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two cups of tea
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Ok so I got lucky today when I went to my grandpas friends shop to borrow a compression gauge, to use on an engine I was going to see he told me he will sell me a 350 he has out of a gmc van&long as I buy all of the parts we will put in a cam&new pistons&rings&bearings&timong chain.well he owns his own shop I told him I want to use my 305 heads so I recently found out they were pocket ported&when they were on my 305 my compression was 8.5to1 I'm wondering what all do I need to have done for then to run good on the 350 at high rpms?he told me tell him what I want done to my heads&he will have them done for free.also I'm on a budget so out of my summit or jegs catalog do you guys have any suggestion on a peasonable cam&pistions&rings etc?
 

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Depends on what you consider high RPMs. I described a 350 I built with a similar setup in another one of your threads. I think that screw in stud & guideplates would be a good upgrade if you heads do not already have them.
The drawback here is that you need to use hardened pushrods & they can be pricey.
My engine was a good daily driver & was fun to drive. I would run it up to 6000 rpms with no problems.
My set up was a 350 4 bolt main block with stock deck height.
cast crank
PAW stage II rods
TRW 2256 flat top pistons with the 4 valve reliefs
A Comp Cams 280 magnum hyd cam. I also think that the 286 magnum may be a good cam for this engine if they still make it. It will help bleed off a little compression. I strongly suggest using the valve springs matched to the cam.
A double roller timing chain.
A set of 305 heads that were stock except for the screw in studs & guideplates.
I also ran the Comp Magnum roller tip rockers 1.52 ratio
Performer RPM Intake
Holley 600 Dbl Pumper carb.
I hope this is helpful.
 

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whats the casting nubers i used some 305 heads that were 601s they came off a 305 from a 4wd 83 truck.I worked'em a bit and they were nasty up to 7.000 on my 350 but i used a little speed pro 327 cam ill get the numbers if you want and some speedpro flat tops had the block surfaced i had an old crank i polished up nice and ran hyd/roller lifters molly rods and full roller crowler rockers and a victor JR intake w/demon dominator 650 was sweet set up ran like a raped ape and would turn 7800 scary to do but it would and i only had $1.358.00 in it
 

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o yea motor dynoed at 374hp @6200 and to make things flow right slot the intake holes just a bit left to right and gasket match heats and itake then when it all goes togather like up the intake ports and head ports then crank it down
 

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cutthroatkid said:
Ok so I got lucky today when I went to my grandpas friends shop to borrow a compression gauge, to use on an engine I was going to see he told me he will sell me a 350 he has out of a gmc van&long as I buy all of the parts we will put in a cam&new pistons&rings&bearings&timong chain.well he owns his own shop I told him I want to use my 305 heads so I recently found out they were pocket ported&when they were on my 305 my compression was 8.5to1 I'm wondering what all do I need to have done for then to run good on the 350 at high rpms?he told me tell him what I want done to my heads&he will have them done for free.also I'm on a budget so out of my summit or jegs catalog do you guys have any suggestion on a peasonable cam&pistions&rings etc?
well i t is great to hear from you.. i think you know much... i have a car and it is liberating too much smoke like a **********what can i do to overcome it...
 

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two cups of tea
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Discussion Starter · #10 ·
I'm the wrong person to ask,I'm just a kid&still learning but these guys on here are great...you should ask in hot rodding basicis...but Ill help if I can what type of car&where is the smoke coming from&what color is the smoke?
 

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From your combo outlay and since this is a street car you need not worry about high RPM power. Ask yourself this question, how often are you at wide open throttle on the street? Very very seldom. Cam and valve train dictate RPM`s with a iron fist. Sure, you can stick a big cam in it with the right valve train and it`ll rev up to 7500 RPM, but, not only will this cost $$$ but it will also require a 3500 stall converter, 4.56 rear gears, a single plane intake and a larger 750 carb. The low gears will be needed to compensate for the lack of low end torque caused by the big cam and open plane intake. If it was ran like this on the street you wouldn`t be happy, as it wouldn`t have enough low end torque to burn a tire. you would have to keep the RPM`s up all the time so the engine would be in the upper torque band just to move the vehicle. A cam is not like a switch and there is no cam that does it all. You get a cam for low end, midrange or for high RPM, there is no cam that does it all, 1 of those three things will be the area it`s good in. You learn to read cams by the duration @.050 figure, don`t look at the advertised duration. You also pay close attention to the LSA and ICL of the given cam.
Also for high RPM usage the heads will have to be heads that will flow well at high RPM, in turn, the compression ratio would have to be higher, and forged pistons a must. So you see, you have to stick with what you have and work with it. Don`t be concerned about how much top end power it`s going to have, you don`t need top end power on the street. I`ve said this many times already and I`m not going to repeat it again, focus on the torque of the engine, not horsepower. Torque is what moves the vehicle, not horsepower. Torque is what smokes tires, torque is what win`s races, not horsepower. This is just the start of it all since your learning but remember, when you do a build don`t plan the whole build around 1 part, the whole combo must match to make maximum power. It takes the whole team to win, not that 1 part. To give a better example of what torque can do, send me a PM sometime and ask me about the cutlass versus the 65 chevy truck.
 
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