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Old 12-22-2010, 05:08 PM   #1
JW76
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355 engine combination

I have a 350 bored .30 over with flat top l2256f30 pistons with 4 valve reliefs. The cam is CL12-326-4. Basic Operating RPM Range is 2,200-6,200.
It is a single pattern 490 490 lift 236 236 duration @ .050 with LSA of 110.
For heads I have a set of world s/r torquers 200cc 2.02 1.60 with 72cc chambers. I have a steel shim headgasket to get 9.75:1 compression and keep quench around .038. My intake is a weiand dual plane 1,500-6,200 with holley 650 double pumper. The tranny is a th400 with reverse shift pattern manual valve body and 2800 stall converter - rear is 3.73 posi

should it go good?

Thanks
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Old 12-22-2010, 05:33 PM   #2
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Re: 355 engine combination

Its a street vehicle that may see a little track time or have come fun corner carving. I realize it may not be the ideal combination but curious.
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Old 12-24-2010, 03:56 AM   #3
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Re: 355 engine combination

Throw on some sticky tires and it'll make a huge difference. I'm no performance expert, but it looks like it'll do fine. There was a guy down here in Texas running in the 12's/13's with a similar combo(cam and carb were bigger).
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Old 12-24-2010, 11:56 AM   #4
Marv D
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Re: 355 engine combination

Sounds pretty decent to me, except for the heads. The 200cc torquers are more intended for a 400+" street motor, OR a high rpm, BIG cam, high compression smaller motor (i.e. like a 302- 327 launching at 6000 shifting at 8500,) Case in point,, the 2.02 intake valve and a 200cc port is a mismatch in my eyes. Most 195+cc ports are sporting a 2.08+ inch valve. Why did world choose to choke them at the valve with a 2.2?? beats me. Obviously I'm not a big fan of the torquers but they do make for a nice street combination. I just feel the smaller cc intake port would have been a better choice for the rest of the combination listed and going in a heavy truck.

Will it 'go'?? YES, Oh YES it will be a very decent combination I think. But I think your going to run out of cam before you run out of potential in the rest of the combination. What I mean,, it is very likely going to nose over around 6000, but I've taken many many a 355's into the 7000rpm range with stock internals and forged pistons and they survive extremely well. I think your going to find the motor will pull well to 6000, then flat line,,, But at the track if you spin it up more (6800+) you find the ET improves.

Getting those heads working is going to take RPMs from a 355, getting your 'after the shift' rpm's up in the meat of the torque curve will show if I'm right or wrong.

See if you can get Super73 to model the engine in Engine Analyzer and show you the torque curve. Then there are a lot of 'after the shift' calculators on the net to put as much torque under the curve as possible. Play with it and see what I'm talking about.

here's one of the better pages I know of with shift calculator and a BUNCH of other stuff.
http://www.bgsoflex.com/auto.html
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Old 12-24-2010, 04:07 PM   #5
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Re: 355 engine combination

Honestly, I wouldn't go any bigger on the cam. Thats already a fairly decent sized cam for a street motor without huge compression
Yes, the heads would work better with the higher RPMs. But, its still a big heavy truck, with tall tires; you'll want the low end power. You'll have to sacrifice a bit on the low end to make more on the top end.
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Old 12-24-2010, 04:43 PM   #6
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Re: 355 engine combination

Thanks for the input guys. Really appreciate it!

The heads came about because they were a great deal. I know they're not optimal but I scored them assembled brand new for 300 dollars. Im hoping it all works out pretty good. I just finished converting the truck to trailing arms. Its a longbed 86. So I hope it handles good and runs good.
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