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Luke805

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I am considering building my current 350,and I would like to build it to produce a lot of HP/Torque,but try and do it efficiently and keep it streetable since it will be my daily driver. I'm leaning towards going with some AFRs for this motor. I'd appreciate suggestions on different 350 combos.Any desktop dyno builds would be great too,thanks.
 
Sure!

Just build your engine for max torque at 4000 to 4500rpm by using either a CC 268HE duration hydraulic cam, or a CC 282S solid cam.

CR. should be about 9.5 to 1 for pump gas use. But can be higher with aluminum heads Tight quench of .035" and slightly above to say .045".
Use 180 cc, 2.02"/1.60" heads.
A set of 1.625" four tube, long headers. Either an E/b RPM, Weiand 8004 or Stealth, or a Holley 300-36 dual plane intake and a tried and true, tuned for your engine size, 3310-2 vacuum secondary Holley four barrel carb.!

This should net you, figured with open exhaust, slightly above 370 hp at 5500rpm and slightly above 410t at 4000rpm with the 268 cam!

And right at 415 hp at 5500rpm and the same for t at 4500rpm with the solid cam!

You might need/like a stick with the solid cam and at least a set of 3.31 to 3.55 rear gears along with about 25.5" tall tires!

I personally like rowing the gears! Hope this helps. pdq67

PS., and it is well worth the money spent to buy a copy of D2K, Drag and the cam file to help see trends in engine combinations as you change parts and then run simulations down the quarter to test each combination!
 
Not much to add to pdq except for hydroller. I will allow much more lift in a similar duration and will add torque. If use afr go for the 180 head.

[This message has been edited by 89rs400 (edited 06-06-2002).]
 
Luke,
You're getting some excellent advice from these guys. For a very streetable 350, you should aim for peak horsepower at 5500RPM and use a 3.55 gear. This puts you at the start of the midrange at cruise and makes the car responsive and fun to drive.

Upgraded heads, roller cam and high performance dual plane intake will put some radicalness and horsepower potential into the motor, and then you can take it back out with slightly subdued cam timing. Stay away from too early intake opening. Aim for 375HP at 5500.

You can also do some minor blending on the heads you have, and then flow them. If you can get the exhaust to flow at least 72% of the intake you'll be in good shape. Otherwise go to the next larger exhaust valve size if you can. Once you have the flow numbers, pick the shortest cam that will give you peak power of about 330-350HP at 5500RPM with about 9.5 to 1 compression on premium. The hydraulic flat tappet cam will be something like 222degrees intake at 107ILCA, and 232degrees exhaust at 117ELCA. This is longer than the roller cam needed for the 375HP engine described above.

You'll want to upgrade your intake, but don't exceed the head's port size. Your 600CFM carb will suffice. Use the 3.55 gear. Headers will be 1 5/8 by 36", with a 2 1/2" by 14" collector to the crossover. Use 2 1/2" exhaust. This is the cheapest way to upgrade performance, but maybe not the most fun. A workbench loaded down with new parts is the most fun if you have the money.

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Rodney Davis
HeaderDesign.com
 
My 350 build up is pretty close to your recomendations except the rear gears. Until I can afford the swap, I'll be using 3.08 open and I have an M20. I'm curious. What is the affect going to be?
 
CHP magazine did a build awhile back that was a great looking street motor.

The short block was standard 350 with a .030'' overbore, with pistons yeilding 9:1 compression. They stuck in Comp Cams XE268 grind hydraulic flat tappet cam, and topped it all off with a pair of AFR's new 180cc runner heads and an Edelbrock Performer RPM intake and a 750cfm carb.

This pulled plenty of vacuum, idled very well, and made 415 horses @ 6000rpm and 435 ft. lbs. of torque @ 4000rpm. It also made 400+ ft. lbs. from 2900-5400rpm. Very stout and very streetable!

The info given above is also very good.
 
<BLOCKQUOTE>quote:</font><HR>Originally posted by Winch:
My 350 build up is pretty close to your recomendations except the rear gears. Until I can afford the swap, I'll be using 3.08 open and I have an M20. I'm curious. What is the affect going to be?<HR></BLOCKQUOTE>

The M20 has a good 1st gear but the gear spacing is too wide. Especially on the 3/4 shift. Go with a mild cam and small port size to keep velocity up after the shift point. XE268 is ok.. keep weight as light as possible.
 
Winch,
Your 3.08 gear will leave you down on torque at cruise if your engine horsepower peaks at 5500. Try to gear it to "heavy cruise" at 60% of the peak horsepower RPM. The exception is if you have great heads and a conservative cam, then 50-55% is OK, but your headers and intake won't be working for you. I like 60% so I have power underfoot all the time, and the header's scavenging wave is there to battle the intake manifold vacuum during the overlap period. Economy can be surprisingly good.

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Rodney Davis
HeaderDesign.com
 
Thanks for the replies, I just wish I understood what you just said! This is all greek to me. My engine is set (for now anyway) with: 10:1 flat tops, TFS heads, CC 282S, 1 3/4 Hedman headers, Performer Rpm intake and 750 carb. I plan to eventually go to either 3.73 or 4.11 gears. I just don't know what to expect until then. Will I have to slip the clutch more, rev it out further before shifting, etc.
BTW until the rear gets done (which will include new springs and SFCs) I'm going to try to keep my foot out of it, especially no clutch dumps. I can only imagine what I'd do to that poor old rear if I try to light em up.
 
Winch,

Your car should run great with a 3.73 or 4.11 gear. I was thinking your car was a daily driver type, so ignore what I said above. Use the gear that will give lowest ET's. The 3.08 gear may make the car surge in first gear, and you probably won't be using forth gear too much. You're going to get something like 400HP at 5900RPM, so a good highway cruise would be (60%)*5900RPM=3540RPM. The 4.11's will give this.

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Rodney Davis
HeaderDesign.com

[This message has been edited by Need a Camaro (edited 06-07-2002).]
 
Hey! 3500 rpm is not a good highway cruise!Not to mention it sucks the gas. The day of the M-22 and a deep set of gears are over. I just got rid of my 3.90s and couldnt be happier. Now I don't have to drive in the slow lane anymore! Street driving is more than just stoplight to stoplight. A 5 or 6 speed tranny with a 1st gear, 3.00 or so, is the way to go. Keep the 3.08s!

John
 
John,
What are you doing driving in the slow lane? You shouldn't be telling us that. I'd be interested to know what your engine specs are.
Winch's engine is going to run plenty soggy in the mid 2000's. Gas mileage won't be too good down there. I like to feel the torque of the engine using the seat-of-the-pants method. Put the car in second or third and accelerate from off-idle through the midrange. When a powerful car first starts to jump up in the midrange, look down and note the RPM. That's where you should center your highway cruise RPM. I cruise all day long at 3000RPM with a lesser engine than winch's. Runs great and I get 17mpg with the headers.

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Rodney Davis
HeaderDesign.com
 
My combo is very close to what Winch has but with 10-1 comp. edelbrock rpm heads, 600 dbl pump, cam is 232 @.050 .488 108 LSA. 1 5/8 headers. I has a 3.08 rear gear with posi. I have decided to go with a Richmond 5 speed with a 3.27 first gear. The average speed on highway 5 here in Oregon, is 75-85 mph. Could'nt keep up with traffic with the 3.90s and the short 25 inch tire. Not for long anyway.

John
 
Not everyone can afford the nice new 5/6 speed trannies out there though. I personally have 3.73 gears out back, and wish I had 4.11's most of the time. I seriously doubt he takes the freeway to school.

And Winch, lighting up the tires isn't really rough on your rear end. It's when they hook that stock parts can get unhappy.
Image


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79' Z28 4-spd - daily driver
 
John,
Sounds like a good setup for your engine/tires and 75-85mph. You should be cruising in the low 3000's there, when your engine is just starting to jump up on the torque curve. If you have the 1.23 forth gear you'll also be in great shape for 55mph cruising. I wonder what transmission ratios Winch has.

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Rodney Davis
HeaderDesign.com

[This message has been edited by Need a Camaro (edited 06-08-2002).]
 
I agree that I will have to save for quite awhile for the 5 speed. A super T-10 with a 2.88 first gear looks good too. It will have some RPM drop between gears, but I think it will work OK. Lots of people drive on the highways nowdays and thats why I made the comment. Just what I've learned with my cars. People are different, some can deal with 3500 rpms on the highway, I can't anymore. Back in high school, I ran a 55 chevy, with a 5.38 gear behind a 292 small block, with #186 fuelies, edelbrock scorpion intake, sig erson, solid cam. shifted at 7500. That was my daily driver. It was lots of fun!

John
 
Hey Rod, I know what you mean about that curve! my 61 chevy was geared that way with 4.10s, was running a TH400, never needed to hook up the passing gear switch. It didnt need it. Just step on it in third. It would pull to 100+ real quick! I think Winch has a M-20. ratios 2.52, 1.91. 1.46, 1.0 I think!

John
 
I know I have an M20. I think those ratios are right. This car won't see much highway use if any. Just cruisin' and the occasional 1/4 mile. I have no idea what kind of use the kid will have for it. He's only 11 now anyway. I'm just planning on having something really cool that he'd want bad enough to keep his grades up and his nose clean if you know what I mean. And something for us to do together. I'm sure I'll have the gears chnaged by then.
 
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