12 Second N/A Slant 6?

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If you want quench I'll go with custom pistons with a quench pad instead of heavy milling and welding, that's my plan if I put J heads on my 273.
 
Using KB168 2.2L Turbo pistons on an offset ground crank. +.070" deck on the block.

.055" quench.

You seem to have examined every aspect of this project with a magnifying glass and have a GOOD answer for everything.

It's a well thought out exercise, and impressive in its thoroughness.

Which leads me to wonder how you come to be using "turbo" pistons in a normally-aspirated engine.

I have no knowledge of these pistons, but I think that in all probability, pistons designed for a "forced-induction," OEM application, would likely be forged, and if so, probably might be significantly heavier than pistons designed for no boost.

Maybe that's not true in this case, but it made me wonder.

As you undoubtedly know, normally-aspirated (OEM) engines, usually utilize cast pistons because they don't need the strength of a forging, and I am assuming that these turbo pistons are forged, which may be a mistake on my part.

Maybe you could explain how these came to be the piston of choice in an engine wherein a light-as-feasible reciprocating assembly would seem to be really important.

Thanks for any information!!!

Good luck with your project.
 
Which leads me to wonder how you come to be using "turbo" pistons in a normally-aspirated engine.

I have no knowledge of these pistons, but I think that in all probability, pistons designed for a "forced-induction," OEM application, would likely be forged, and if so, probably might be significantly heavier than pistons designed for no boost.

Maybe that's not true in this case, but it made me wonder.

As you undoubtedly know, normally-aspirated (OEM) engines, usually utilize cast pistons because they don't need the strength of a forging, and I am assuming that these turbo pistons are forged, which may be a mistake on my part.

Maybe you could explain how these came to be the piston of choice in an engine wherein a light-as-feasible reciprocating assembly would seem to be really important.

Thanks for any information!!!

Good luck with your project.

I have utilized "turbo" pistons for the 18cc cup in the crown. The pistons in question are "hypereutectic" cast psitons. They are very strong W/less expansion ratio than forged. That allows running close tolerances on the piston skirt clearance & a longer lasting engine build.

Forced induction engines ususlly utilize low CR in the 8:1 range to allow more room for the compressed air. Think of 2 identical air compressors. One has a 40 gallon tank, the other a 50 gallon tank. Which compressor can store more atmosperic pressure air when it is compressed to a given pressure? The larger volume combustion chamber serves the same purpose.

When the 2.2L turbo piston is utilized in an engine W/4.175 stroke, the designed 8:1ish CR of the original application climbs to the 12:1 CR range.

Indeed I will need to add about 10cc to that cup volume if I am to run 93 octane pump gas.

At 1st I thougt this was feasable but closer examination to the drawing @ the beginning of this thread makes me think otherwise. The cup is flat on the bottom so there is no material left to remove from the already minimal thickness crown. At best I might gain 1 or 2cc, not the 10cc neccessary.

I can not increase the already maginal quench distance to lower CR as that will increase the likelyhood of detonation even though CR is decreased.

It may be neccessary to explore water methanol injection. At 1st I was not able to wrap my mind around how one would control the W/M injection W/O complex plumbing & switches.

Since I have many of the components on hand from a failed attempt to use W/M injection on my '06 Charger 5.7 Hemi, I did not want to spend over $600 for a "kit" that would contain at most $300 worth of compnents, many of wich I already had.

When it looked like W/M was going to be mandatory I expanded my search & found this controler than works on both vacuum & RPM.







http://www.alcoholinjectionsystems....thanol-Injection-Controller/product_info.html

The controller will take care of WM injection during high load conditions, but what about low load & idle?

I found an article about using a large hypodermic needle tip inserted into a carburetor vacuum circuit. This article was concerned primarily W/the fuel economy savings but it will serve our purposes here for spark knock suppression.

Now, since we are no longer limited to 10:1 CR I am thinking along the lines of decreasing the quench hieght to a more desirable .040". That will jump CR up into the 13:1 range.

All of this is speculation until I get some head casting to work with.

If the stock castings will allow a realistic shot @ a 10:1 CR then that is the direction I will go. If not, then quench distance will be optimized to .040" & WM injection will be utilized.

If WM dioesn't work, there's a small airport near me that has high octane aviation fuel as well as 110 octane race fuel @ another source.

I think that I can make WM work. If I can, a 13:1 \6 utilizing WM injection should be able to make in the neighborhood of 300HP.

EDIT: Here is the article on the vacume W/M set-up for low load conditions.

http://www.dave-cushman.net/misc/mannject.html
 
This is a very cool project and I thank you for posting it. I will defenantly be following this thread. Good luck, I hope it all works out for you!
 
Don't expect this to be finished soon.

This summer will be devoted to getting the Valiant on front discs W/an 8 3/4" in the back.

I'l be gathering engine components through the summer for a winter ebgine build.

There will be updates as componennts are aquired & things checked out.

First thing that needs to happen as far as the engine build is getting some cylinder heads to check the combustion chamber geometry.

It all hinges on that as far as which way we go.
 
I ran this setup through my dynosim5 but its stock stroke 10:1, 500cfm carb, headers, 282cam and RustyRatRod's head flow numbers 270HP@5500 and 281ft-lb@4500
 

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That's promising. Wanna play some more? I picked out the cam I am gonna run with that head.

.539/.537 254/267 @ .050 ground on a 112 and my compression will be probably 10.5 and I'll be runnin an 800 TQ.

..and yes, the lift is a reverse grind.
 
RustyRatRod i put your CR carb and cam 274HP@6000 273ft-lb@4500 yours takes off after 5500 vs the orignal one i did with comp cam 20-231-4 specs.

P.S. does anyone know how to make the pic larger?
 

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Yup the torque drop is the 112 LSA. I may rethink that and do a 108 or 106. That's enough torque to try and regain.
 
See what one more will do for me if you don't mind.

.489/.489 230 @ .050 ground on a 105 Solid of course. Thank you drive through.
 
260hp@5500 289ft-lb@4000 your new cam is the torque king of the 3 but gives up a little hp above 5000, to me it looks like a good trade off.
 

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Wanna try one more thing? Take that big cam and narrow it down to a 106 LSA and see what happens.
 
How about cooking up some HP/TQ numbers for this combo.

241 cu in, 3.505" X 4 175" B/S

12.5:1 Static CR

Same heads

Clifford 95-122 262° @ .050" .595" lift W/1.6 RAR 109° ICL, 109° LSA.
 
Who are you gonna get to port your head? I can highly recommend Jerry Killian from first hand experience.

How about cooking up some HP/TQ numbers for this combo.

241 cu in, 3.505" X 4 175" B/S

12.5:1 Static CR

Same heads

Clifford 95-122 262° @ .050" .595" lift W/1.6 RAR 109° ICL, 109° LSA.
 
That's onewildandcrazyguy. He's a dang goodun too. Really sharp.
 
I'm think about using 7mm stem metric valves.

I want to stay away from the long stems on the 318 valves & the rocker arm geometry changes involved.
 
RustyRatRod i did 112,110,108,106 on the bigger cam but it loses power all over the place as you go down from 112 to 106 especially on the edges of the powerband also did 105 vs 110 on the smaller cam 110 had a little more bottom end and 105 had a little more top end. My program can go through 1000 of cam specs, you have 4 choices of what it will search for peak horsepower or torque, or average horsepower or torque between certain rpm
 

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