Good primer by Car Craft for building a stroker....

http://www.carcraft.com/techarticles...y/viewall.html

 

This is excellent. I am going to up to 383 eventually, and am accumulating parts as $$ allow. Cuisinartvette (Ron) is working on my SLP runners and Edelbrock Hi-Flow base right now. I fell head over heels in love with your engine when I saw it; that's where I want to end up. I just want a 0-5000+ torque beast. With mega ported plenum, runners and base, along with AFR heads (not sure whether to go with 180's or 195's), 1.6 rockers and a good balanced 383 kit, I'm hoping to have some serious around town torque. Not sure what kind of HP I will end up with, but should make for some fun 'butt dyno' driving.
Many thanks for the article, Gregg. This is very helpful for guys like me who are still early in the learning phase.

 

Thanks and....

For a 383, you need to go for the 195's. The only reason not to would be if you're absolutely, 100% certain you'll always stay with a long-tube setup. Even then, the 195's allow for the use of a smaller cam (compared to 180's) and get the same result.

Just be aware of the "disease". Once you build something, you'll always wonder "what-if". You'll always be tempted to do more. That's where something like the choice between 180's and 195's makes the choice easier.

As someone once told me....The new 195 Eliminators flow as well as retro 210cc heads. But, they have the port velocity of their old 180cc lineup. Really, you get the best of both worlds -- especially with a stroked motor.

180's are a great choice when wanting to maximize low-end response with a 383....or even low-mid range response with a 350.

 

Only bummer with that 195 is I dont think his stock manifolds would cover the port. He could cheat with some Dyno Dons headers, or possibly some Dougs LT1s....hope they pass visual or swap them out every 2 yrs to test or just "pay". 180s they would fit right up. Might choke it a bit upstairs but...decisions decisions lol

Def feel that extra torque of the stroke though.

 

Wow thats an excellent article, thanks for posting Greg!

 

Your point about "the disease" is well taken. I'm not one to be constantly tearing my engine apart for the fun of it; I want to do this once, get it right, and not look back. I'm pretty certain that I will stay with the SLP's, given what I have invested in them and, frankly, I really like the looks of them. The primary reason that I was looking at the 180's was because I am under the impression that with 195's I would give up some low end torque and throttle response, which I would like to avoid. I would welcome your thoughts on this.

As Ron mentioned, there is a guy here in So Cal by the name of Dyno Don that is building shorty headers that are almost identical to the stock ones (thus possibly passing visual inspections), but have significantly larger port diameter. This may be a solution. Dealing with California smog issues is a real pain and adds a whole level of factors when making decisions.

Also.....
You said that the 195's allow for the use of a smaller cam (compared to
180's) and get the same result. This intrigues me because I understand that too much cam is one of the common causes of failure to pass CA smog. If I'm hearing you correctly, the 195's could get me the added power of a larger cam, without the smog and driveability issues of such. Is this simply because it is allowing more air/fuel into the cylinder, without the necessity for a bigger cam to hold the valves open longer?
I would be grateful for your thoughts on this as well.

 

I was thinking along the same lines. But, I ended up with a 383 that is WAY more responsive than the old 350 ever dreamed. In fact, it makes the LT4 seem sluggish. Please consider my recommendation to pick the 195's as something I did with the same goals you're currently thinking.

Ron knows a lot. We've talking many times and I enjoy his feedback and perspective. More importantly, Ron's in tune with your Cali requirements. (BTW...sorry I didn't notice your location before recommending the larger exhaust-ported 195's.) Even w/o DD's headers, Ron will be able to direct you to the 1 3/4" manifolds used by SlickFX. Or...maybe he knows if they didn't qualify for emissions?

Yes.

If it will pass smog (ask Ron), I think a hotcam or superram cam would work well. FWIW, it might be hard for inspectors to notice the single-pattern cam I used. And, 195's don't "need" any extra exhaust duration -- especially with a long-tube intake. OTOH, I like the sound of the hotcam better. It has a more distinctive sound. With a bit less lift, it might even be better for emissions.

FWIW, I think you would get 12-15 more HP using 195's vs 180s (and the same cam). I also think 180's vs 195's would be barely less NOTICABLE if you decide the manifold issue warrants them. Many builders say it takes 20hp to start noticing any appreciable difference.

 

I want to add a couple additional things to the excerpts of my prior post.

1) The biggest reason I picked the 195's vs the 180s was Lloyd Elliot's comment to me. He said he could equal the 180's performance, but the 195's were a superb head worth the money -- if you had it. Then he added that the 195's could not be paralleled w/o the aide of CNC porting. (IOW, hand porters can't touch them.) This said a lot about that head.

2) The 195's (IMO) are better for engines were you're able to [and want to] use a cam well north of .500" lift. On the simplest level, lift gets more power in a specific range while duration controls which rpms power is made. I wanted maximum power below 5k rpms. That meant leveraging as much lift as possible. (The problem you learn -- is where to draw the line between lift and valvetrain longevity.)

The later point [and your California emission's requirements) will determine your desired lift. If it turns out you want to use a cam with .525" lift or less, my recommendation to pick the 195's goes out the window. That's because the mid-lift numbers (and port velocity) of the 180's are better below .400" lift. For a cam with .500" lift, the AVERAGE lift will be below .400". So, IMO, it would be best to choose the 180's.

For motors where > .500" cams and/or >5000rpm powerband is desired, you should to look to 195cc or bigger heads. Most of the time, 383+ engine builders focus on this.

Lastly, if you look up Tony Mamo's last (big) thread to this forum, you will find a statement something to the effect: You should use the smallest intake runner possible to obtain your goals. The reason is it helps to maximize port velocity for optimum cylinder fillling.

So, while I was pleasantly surprised how will off-idle performance turned out with my AFR 195 Eliminators, I'm certain the 180's would be a bit better. For a street car, this can be important. AFR 180's should never be discounted as a viable option for a TPI longtube runner build.

This means I'd go with 180's and a hotcam --OR-- 195's and a superram cam. Make sense?

 

Yes; your explanations are clear and very helpful. My sincere thanks for your thoughtful time with this. BTW, you write very well.
Jeff