

Hello. I have a 87 roller l98 and bought a set of ported twisted wedge heads. Car will have a stealth ram 1 5/8 headers 700r4 2400 converter 3.23s. Any recommendations for a cam? I'd like to run in the 12's thanks for your input. Chris

BadSS

I ran a 218/228, 0.489/0.501, 110 spread cam with a near identical set up and ran 12.3s in cool weather. My exhaust wasn't all that, 1.625 shorties and a single 3" so the wide split duration helped me a bit. If you run a 3.5" or 4" exhaust to a single in and out MagnaFlow or Borla Sportsman, I'd run less of a split - maybe something in the 222/226-110 range. With the G1 Twisted Wedge 13-degree or the G2, 15-degree intake valve you're going to be limited to 230 degrees intake duration and .530 intake lift on a 110 lobe spread with standard flat-top pistons.

Twin_Turbo

iTrader: (25)

that's why I run a zz409 in one of mine,

226/226 duration @ .050
.520/.520 lift with 1.5 roller rockers
112 LSA

It's about as miuch as you would want to run with G1s without resorting to flycutting or special pistons.

TTOP350

iTrader: (8)

I ran SLPs old " big" cam with my tw heads.

Twin_Turbo

iTrader: (25)

What are the specs of that cam?

ASE doc

For what it's worth, I run TPIS's ZZX (240/240@.050 560/560 112 LSA) with my G2s and flat top pistons set at .010 deck height with .039 of gasket. The key to not breaking things is to check valve to piston clearance before you put the valve train together. I have .100 clearance at overlap.

The ported G2 heads and this cam is way too much for even a big ported TPI. It makes power but the intake runs out of wind way too soon. Even though TPIS designed the ZZX for their own TPI racing effort, I expect it will do much better with a ported Eddy Pro Flo XT on top. It would also work well with a Miniram or single plane, though the shorter runners would prefer a closer LSA (like 108).

383RAT

Well I had that same set up except for different intake & 52mm throttle body when I had
Advertised Duration (Int/Exh): 262/270
Duration @ .050 (Int/Exh): 211/219
Gross Valve Lift (Int/Exh): .507/.515
LSA/ICL: 112/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1600-5600

That got me 12.9s

When I went to better gears and larger injector. 58mm throttle body
Needs 9.5:1 comp. min. Requires 2500 RPM stall converter in most applications and needs 3.42+ gearing.
Advertised Duration (Int/Exh): 282/290
Duration @ .050 (Int/Exh): 231/239
Gross Valve Lift (Int/Exh): .535/.550
LSA/ICL: 110/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 2400-6400

That got me 12.4

Hope that helps

mrestrictrplate

iTrader: (2)

Hello.. You were able to run those cams without piston to valve problems or did you grind the valve reliefs? Thanks Chris

383RAT

Mrestrictrplate,
Actually I have no idea what the original pistons look like. I bought an unfinished project car. I do know what pistons are installed. I have no clue if they are dimensional the same as stock. Here is the piston info.
SRP Part# 138103
1.125 Compression distance
+16cc Piston head volume
403 grams
Forged Dish / 4.030 bore

With the pistons above there was no grinding needed.

ASE doc

I was able to run the ZZX without interference issues(had .100" clearance at overlap). No grinding of the valve reliefs. As I said in my first reply to you. The most vital step is checking valve to piston clearance before you assemble the valve train. This way if you have interference issues, you get to find out before you spend the time assembling everything just to have to tear it all back down, and more importantly before you damage parts.

On my 406 build which I hope to do in the next few years, I will stay with the G2 heads. I'll run them with 13cc dish pistons to set CR at 10.5 with the 3.75 stroke. I also plan to run .001 deck which will make valve to piston clearance a little more of an issue, especially if I go more aggressive on the cam or run 1.6 rockers with the ZZX. Using pistons with 2 reliefs rather than the generic 4 relief pieces in my 355 will help. If there is an interference issue on the new motor, I'll just have the pistons fly cut for clearance then shave the heads as needed to restore CR to 10.5.

Of course there is big difference between the G1 and G2 Twisted wedge valve angles. The G1s have 13 degree intake and 23 degree exhaust, the G2s, which I run, have 16 degree intake and 18 degree exhaust. This means that what might work for one may not work for the other. Again, you have to check clearance before assembly.

badgta

iTrader: (4)

XFI 292 HR13

Twin_Turbo

iTrader: (25)

For a 383+ hell yes but he'd need fly cut pustons. Crower makes a nice tool but it's limited in how deep it will go.

Is this in respect to g1 or 2 heads? Ase I thought you ran g1s?