Why Is This Man Smiling?

[Barry_R]

I have time for a couple quick responses....

The big bore was really the only economical way to hit the CID number once my original crankshaft guy pulled the plug on me. Even so, the bore helps on an FE when you have inline valve package - - any flow helps when most of the guys you're against are canted valve. I don't think the bore hurt me much...

I did have too wimpy of a cam. The event timing worked for peaks - but lift was short compared to the big kids. They allowed aftermarket shaft rocker setups (Jesel,T&D) in for next year - so I'll "fix" that.

The original plan/crank had 2" rod journals, teensy pins with DLC coatings, gas ported JE pistons - - lots of swoopy stuff. I still have them - and some will find their way into the next entry. The next crank is a destroked dump truck piece, and is already roughed in.

Next year's rules eliminate the detonation issue, and take some of the extreme mods out of the picture. I think we'll still be playing a tough game against really good head packages - - but might be better off with the lower cubes - - less of a disadvantage.

The dyno load came on really low - like 2200-2300 RPM. They had solid loaded pulls from there. The A/F was much leaner than my Detroit tune due to atmosphere and fuel - - that's why I decided not to push it any further in tuning. The same engine ended up at Kaase's as the subject for a couple chapters in a future book. Once reassembled there it made 759HP on his dyno - - backing up the New York numbers.

The guys at ET are tweaking on a different head combo - - similar, but refined as our experience base improves.

[DavidNJ]

How small did you go on the pins?

Keeping the 4.35" bore, that means a 3.65 stroke! In '04 MPG had a top 5 finish with a 8.2 Dart block bored to 4.25 with a 3.6 stroke. A big bore combination; a 408 in a 302 block!

I would still have liked to see bearing spacers and the crank turned down to 2.25 mains and 1.771 rods.

Are you doing any changes to the combustion chamber? Are you the only entry with ET ported heads?

[DavidNJ]

Are you using tall deck BBC 7.1" rods?

[Barry_R]

Last year I was the only ET ported entry. I don't know about this year. Since both small and big blocks are allowed there could be others????

I tend to use shorter rods than that - - I've never bought into the long rod deal. I much prefer a clean, unbroken three ring pack and a slightly longer skirt. Better ring control means I can back down on tension and hence friction without risking oil contamination to the mixture.

Pins are pretty conventional at .927 - - but they are inboard boss, round wire retainers and are pretty darn short

The rods will stay at 2" 'cuz I already have them. We picked that size for crank rigidity/overlap last year with the bigger stroke. The small main deal is attractive. The FE ain't bad for a big block at 2.75. Next year's rules prohibit shrinking them down...351Ws are 3".

[DavidNJ]

I guess the rods are also .927, which at least is smaller that .990.

Doing some quick math, a 10.17 deck height, 6.7 rod, and 3.65 stroke, leaves a huge 1.645 compression height. The 7.1 still leaves 1.25.

[RICK LAKE]

Barry I agree about the canted valves and the 5.0" bore centered, but a high speed intake charge should take some of the advantage away. A D port flows better than a oval port on exhaust. If some one shows up with a nascar motor they should win. Intake ,heads, cam, and exhaust is where the power is, Where do lighter parts come into play? I would think that a valve spring with 700lbs of max lift pressure would use more HP than a 400lbs at the same max lift. I would think that looking for 5/16 valves with the same size valve diameter with less wieght would make more power. Just like the honda rods 1.88 instead of the 2.0 rods, less friction less power drain. Would not it be more of an advantage to have a motor max out at 200 rpm over the max pull number. Valve float and bounce have a large part in power lose? NO Yes. How about pushrods, I know they flex under load, 3/8 hollow pushrods would save weight, less power drain. There must be a fine line betweenmax flow for a head and max air/fuel mixture speed into the cylinder for a head. Schbeck lifters are a pollymor material with less weight than a solid roller lifter, they make the V shape one for roller cams again lessweight more power to the crank, high numbers. Just some thoughts Barry, Have a good evening, how is the baby? Rick Lake

[Barry_R]

If my wallet was a little healthier I'd go to a Honda rod, .866 pin and a compression distance of 1.35. Leaves plenty of room for rings and enough barrel length so its its not too tippy. Remember - I'm a ring/ring seal guy...anyone want to kick in a few thou???

In a controlled rate of RPM gain contest I agree with Kaase when he says that lightweight parts are over-rated. There is certainly some inertia impact, but as Rick noted this is more of a head and cam contest than anything else.

Valvetrain is a real big deal. Spring losses are not as bad as one would think since they release against the cam with the same energy it takes to compress them - less some percentage for heat and friction. I ran .080 3/8 pushrods last year - they will be .130 wall this year - I don't know if the package will fit more diameter... The T&D that is now legal will certainly help stability...I had considerable flex with only four 3/8 studs.

[DavidNJ]

With those big cams I would like really big pushrods. 7/16 or 1/2 single tapers won't fit? The 7/16 would be 3/8 at the top.

Inertia shouldn't be over 1-2llbf-ft at 300rpm/sec. However, there is a friction difference between a 1.771 bearing and a wider 2.0 bearing. The questions is are small bearings worth 10hp or 25?

[Barry_R]

If I can fuss a bigger pushrod diameter in there I will. The ports rule in that area and the pushrods take what's left. We already run .015 brass sleeves as pushrod tubes, and we get pretty close...there is some offset opportunity, but the rules call for unmodified lifters. Can't run 460's due to oil hole orientation.

Between a 1.77 and a 2" the answer is less than 10 HP. Possibly 5 or less. Same was true for the now illegal little mains. It may be the right thing to do (after all finding 5 HP in ten places gets to be a pretty nice number) but I can't afford to do it this time so the question is moot.

I need to focus my limited resources on things with bigger returns on investment - - heads and cams.

[big-boss]

Barry R
Being new to the forum. I like the way you think. How would one get in touch with you , do you have a shop or website? My e-mail got bounced back.
Why don't you subscribe to the "long Rod" theory? Have you any experience with alum. rods on the street? What are "ET" heads? You are running pushrod tube-Because of Porting? Because of Pushrod ? Thanks

[Barry_R]

My shop/web/e-mail can all be found at:
www.survivalmotorsports.com

ET heads refers to the porting guys I use. ET Performance is within 1/4 mile of my place. They have several of the latest multi-axis CNC porting mills on site, as well as top notch CMM and flow testing capabilities..

[DavidNJ]

ET is one of the top head porters, have a set of their own castings for the LS1 that are considered the cat's pajamas.