HP on Mexican 350 4 bolt mains

amp1956

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Just learned of this group, so far great info. I was wondering how to find HP on Mexican 350 4 bolt mains.
 

63Half-ton461

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"how to find HP on Mexican 350 4 bolt mains" Do you mean HP as in horsepower ? yeah so if you're lookin at crate motors and some lower HP replacement engines are made in Mexico , i would say HP rating below 300 hp will NOT have 4 bolt mains, is that what you were asking ?
 

amp1956

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Basically I can't find any information on them as far as horsepower it torn down down now I don't see anything special so i don't have a clue on H.P.
 

63Half-ton461

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Thats ok, What head casting # have ya got ? is it a flat tappet or roller cam ? are the Pistons Flat-tops or dished ? If dished how wide ? Is it a 4 bolt main ? if you can tell cam lift that helps (measure lobe lift with a caliper) tell me that stuff and i can give you a pretty close number on HP ...
 
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amp1956

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Ok heads I will have to look it's definitely 4 bolt main pistons are flat tops and lifters are flat I know it's about an 2000 or I think cam has nothing on it other than a casting number
 

63Half-ton461

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Flat tops are a good sign, as well as 4 bolt , that's higher hp stuff, it will be interesting to see what castings the heads are .... 062 castings , vortec ?
 

amp1956

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I will get that info soon its been raining and they are way back in a truck for storage while block is in machine shop but on another note do you know anything about cams? I was given a comp cam 114122 and it shows 1200 to 4200 power band i was thinking about using it
 

63Half-ton461

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That cam is a step up from stock and will make a noticeable difference, the motor will have a good jump in HP while aiming at making max torque, Carb will be easily tunable as the motor will make solid vacuum, BSFC will be good if not better (because of added torque). Stock valve springs should not be a problem. Good truck, 4x4 cam. Depending on heads, intake, headers and tune, Hp could be 265-290 with a healthy 350-375ish ftlb torque. Stock 350 with a 196 degree cam is making somewhere around 190-240 hp depending on heads and compression.
 

amp1956

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Well now I'm wondering if maybe I should build the 327 with that cam its already a 270 horse or so. stamped numbers on pad are T1005HCH its a 67 or 68 Camaro motor I was told
 

63Half-ton461

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Im still curious what casting # those 350 heads are ?
 

63Half-ton461

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I didn't know there was a 327 in the mix, so you have one of those too, nice .... well if it's a legit camaro motor and it started life as a 4 bbl set up and it has double bump heads it could be a 270 horse motor.

If it has the power pack heads (triangle on top of a rectangle) that's another storey.

So your thinking this motor for a truck ? i think a 327 would be a good motor in a 1/2 ton 2-WD with a 700R4 , or any year of S10/15.

What heads are on it and what chassis have you got to drop it into ?
 

amp1956

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no I actually want to put a very reliable small block into a 55 Chevy 4 door as a cruiser I have a
Fitech 30005 Easy Street 600 HP EFI Fuel Injection and choice of manifolds to use not building a race car just a cruiser with a/c . I go on cruising the coast in Mississippi in October and a few other shows so I want to be comfortable ps I will get head info tomorrow I hope been busy as a kitty in a litter box
 

63Half-ton461

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I ran double bumps (1.94"s) on a short track 372 (destroked 400) ay one time. still a great head on any small block, i didnt put hard seats in em just stainless steel valves.
 

63Half-ton461

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So ya, with those heads that motor could be a 270 horse , cam back in the day to make .82 hp per cubic would have been around 200 degrees of net duration and about .4 lift

If you go to the Comp cams web site and download their camquest engine modeling program you can find a cam similar to your Crane 114122 grind and see that it produces a little over 300 hp in a 327 with 1.94 heads, headers and a dual plane, that cam should work well for your intended purpose.
 
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63Half-ton461

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The 55 has been one of my favorite cars since i was a kid, my other being the 66 chevelle. That 55 with a big drop on it and just a bit of a forward rake with 17" rallys would be one cool sedan !
 
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amp1956

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well I still need to pull it apart I was told it had a stock rebuild a few years back then not run .the Mexican head are casting 83417369 or 89 I tried to post pick but it will not go through
 

63Half-ton461

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33417369...90-up...350..........Gen.I Goodwrench crate motor,"Hecho en Mexico", 76cc

So open chamber heads, so with FT 4 v/v relief pistons and tin shim head gaskets you might just squeeze 9:1 compression out of it. Big chamber with spark plug location low in the chamber close to the piston = an inefficient smog head at best, the only saving grace these heads had is that their NOX emissions were lower. any motor these heads are on will be a gas hog. The best Mpg i ever got from my striped down 78 Blazer runnin a 350 with 882 castings (same head) after RV cam, headers, leaned out Q-jet, head work, ignition, super tune was 13 mpg ! Whatever your plans for that 350 are, better heads are gonna need to be part of the equation ....
 

amp1956

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well I still need to pull it apart I was told it had a stock rebuild a few years back then not run .the Mexican head are casting 83417369 or 89 I tried to post pick but it will not go through
 

amp1956

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I'm glad I asked then I will save the short block and get rid of the heads I still have a few more I need to check out I have a late model 5.7 and another Camaro motor I think it's a 79 z28
 
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