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Author Topic:   434, anyone run one ?
Kromulous
Member
posted October 28, 2004 08:55 AM
Anyone running a 434 in a mod out there, could you tell me how you like it?

Were contemplating building a torque motor, low rpms and decent HP, but very high torque. It will be a flat tapper, iron eagle 49cc 215cc runners, and flat tops (forged). May mill the head for more compression 13.5 to 1 is our mark we want. 4340 crank 52lbs, and some I-beam rods.

Anyone run something like this?

zeroracing
Member
posted October 28, 2004 10:46 AM
if you want 13.5 to 1 then you need different heads. with the 49cc head your gonna have about 14.8 to 1 with flat tops. your gonna need about a 55cc head assuming your zero decked with .041 head gaskets and -5cc flat tops.

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Kromulous
Member
posted October 28, 2004 12:06 PM
Blows apart the mains due to the high torque? of the 434 combo. I was worried about this, might have to bite the bullet and buy a Dart little M, i guess.

I havnt sat down and done the math on the compression, but most generally we dont like running zero deck blocks. I usually like the .003 to .005 in the hole.

If that doenst do it, we can run a small dish piston, they make abit more power anyway. Maybe a -12cc or so.

I'll sit down and figure it out tonight to be sure, i'm just kinda brain storming ideas on a 2nd motor right now really.

dennie
Member
posted October 28, 2004 02:24 PM
seems like the popular late model/modified setup is a big bore short stroke combo like a 377 to 393 ci range motor. maybe that would work better if you race on smaller tracks.

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Racer111
Member
posted October 28, 2004 04:20 PM
Ran a 434, real easy to hook up.Use a displayed cap block.Stroker rods like lunati pro mod rod,saves a ton of block grinding.Turned engine 7200 with a eagle crank,Ran perfect sold it .A couple hands later a guy turned it 8000 broke the crank right in half.Its easy to hook up because the TQ is smooth.The trick to a 430 is the cam your .050 numbers will be high.Its a good engine just dont turn it 8000.


rocket36
Member
posted October 28, 2004 10:16 PM
not sure you can get 434 out of a gm factory block. i think you may only be able to go to 421 unless you use an after market block like world or dart.


Kromulous
Member
posted October 29, 2004 07:43 AM
Most guys where we race like the 415, and 420's. Running right at 700 HP (UMP rules), they run well.

I talked to a couple of guys about a 434 and they all said there smooth as long as you dont get to radical with the cam and keep the runner sizes on the heads down in size.

My plan is to use a steel head, and flat tapper cam so its legal for other sanctions than UMP. So if we run a show somewhere else, we can be legal.

Racer111, why did you sell it, and would you run another one if you could? and was it built around a stk chevy blk ?

Thanks for all the good info so far, Krom.

Racer111
Member
posted October 29, 2004 06:43 PM
Ran stock block displayed caps and block fill barly above block drain plugs.Use the stroker rods from lunati.A 420 is better less stroke on crank will rev a little faster.Same power easyier on the crank.If i was running IMCA it would be a 420.Sold it and went to a 18 degree 410.


Kromulous
Member
posted November 01, 2004 07:19 AM
Ok, sounds like the 420 is the better choice. We dont want a time bomb on our hands, that costs to much.


DPORT60
Member
posted November 07, 2004 08:08 PM
Also with the 420 or 430 get a Canton pan there built for stroker engines.


paulickr
Member
posted November 11, 2004 04:35 AM
i would like more information on what combination of parts i will need to build one , can you e mail me the info. rpm20@earthlink.net thanks ron


quote:
Originally posted by Istock66:
You can build a stock rod 434 without touching the block in many cases with a grinder..

The pan deffinitely doesnt need touching with stock rods.. all that work is for capscrew rods..