Thinking about switching back to NA, need help with a recipe.

96pushrod

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Can't argue with a dyno graph. That's about the same ratios as my Systemax 2. Which heads are you running?

Kurt
Some 205 11rs. The lower has a port match, but really nothing special with the combo. The cam is what some would consider smallish: 226/234 @.050 .576/.571. It is nice for driving though, especially in traffic.
 
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revhead347

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Some 205 11rs. The lower has a port match, but really nothing special with the combo. The cam is what some would consider smallish: 226/234 @.050 .576/.571. It is nice for driving though, especially in traffic.
My cam is very close to that. Custom grind with 112 lobe seperation. It also drives very nicely. I had a much larger cam in it before, but it really killed low end power, and drove terribly. To this day, my foot has a twitch when I drive. You kind of had to work it in and out like running an old sewing machine to get it to drive without bucking or surging. I am still on my old Canfield 192cc heads. That was what I was referring to with the "new stuff." I would love to have a set of 11Rs, I am sure they would put me in that ball park. I am still at 10.0/1 static compression ratio. Back in the day, that was as much as most engine builders were willing to throw at a pump gas engine.

On a side note, I got my shifter bezel in this morning. I obviously wasn't able to remelt the factory plastic tabs, but I attached the boot to the bezel with a thick layer of Ultra Black RTV, and it seemed to work out just fine.

Kurt
 

96pushrod

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My cam is very close to that. Custom grind with 112 lobe seperation. It also drives very nicely. I had a much larger cam in it before, but it really killed low end power, and drove terribly. To this day, my foot has a twitch when I drive. You kind of had to work it in and out like running an old sewing machine to get it to drive without bucking or surging. I am still on my old Canfield 192cc heads. That was what I was referring to with the "new stuff." I would love to have a set of 11Rs, I am sure they would put me in that ball park. I am still at 10.0/1 static compression ratio. Back in the day, that was as much as most engine builders were willing to throw at a pump gas engine.

On a side note, I got my shifter bezel in this morning. I obviously wasn't able to remelt the factory plastic tabs, but I attached the boot to the bezel with a thick layer of Ultra Black RTV, and it seemed to work out just fine.

Kurt
Nothing wrong with some Canfields. However, It is tough to beat some of the newer options when it comes to sbf heads nowadays. It’s crazy to think that you can get a badass set of cnc ported heads delivered to your door in a matter of days for less than $2000 - all with the latest and greatest valvetrain. That’s one thing I love about the 11r package, the spring and valve package is top notch. Essentially it’s ls stuff.

As far as compression, that’s essentially just free (kinda) horsepower. If you crunch numbers on my dynamic cr you would find that it’s scary high. It works for me though, no issues with detonation.

That’s great! I’ve got a bezel that just has the boot rtv’d as well. If rtv is good enough for planes, it’s good enough for me
 

revhead347

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Nothing wrong with some Canfields. However, It is tough to beat some of the newer options when it comes to sbf heads nowadays. It’s crazy to think that you can get a badass set of cnc ported heads delivered to your door in a matter of days for less than $2000 - all with the latest and greatest valvetrain. That’s one thing I love about the 11r package, the spring and valve package is top notch. Essentially it’s ls stuff.

As far as compression, that’s essentially just free (kinda) horsepower. If you crunch numbers on my dynamic cr you would find that it’s scary high. It works for me though, no issues with detonation.

That’s great! I’ve got a bezel that just has the boot rtv’d as well. If rtv is good enough for planes, it’s good enough for me
How high is your static compression? Valuable information for the OP. I think the best way to go is just to get a flat top piston and 0 deck the block. I actually have a dish piston to bring the compression down. Whatever the compression comes out to be with a flat top, grind the cam accordingly. I don't think running dome pistons on a street engine is a good idea. I agree on the 11R heads; it's a killer head package with the best stuff. My Canfields were $1600 hand ported back in 1999. That was the price I was able to get because I knew people. CNC heads had just come out, but only on the small TF 170cc, and Performer RPM heads. If you wanted a big head (which the Canfield was the biggest street head you could buy at the time), you had to get the work done. Every head needed a valve job out of the box. No idea why the factory valve jobs were so bad back then.

I don't care if the boot is just RTV'd on, as long as it clips down tight. Not worried about things I can't see.

Kurt
 

96pushrod

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How high is your static compression? Valuable information for the OP. I think the best way to go is just to get a flat top piston and 0 deck the block. I actually have a dish piston to bring the compression down. Whatever the compression comes out to be with a flat top, grind the cam accordingly. I don't think running dome pistons on a street engine is a good idea. I agree on the 11R heads; it's a killer head package with the best stuff. My Canfields were $1600 hand ported back in 1999. That was the price I was able to get because I knew people. CNC heads had just come out, but only on the small TF 170cc, and Performer RPM heads. If you wanted a big head (which the Canfield was the biggest street head you could buy at the time), you had to get the work done. Every head needed a valve job out of the box. No idea why the factory valve jobs were so bad back then.

I don't care if the boot is just RTV'd on, as long as it clips down tight. Not worried about things I can't see.

Kurt
Static is 10.8. Flat top and 0 deck is the way to go. You can run like 29* if timing with the 11r with flat tops for best power.
 

a91what

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The 11R head does not like alot of timing that is for sure, the chamber design is superb. we lost MPH advancing above 29* in the 1/4mile.
 

96pushrod

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The 11R head does not like alot of timing that is for sure, the chamber design is superb. we lost MPH advancing above 29* in the 1/4mile.
Yes, a very efficient chamber for sure. Really my only complaint about the heads is the don’t have the spread bolt hole pattern for headers. Besides that they’re great.
 

John Dirks Jr

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Get a 351 block and stroke it out to 408. That is a good place to start your NA setup. Then you can stay milder on the cam profiles and still make the power and TQ that you want. Actually, bigger cams will seem milder in a bigger cube engine too. An engine with gobs of mid range TQ and a less high strung attitude will last longer and be way more streetable.
 

a91what

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Thats what i am doing with my 393w, going to be running my blower cam in it for now. Heads flow 260cfm with a 224/236 575lift 114lsa... should drive and idle like stock and still make great power. I plan on dyno numbers NA before i get stupid
 

John Dirks Jr

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I think I got my 302 to just about the safe limit with 400 at the wheel with 10psi. I'd love to do a similar setup on a 351 block. I'm sure it would be 500+ and totally streetable and mild mannered.
 

revhead347

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You guys are misunderstanding airflow. The engine makes as much power as the heads will flow. If your 302 heads and blower make 400hp at the wheel, putting a 351 short block under all that will make 400hp to wheel at 500rpms lower, and that's it. Increasing the stroke will not substantially increase peak power, if at all. If anything, the added weight of the engine will only make the car slower. The stock 302 block is more limited by rpm than torque.

Kurt
 

John Dirks Jr

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I thought I understood that more cubic inches would be capable of ingesting more air. As long as you can match the increased air ingestion with the correct amount of fuel, that makes more power right?
 

John Dirks Jr

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Anyway, the longer stroke engines will make more tq at a lower rpm than the shorter stroke engines. And tq is what gets the mass moving down the track. Increase tq enough and you can use a higher ratio rear gear and still run the same time. And the higher ratio is much nicer for highway cruising.
 

Habu135

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Anyway, the longer stroke engines will make more tq at a lower rpm than the shorter stroke engines. And tq is what gets the mass moving down the track. Increase tq enough and you can use a higher ratio rear gear and still run the same time. And the higher ratio is much nicer for highway cruising.
I swapped out my 4:10 to a 3:73 in my stock block H/C/I 5 speed and it lowered the rpm at 80 mph some 500 rpms. Yuge improvement.
 

CarMichael Angelo

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Thats what i am doing with my 393w, going to be running my blower cam in it for now. Heads flow 260cfm with a 224/236 575lift 114lsa... should drive and idle like stock and still make great power. I plan on dyno numbers NA before i get stupid
A 114 lc n/a cam will be a pig. W/o a more traditional n/a grind to compare it to, you'll probably think that you're making decent power, but I'd bet comparitively that you're not.

If you're building a street motor for an N/A application, everything that revolves around that engine getting air in and out as efficiently as possible, All while being able to take full advantage of each power cycle w/o dumping part of it out the exhaust port. Anybody that thinks a cam optimized for forced induction is gonna work in a N/A application is kidding themselves.

It's gonna work, but not as good as one built for that purpose. Otherwise, we wouldn't need the Freezy's of the world...one cam should do it all.
 
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a91what

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A 114 lc n/a cam will be a pig. W/o a more traditional n/a grind to compare it to, you'll probably think that you're making decent power, but I'd bet comparitively that you're not.

If you're building a street motor for an N/A application, everything that revolves around that engine getting air in and out as efficiently as possible, All while being able to take full advantage of each power cycle w/o dumping part of it out the exhaust port. Anybody that thinks a cam optimized for forced induction is gonna work in a N/A application is kidding themselves.

It's gonna work, but not as good as one built for that purpose. Otherwise, we wouldn't need the Freezy's of the world...one cam should do it all.
The get stupid part is the turbo I have planned Mike. .. if I put together a combo with a NA cam then it wont be worth a :poo: with boost...