vin H specs

[87305vinH]

87 monte carlo with the 305 vin H motor still trying to find out what exactly the differance between the vin G and vin H were. If anyone knows the true HP and torque for this motor and the G motor let me know. I also found that the H motor is OHV. Which i can imagine only stands for over head valve, but i didnt think OHV was introduced to the v-style motor. Thanks for your help.

 

[85 Cutlass Brougham]

Overhead valve means it is not a flathead. If it were, there would be no need for valve covers and rocker arms. So, valve in head=OHV. Valve in block= flathead.

As for specs, it is an RPO LG4 305. It has about 150hp stock vs 180-190hp for a G code L69 305 HO. The L69 had bigger valves, higher compression, and a 350 cam in it to make the extra power. The L69 also had the larger oval inlet cat and free-er flowing exhaust. In addition, L69 cars came with 3.73 or 3.54 gears as compared with a 2.41 which is common on LG4 cars. The L69 had 9.5:1 compression, and I think the LG4 has 8.5:1.

 

[87305vinH]

Thanks brougham

Thank you for finally giving me some answers. I don't know why i didn't think of OHV that way, i guess i was jus thinking of them damn j* engines. I'm gonna have the heads redone, port polish and i would like to go with bigger valves, got any idea what route i should go there or should i ask the machine shop? I have everything else except for ignition, got any recommendations for that? Much appreciated.

 

[85 Cutlass Brougham]

Well, before you spend any real money on a 305....don't. Get a 302 (Chevy-not Ford), 327, 350, or 400 small block instead. The 305 can make power, but by the time you do it will cost too much and still be less powerful than if you had put the same money in a 350 instead. The bore is too small which limits valve sizes, a crucial problem with only 2 valves per cylinder. To put it in perspective, my 2.4 liter Nissan DOHC KA24DE 4 banger in my 300k mile Frontier has 143hp, or about the same as your LG4. The 240SX version of the same engine has 155hp, or 5 hp more than your 305. It also has a smaller bore and larger stroke, but the 4 valve head means it still has more overall valve area than the 305. So, flow is not restricted, and it makes the same power with less than half the displacement. Pushrod V8's only make sense with a large bore. This is why most popular performance 2 valve pushrod V8's have at least a 4 inch bore. It allows for enough valve area to have good flow on a small block engine.


BTW, "j*" is considered a racial slur and not advisable on an open internet forum. You do not know the nationality or ethnicity of the people you are trying to get information from. I may not be Japanese, but I do not like using such slang.

 

[87MonteSS]

As for specs, it is an RPO LG4 305. It has about 150hp stock vs 180-190hp for a G code L69 305 HO. The L69 had bigger valves, higher compression, and a 350 cam in it to make the extra power. The L69 also had the larger oval inlet cat and free-er flowing exhaust. In addition, L69 cars came with 3.73 or 3.54 gears as compared with a 2.41 which is common on LG4 cars. The L69 had 9.5:1 compression, and I think the LG4 has 8.5:1.

The L69 also has a factory aluminum intake.

 

[85 Cutlass Brougham]

The LG4 has an aluminum intake too, and it's the same one as the L69.