Will these Heads work???

[diego-ted]

I am trying to follow the 400 hp build on my 318, but am having trouble finding 302 swirl port heads. I was reading in the mopar builders book that the 308 Smog heads would be good to use if I pluged the air pump holes and milled the heads 40k and milled the intake surface around .o38. Is this true? and how would they compare to the 302 heads.
Thanks guys.
diego

[diego-ted]

come on guys what do yo think.

[Kevin Garceau]

I think you will be a 150 hp short of their 400. Unless you have 2500 to spend on porting those 302 heads.

[345Dart]

308s will work just fine in my opinion. The 308s have 1.88/1.625 valves which is what the 302s were changed to in the article (maybe 1.60Ex).
The 308s are open chamber and stock have CC of ±72cc vs the 302s are closed chamber and stock have ±55ccs. This is why you need to take at least .040 - 0.050 off to get the CC down in size. This may lead to custom length pushrods and the need for adjustable rockers.
An option you have is to leave the CC of the 308s at ±70cc and compensate with new pistons to reduce the combustion volume to give you the final compression ratio you are after. (obviously my recommended method to follow)
The 308s are the lastest LA head design for 360s and with a 3-4 angle valve job using the stock size valves and some light cleanup of the bowl and runners will give you as much or more flow and velocity than a totally reworked (read exspensive if not done by yourself) set of 302s. It also allows the use of a 340/360 intake with very little runner port matching required.
I'm sure you will get other comments and versions, but for the dollrs I think this is the better avenue for a 318 and later gives you some good components for a larger 360 build.
M2CsW

[fastmopars .inc]

i have never heard of paying 2500 dollars to get a set of heads ported! i paid 100 bucks for my mechanic to port my heads and the car goes mid 11's on pump gas with stock mopar heads.

i would think you should have no problem with the 308 heads and that kind of power, especially if they are better than the 302 heads like 345 dart says. the 302 heads were designed for the 318, that's why the combustion chamber cc's are so much smaller. you will need to push the compression ratio to the edge of pump gas-ability (probably 10.5) to achieve 400 hp with a 318, and i highly doubt you can do it with a hydraulic cam. but a solid cam with about 234 int and 238 exhaust should do it. post the results when all are said and done, but if you only go low 13's you could have just stole a magnum 318 out of a new truck and be done with it.

[diego-ted]

Originally posted by fastmopars .inc
i have never heard of paying 2500 dollars to get a set of heads ported! i paid 100 bucks for my mechanic to port my heads and the car goes mid 11's on pump gas with stock mopar heads.

Man I could send you heads all day long and we could become rich if you could get a good port job for $100.00 bucks. Send me your address!!!
Ted

[Kevin Garceau]

you never heard of 2500 dollars in porting on heads?

Let me ask you this, you buy a set of heads and want them to flow like Darrell Aldermans? How much in time do you think are in a set of heads like that? As Ted said you could be rich if he did a good job for 100 bucks. But is just as easy to ruin heads as it is to make power. For a hundred bucks I will clean up a set of heads, take some of the flashing out, and polish them a little here and there, but that is not porting.

That 400hp small block build up had TONS of head work. I believe this had been hashed out already in this forum. Its a bogus article. They didnt charge for the headwork is why it stayed so cheap. Dont you think if 400 hp 318s were that easy everyone on this board would have one?

[Mills]

I think I had the same dispute w/ a guy here who wanted (and thought it was possible) to run mid 10's in a 3800 lbs B-body 'Cheaply'. He was having 'some guy' port his heads.

My response was similar to yours ' if it was SO easy, why wouldn't we all have mid 10 cars '

Getting back on topic, I think a 400 HP 318 would be VERY unstreetable....although some people may have a different view of what streetable means. A 300 HP 318 is a potent ride in my mind.

[diego-ted]

I agree, If I can get 300-325 out of this motor I will be very happy, it's going in a 66 Barracuda so this will be a fun car when I'm done. I'm not going to waste time on a dyno to find out what my end result is. I'm just trying to do a quality build on a 318. listed on the link below is more of the results I'm expecting.
Ted

http://www.geocities.com/alwest_83/318

[dwc43]

Originally posted by diego-ted
I am trying to follow the 400 hp build on my 318, but am having trouble finding 302 swirl port heads. I was reading in the mopar builders book that the 308 Smog heads would be good to use if I pluged the air pump holes and milled the heads 40k and milled the intake surface around .o38. Is this true? and how would they compare to the 302 heads.
Thanks guys.
diego

All you need is a set of 2.02 1.60 valved X or J heads. The will out perform the 302 anyday. A little clean up will not hurt either on the exhaust side.Then mill them about .035 to get around 62 cc's. That's all you need.I've been building racers for years and this is the best and only head to use until you go to the aluminum and then to the w-2 race heads. You can get 400 plus from a 360 for much cheaper though and still run pump gas too.
Next step up would be the aluminum edels.

[Mills]

I would do exactly what they are saying. As long as your shortblock is in good shape - i.e. leakdown test - you should get your HP that will make a nice ride.

My only suggestion away from what that article said - get a Hughes or Comp cam. I know there will be some guys that will want a custom ground Racer Brown, but my vote is for the Hughes. I would suggest the HE1423 or HE1923.

[Mills]

I would stay away from the 2.02 intake valves. X heads are great for larger 340 or 360's, but the J heads and 1.88 would be a better choice for your mild 318 for velocity. Also - too much $$ for these

Your current heads, w/ simple prep per the article, will do what you want your engine to do. With the Hughes cam, you will also have more low and mid then the MP cam...right where you want it with an engine like this.

[dwc43]

The J heads are the sam as the X heads and can be had with the 2.02 valve too. And this is what you want. The velocity will be fine on the 318. We've built several for claimer rule tracks using these heads and they are not expensive. I have several sets just lying around waiting for my next project. This is the best heads and valve sizes to use and will get you away with out a hole lot of porting.

[diego-ted]

Thanks to all.