This piston any good. Meaning in the whole quench thingy I'm reading about. Is it enough. Just a daily driver with some eddy rpm heads. If not, what should I be looking for. What compression ratio would it give with 64cc head.
Those pistons are crap. I bought a set, and they're still on the shelf, collecting dust. I may use them as feet for a table I'm planning on building out of old engine parts. I'm kinda embarrased to admit I bought them though...
recommendations. please. Also can someone explain the quench/piston in the hole and how this affects cr. I really want to take a look at this with this build. That's just it.. my engine assembler would use these, this is why I asked. Please explain what I am looking at here with basically all stock components (rods/cranks etc). What is ideal. I am running an alum head too.
quench distance is your deck clearance and your gasket thickness, there is a volume there so it affects your compression. KB's are usually a good bet for a low priced piston with good quality. FT with 2VR is what I prefer, as lond as it doesn't send your compression up too high.
quench distance is your deck clearance and your gasket thickness, there is a volume there so it affects your compression. KB's are usually a good bet for a low priced piston with good quality. FT with 2VR is what I prefer, as lond as it doesn't send your compression up too high.
Any space taken out of the piston or combustion chamber should have more merit than "reducing compression" those deep as cast divots they label "valve reliefs" are often nothing more tahn a cheaper way to manufacture a "universal piston" with reduced compression. By increasing the quench surface and promoting better flame travle the increased compression is offset (to reduce detonation) and 2 VR's net you a hair more power. Only use the VR's you need. some pistons have 1 or none, but then you have to worry more about valve/piston interference. 2VR's are a great compromise. Also, as noted you need to pick your operating range first, then while considering other factors like your heads and displacement your camshaft, and finally match your compression to your cam, load (gear, weight, areodynamics), and fuel choice. Some people pick their compression first and then chase after a cam that will make it work, but going that route usually leads to unwanted compromises and suffering performance.
Many have said I could run 87 octane without a problem. I want compression, but not to the point where it becomes a problem for drivability.
I have an older hard block too that I am using (010/020 casting) I am still not sure to go cast or hyper. Is forged too much in the racing realm. I just want something that will last with this combo. Edelbrock RPM heads.
I wouldn't go higher than 9:1 with those tires and 87 octane in a truck. Even with aluminum heads those tires in a truck will be putting a lot of load on taht engine. Some people may advise 9.5:1, but I like a igiger safety cushion for trucks than I do cars, primarily because they load then engine more. And may carry a load from time to time.
This is comps cam. I have a local grinder that can grind me the exact duration @ .50-218-224, but the lifts are different. His intake/exhaust lift is 463/465. This cam is also on a 110. Seems like the Comp cam is more favorable on the exhaust side, but IS there a real big difference in performance here 465 lift on exhaust on my guys cam vs 469 ex. lift on the comp cam. I know this is basically the same cam, but what would be different with the head I am running. Sorry if asking a lot.. just really trying to dial this combo in.. and spend $$ once.
you won't notice a difference in performance. getting him to grind it would allow you to pick an LSA and an ICL which would have a far more noticable effect or performance.
I wouldn't go higher than 9:1 with those tires and 87 octane in a truck. Even with aluminum heads those tires in a truck will be putting a lot of load on taht engine. Some people may advise 9.5:1, but I like a igiger safety cushion for trucks than I do cars, primarily because they load then engine more. And may carry a load from time to time.
those heads don't need extra duration on the exhaust since they flow will on the exhaust side (unlike stock heads). In this case, use a cam with the same duration on both the intake and exhaust unless you are using stock exhaust manifolds. 110 lsa is good.
A compcam 260H with 9:1 cr would work nicely with 33 inch tall tires, 3.73 gear, stock converter, 4000 pounds, and 87 octane.
I am using Ram horns right now.. just can see putting those big ugly things nexto to pretty aluminum head, BUT if I have to use them to get started, you are stating to use a dual pattern cam rather than single pattern. Is that what you are suggesting. Otherwise, a single pattern cam with headers etc. I will look up the specs on the cam you listed.
I looked up the cam and it is a single patterns cam.. which suggest to me that you think the heads breath pretty good. What's the difference power wise in single/dual patten cams. Also, how does the duration part work now with them both being 212. Is this just an open duration cam. Forgive me.. I am learning.
Yes, the cam is on the smaller side. It will idle smooth. maybe a little lope from the exhaust if the idle drops below 700 rpm
the cam has 260 degrees advertised (at 0.005" lift) and 212 degrees at 0.050". with the exhaust the same as the intake. you should run headers if you are needing more power. exhaust manifold are nice for quiet exhaust and no leaks. I prefer exhaust manifolds in my old age.
since this is going into a truck and has 33 inch tall tires, you need a torquey cam. the 3.73 gears help, but the tall tires knock that down to around a 3.42 gear. Plus the cam works well with a stock converter. Any bigger on the cam, then I would go with a higher stall.
and as always, use zddp oil additive with your new cam.
Gotcha, so I am at the limit to where I'll have to add an additional performance part (stall). This is about where I wanted to be. The cam sounds good for what I am wanting.. but do you think heads will breathe too easilynow or is this what you want. I am after mpg as well. I could be wrong, but doesn't TORQUE, no matter how you get it save mpg. Will take less power to move same distance?
Someone told me single pattern cams make more power, I have also heard the opposite.
Then this is not the torque I want. Can you explain your ideal set-up with my given components.. and or how I get the torque working for me instead of against me. But I thought that's what torque was still? Slightly confused.
Also, why isn't it all that simple with the given components I am working with. After all, these are all the pieces that need to be taken into consideration when selecting a cam. Are you trying to say 383.
Also, why isn't it all that simple with the given components I am working with. After all, these are all the pieces that need to be taken into consideration when selecting a cam. Are you trying to say 383.
We're trying to say taht when driving a big box (truck) you cannot get great gas milage with a carb and a non OD trans, especially with big tires. You will not get above 15 MPG no matter how hard you try. If you want milage drive a gocart.
Just something else I found looking into single vs dual pattern cams.
You also asked for cam input. I think you need to make a cylinder head decision first. Here's why. The AFRs flow VERY well on the Exhaust side, producing a very high E/I flow ratio. They work very well with single pattern cams. Just about any other Chevy head works best with a dual pattern cam (that's why so many Chevy cams are dual pattern . . . . . ) Using the AFR heads, and looking for a particular type idle quality and performance curve, you can increase the Intake side's duration some (as well as the exhaust's) and still maintian the same overlap and LSA you'd have with a smaller intake lobe on a dual pattern cam. Is that confusing?? It sounds confusing to me. Think of it this way. Overlap has a lot to do with idle quality. Overlap is a function of LSA and the sum of the Intake and Exhaust durations. So, if you use a single pattern (reduced Exhaust duration) cam you can take some of that exhaust duration that you didn't use and apply it to the intake side. Thus, you get a longer intake event. And an adequate Exhaust event. An exhaust event that might not have been adequate had you had a poorer flowing exhaust port. When purchasing a cam, this is good to know, because some companies will custom grind a cam (using their standard lobes, but with custom lobe combinations and custom lobe orientation) for you. Some will even do it for free. So, you can get just exactly what you want. I bought a Comp Hydraulic Roller for my 383 a few years ago. I ordered single pattern (two identical lobes) because I'm using AFR heads. So, I was able to slightly increase the intake duration, and select the LSA I wanted. Have fun!!
Go to the Iskendarian Cams (Isky)website and read the tech tips and engine myths section. It will answer almost all of your questions (the dual pattern vs single pattern cam debate), and it is very interesting reading.
Torque or more torque is not free. The "torque" That you are refering to is made by burning fuel.
High gas mileage is all about using the least amount of fuel for the job.
Everything you "heard" is 99% not true or taken out of context.
Then this is not the torque I want. Can you explain your ideal set-up with my given components.. and or how I get the torque working for me instead of against me. But I thought that's what torque was still? Slightly confused.
Torque is twisting force. Horsepower is a function of torque. HP = peak torque X the rpm the peak occurs and divided by 5252. The higher in the rpm band where peak torque is made will have more horsepower. A cam dictates where the engines power band will be. A short or small cam make torque down low in the rpm along with a nice idle and good vacuum. A big cam pushes that torque peak up in the rpms sacrificing it in the low end along with choppy idle and lower vacuum. Heavy vehicles need more grunt to get them moving so low end torque is needed.
Torque is twisting force. Horsepower is a function of torque. HP = peak torque X the rpm the peak occurs and divided by 5252. The higher in the rpm band where peak torque is made will have more horsepower. A cam dictates where the engines power band will be. A short or small cam make torque down low in the rpm along with a nice idle and good vacuum. A big cam pushes that torque peak up in the rpms sacrificing it in the low end along with choppy idle and lower vacuum. Heavy vehicles need more grunt to get them moving so low end torque is needed.
"nice idle" meanign smooth here. And while a small cam will give you more low end rear wheel torque, a gear change will also give you more rear wheel torque... Something else to consider.
For milage you're best off with a small cam, small runner volume, dual plane, cvacuum secondaries, etc.
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