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Discussion Starter #1
hey guys I am thinking of rebuilding my 351c. The guy who had the car before me put in a kragen rebuilt and I don't think it has much compression. I figre it's like 8.5 to 1 or something around that. Well I just had the 4v heads redone a year ago so all I need to do is the short block. I really want to build a stroker, but don't have the money for a kit. Can I use something like a 400m crank and different rods to make a stroker? or should I just stick with the 351c and put higher compression. It's mainly for the street but also occasional strip action. Another question is I have 4v heads how do I tell if they are open chambers or closed? And my final question is what is a good cam for the street, I want lopy but not rattle my teeth lopy. Thanks for you help
 

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Open chamber is just that. Almost circular chamber in the head. The quenched chamber is almost kidney shaped. That's about as good as I can discribe it for you. Maybe some one else can do a better discription.
 

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There is a good pic of Quench heads on my site ... Second page "The Beast". take a look. Access from my Home Page.

In fact my entire build is documented on the site ... Complete parts list and narratives on the build ...

If Desk Top Dyno estimates of 537 HP and 479 FT LB are "Killer" enough for you ... you could do your build right from the list I have provided


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Larry Madsen
Las Vegas Nevada



<font size=-1>[ This Message was edited by: monstermach on 2/16/02 8:32am ]</font>
 

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Discussion Starter #7
Nevermind I found it, your engine is pretty bad ass I wish I could afford it. Thanks for the info.
 

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On 2002-02-15 20:22, MonsterMach wrote:
If Desk Top Dyno estimates of 537 HP and 479 FT LB are "Killer" enough for you ... you could do your build right from the list I have provided

<font size=-1>[ This Message was edited by: monstermach on 2/16/02 8:32am ]</font>
Desk Top Dyno's horsepower and torque estimates on engines using 429CJ or 4V Cleveland heads are way off. The reason is that Desktop Dyno doesn't ask for actual port volumes or port area, instead they estimate the port area. Since Cleveland 4V's are so unique with thier ports being so huge, the ports are bigger and the airflow velocities are far less that Desktop predicts. Therefore Desktops torque numbers tend to be quite inflated and thier cam timing and flow velocity relationship is way off as well. If you want to get an accurate computer dyno simulations on engines with ports like that, you have to use a program that specifically asks for intake runner dimensions.
 

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as far as I know, the only way to check if they are open or closed is with the head off. Look inside the chamber whare the valves are, the open chamber head is somewhat bored out (concaved),

the closed chamber is flater, more to the surface to the head, makeing more combustion.

like coupe3w had said, the circular (open) is hallowd out, and the closed (quench) is filled in.

There were some posts about 4 months ago with pictures and a ton of responces. good luck finding them!!!!

as far as stroker???
i dun no.

I just had mine built, and the cam is an RV, i'm not real sure how to read the specs on it, but it seems a bit mellow. My builder recamended this cam because I have an automatic and it wouldn't idle for ****.
I just put on Holly 750, on top of an edelebrock performer, but it only gives me 5500 rpm then it starves. I'll be changing it soon.

what I have in my rig is;
351C 4bolt mains
4v closed chamber
bore .030 over
Keith Black flat tops
RV cam
MSD 6A, Mallory dist.
Holly 750, Performer intake
headers, 2.25" duals straight back

with the exception of the intake, I like what I got. for my light '56 f-100 it moves.
 

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Under the heading of "For what it's worth."

In reference to my Engine "The Beast" ... I always openly state that the power info I have is from "Desk Top Dyno." At this time it's the only power estimate info I have.

I don't profess to know a lot about these programs ... Anyone that cares to run the thing through any other program and figure out (what you may believe to be) more accurate figures is absolutely free to do so.

All I can tell you for sure is ... This is one Nasty A$$ ride ... If it had more power than it has ... I wouldn't know what to do with it.

No effort on my part to misrepresent anything The entire build is documented on the internet ... right down to the shop rags.


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Larry Madsen
Las Vegas Nevada



<font size=-1>[ This Message was edited by: monstermach on 2/17/02 1:49am ]</font>
 

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....Desktop Dyno doesn't ask for actual port volumes or port area, instead they estimate the port area.....
Dyno 2000 3.08 allows input of exact headflow data .. Can set it at up to 10 data points and enter the exact figures from your headflow .. providing you had your heads flowed .. If not, several net source for Stock Flows you can use as input .. or use the built in flows on the Dyno ..

Versatility in Desktop Dyno is there, but for near accurate results... you need accurate input ..

-dc
 

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On 2002-02-16 19:13, 1993Bolt wrote:
Dyno 2000 3.08 allows input of exact headflow data .. Can set it at up to 10 data points and enter the exact figures from your headflow .. providing you had your heads flowed .. If not, several net source for Stock Flows you can use as input .. or use the built in flows on the Dyno ..
That's my point. Entering flow data is not enough by itself. To be accurate the program has to also have an input for port area. If you build two engines with heads that have similar head flow numbers, but each engine has different runner sizes, the engine with the heads that have the smaller runners and higher velocity will make far more torque and power and the torque and peak power will both arrive sooner in the powerband. Or to put it another perhaps simpler way. A 185cc intake port that flows 280 cfm can make much more power than a 230cc head that flows 280 cfm. It's because of port velocity and the fact that it will be far higher in the head with the smaller runners.
 
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