building a FAST legal small block

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AdamR

AdamR

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I would like to keep it pump gas friendly so under 10:1 ?
Cam, should I just go straight to a solid roller ?
It needs to sound stock so Im guessing 112 or 114lsa and maybe 220-230 @.50" tops ?

What about heads ? Im thinking a port job for this type of build is going to be a lot different then fir headers and single plane ?

What about the intake and exhaust manifolds ?

Im looking to be the fastest car out there but I would like to see some mid 12s.
 
I am assuming it will be a 360 based combo.With cams that small you would be better off with a good solid flat tappet.Why the pump gas ? You are giving up a substantial amount of power by limiting the compression.Stick or auto and what kind of RPM were you thinking ?What head did you have in mind ?
 
Monte, Welcome neighbor ! I grew up in Bethel.

Yes I'll be starting with a 360 block. Lower compression for pump gas because I would rather lose some power and still be able to drive it without needed to pump $7 a gallon in it. I just got rid of one of those motors.

Its a 4 speed with a low 3.09 1st and 355s. I would like to keep rpms down around 6000-6500 tops

Class rules require correct casting numbers which mean 915 heads.

My main concern is it has to look stock and be drivable, I just dont want a restored stock looking turd.
 
Adam,
WOW! theres so much you can do..............Think PRO STOCK and do the machining and then put parts where $$$ cant be seen. This is FAST(factory apearing street trim).
Some fast guys run 628 CI Heims so you'll need all you can get.
 
Rob 71, So it gets the thermoquad, electronic ignition, the good driver side exhaust manifold and the center dump passenger side manifold.

Bobby, Im not worried about catching the Hemi guys. Really my main concern is looking 100% stock on the out side but running much better and being streetable.

Even if I have to bend there rules a bit :wink:
 
So you want a FAST looking engine. Not exactly staying within the rules or......
Are you looking to compete? Or just do something like fast to make bigger spenders angry when you pop the hood?
 
Ive considered competing but how often would it happen really ? once or twice a year ?

If it fits the rules great but Im not really 100% stuck on following them.

In other words if it doesnt sound 100% stock I wont loose any sleep, I dont care what casting number is under the valve cover really (something they wont check until 11.80s anyways)

Other then that it will fit the rules.

It should look and sound stock. Rules call for bias plies but I may run some radials on the street.

Exhaust will be stock manifolds and 2.5" pipes with Dynomax Ultraflows and either an X or H pipe.
 
Bobby what Im looking for is suggestion on

Heads, As you know I have the 302 headswith 1.88 valves on the 360. Rules say I should be running 915s or that they atleast need to look stock from the out side and have a 915 casting number on them :wink:

Cam, again, needs to idle pretty smooth. I can use any cam, solid, Hyd or roller but with manifolds I need to be careful with what I run. Wide lsa ?

Stroke, I need a crank, should I step up to a stroker crank ? If I switch heads I'll take a huge hit in compression so I'll need a set of pistons anyways.
The stroker will be harder to launch especially with my low 1st gear but will be tons of fun on the street.

So in order of important.

Look and idle like stock 340
Be streetable
Blow the rear tires of on the street at will
be fast legal.
 
Heads, intake and exhaust manifolds are fixed by FAST class rules.

Your heads need to be the the stock heads for the year car you are building and casting numbers are checked. Mod them how you want but everything needs to fit under the stock valve covers.

Intake manifold needs to be the stock intake that would have have came on the engine (For you it would be the cast iron 1971, 340 intake.). Do what mods you want but casting numbers are checked.

Exhaust Manifolds must be the ones that would have came on the engine of that year. Do what mods you want but casting numbers are checked.

The carb needs to be the carb that would have came on the car. Do what mods you want but casting numbers are checked.

Your engine just needs to be a small block mopar of any year as long as it looks stock.

So....... If you want to run with the big boys in FAST class you will need to stroke it and push your compression out of the range of pump gas.

Or you could just be happy with 13s. It aint easy to launch the tires (Stock repop) that are required in FAST.
 
I was told by the judges casting numbers on heads/intake wont be checked till your in the high 11s.
 
I would suggest some GOOD pistons with a light ring pack.Depending on the whole package,400+ cubes should put you well over 500 ft lbs of torque,that could be a hand full to hook up at low speeds.Then you need enough cylinder head to feed it at 6,000 rpm to make it worth while.Do you want to run in the 11's ?
 
I am building something similar right now for a customer and should be done in a couple weeks.If the customer chooses he can post his dyno results when we are done.
 
Monte, I sent you a PM

I think at this point I should be more concern with it being drivable and fun on the street the track numbers. I dont want to end up with another car I dont want to drive any were other then cruise night. If Im going to spend the money I want to be able to enjoy it.

But I still want it to look stock and haul *** !
 
I think your best bet would be to build 415+cid engine, with a solid roller with at least .600"lift and lots of compression (12:1 or higher). Find a set of TA heads and go nuts with the porting. TA heads have the relocated pushrods and the 915 castings but i'm sure you knew that.
 
I have pondered a lot about a 66 D/Dart clone in the FAST class and if they would allow it. Think about it: The D/Darts had solid cams, headers, holley carbs right off the dealer floor. A 360 shortblock with some closed chamber 273 heads, although the heads would be a restriction I think. Traction would be a big issue. Oh well, just thinking out loud.
 
Adam, I know you have to nail down a bunch of stuff before thinking about the TQ but do you know if they will be checking #s on it? If not, see if you can sneak in a post-71 model in there due to the whole air vs fuel metered deal. Just wanted to mention this before I forgot.
 
Yes, I was told I can run a later carb and didnt need the one year only 71 carb.
 
AdamR said:
I was told by the judges casting numbers on heads/intake wont be checked till your in the high 11s.
Click to expand...

If you do what I think you will end up doing, you are going to be close. I really like the '71 intake as far as OEM cast iron manifolds go. The '71 exhaust is a big issue with me (probably the reason I haven't put the originals back on my '71 Cuda '340).

As far as the heads, I think you can do some pretty trick work there but again, those damn manifolds are going to be restrictive. I know I have brought this up before ... and I know it's expensive ... and I know the gain isn't huge but there is always extrude honing. Maybe you can find a shop that will sponsor that (unless there is something in the rules re: sponsorship).
 
71 A bodies only used the crappy passenger side manifold. The still have the good drivers side.
 
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