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Brent,
Looking forward to some pictures and more detail as the build progresses. It is amazing how much low end torque some of our engines have. Going through town is manageable, but it is on those windy roads that we really get to experience what the engine can do. I thought that about 10.5 was the max that you could go on pump gas. Did not realize that you could go up to 10.8. |
The block is on it's way and will spend several weeks in the machining queue.
1795, there are a lot of variables involved including chamber design, cam specs, and even the area where the engine will be shipped. |
Oliver rods are on the way.
Ferrea valves are ordered. Having Keith put 5/16" guides in the heads. Camshaft is also ordered. Custom Bullet Cams billet solid roller, 270/280 @ .050", .440" lobe lift. :) |
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Are you going for his new 'golf ball' port textures? :confused: |
I can't wait for those gratuitous rod bearing pics. Ooohweee baby! :LOL:
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2.250/1.750.
Valves won't be here for about 3 weeks since they are custom pieces, so we'll see if Keith has his new head machine up and running by then. The heads flow 360/370 with the existing program, so I'm not sure if there is much room for improvement... |
Rod, I'll take some rod bearing pictures just for you....ever seen a coated bearing? ;)
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Or do you mean the intakes flow between 360 and 370?:) |
I meant between 360-370 on the intake side.
Tony sent me a flow sheet from a typical Stage 3 head: .3 212 172 .4 268 210 .5 313 240 .6 331 266 .7 353 276 .8 371 281 .9 376 285 Those are with the 11/32" valves that they normally use. The 5/16" stem valves will be lighter, which will be good since it will allow me to drop the spring pressures down a tad, plus the smaller stems *may* add a few cfm to the mix. If you extrapolate the flow numbers up above for a .750" net valve lift, you'd be somewhere around the low 360's on the intake side and high 270's on the exhaust side. Keith will flow these actual heads for me so we can see where we are with the smaller valves, and I usually flow them here as well when I get them. Not that I don't trust Keith, but it's good to compare flow benches/dynos/etc when possible. So far, the SF600 that I have access to has been pretty much dead on with Keith's SF1020. |
I guess that should have been interpolate instead of extrapolate.
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Do you scuff them a little or use as-is?
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As is....
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Overkill for Cobras but do you have much call for DFL coated bearings? Or that just 'Cup and ProStock stuff? I remember Mahle offered most piston tops and lands coated.
Are those Kings? |
This is about the extent of the coated bearings that I use. These are clevites. What's fun is that I have to keep standard, .001", and "X" bearings on the shelf so the clearances can be adjusted. At $150 for a set of coated main bearings, it can add up.
Mahle pistons have the skirts and crowns coated, they are nice pistons. This build will get a custom set of diamonds which will be lightened, coated, and will feature a custom ring pack size. |
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Marketing was cake compared to that...:JEKYLHYDE Nice parts choices for this build-shooting for 680-695? |
Oh man. Those are beau-ti-ful. I'm not a smoker, but boy, I sure could use a cigarette. :LOL:
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What is this motor for?
bylkins Brent I see you are looking for 7,000 rpms and high HP. Doesn't your buyer know that TORQUE moved his car and HP is just a by product.
If looking for a quick revving motor, going to titanium rods would save alot of weight a\or even aluminum rods if he is told about heating up the motor first before beating on it. Are you going with a roller bearing motor for the camshaft? Lifters are .904"? Pac and Comp have new beehive springs out but are limited in the .700" lift range with a min coil bind. I don't see why guys are not looking at 4.280 bore motors with 4.375 crank shafts. We have a couple of guys here racing and these motors make stupid power 760-800 hp and also run to 7,000 rpms but not recommended. Piston speed gets a little high. This is my next motor with TWM 58mm I also have a set of stage 3 heads with KC ports. I got 368 on intake with 11/16 valves. I am looking at 8mm intake valves at 2.25". will stay with 11/16 on exhaust. I don't see a great differents between the 2 unless more work is done on multi vale angles. The valve where not back cut only 3 angle setup. You can pickup 5-10 cfm in the low range with cut back. I am going with a little stronger beehive than the old 126 springs for BBC motors. These springs do drop off at about 5,800 rpms with hydro lifters. Trick here is to have them pump up and run total.015" valve lash. They will still lose power to 6,200 but not like the correct adjustment or hit the pistons. The other help is running 75-80 psi of oil pressure. Hope your guy is going dry sump or an accusump pre oiler. Sound like a good build. Looking forward to seeing it. Rick. Ps that street twim works great. Going to buy another one for TA. |
Rick, we seem to be on different sides of the playground on a couple of subjects....especially with the horsepower vs. torque thing....:LOL:
I've done the 4.280" bore with the 4.375" stroke engines, that end up at around 501-503 cubic inches. This one is pretty close to that at 496, and I'd rather have the displacement with the larger bore and shorter stroke on an engine like this. Titanium rods would be nice, but just not worth it at over $4000 a set. Aluminum rods are cheaper, but with a 4.250" stroke, I'd say they'd probably hit everything but the water pump, and honestly, I'm just not comfortable with using them on a street engine, especially a customer's street engine. I'm using Oliver rods on this build, with small block Chevy rod journals. They are slightly lighter than the same rod with the BBC rod journals and the 2.100" journal keeps the bearing speed down. As for roller cam bearings, they are unnecessary in a lot of the engines out there. The only real reason to use them is if we go to a 50 or 55mm cam journal, where there aren't a lot of cam bearing choices available. This has changed slightly over the years though, and there are lots of babbitt bearings out for the larger cores. We are looking at probably 650-660 lbs open pressure with this cam, 700 at tops. Certainly no reason to hop over to a much more expensive cam journal. I've got my eye on a set of PSI circle track valve springs, so that's probably the direction I'll head. I do plan to put bronze lifter bore bushings in the block though as they will lend more stability to the lifter, especially at the lift we'll be using here. The owner is supplying me with some bushed Crower lifters that he bought new just several hundred miles ago, so we are going to use them. I normally would choose a .904" lifter, but the .875" lifters will suffice here. The underlying theme here is that it's a street engine. Every component that's been chosen has been chosen with that in mind (although we are on the fringe with a lot of them), but also chosen to make sure that the engine will be reliable at high rpms. Using custom 5/16" Ferrea valves on this one and it will be interesting to see if the flow picks up with them. They are certainly lighter than the 11/32" valves. BTW, I also spec'd a McLeod twin disc for him, they are certainly great clutches when you're working with big hp on the street. |
"Hit everything but the water pump"... I laughed so hard the Coke i was drinking came out my nose.
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