is there any difference between 289 and 302 heads, what would happen if i put 289 heads on my 302. just curious.
they are the same basicly. depending on the year 302, the chamber volume will vary. so 289 heads would raise your compression ratio. also watch what style rockers you need for the head you use. some heads have slots to guide the push rods, some use rockers with rails for alingment, and some use rocker folcrums. i think most 289's had the slots. but with the cost of rebuilding a set of old heads, there are so many better choices out there, performance wise anyway!
The early 289 heads had smaller chambers and smaller valves than some of the 302 heads. That would limit your breathing and increase compression - not a good mix except for economy and low revs.
A lot more options for heads now compared to 20 years ago. I have a set of bare 68 302 4V heads that are pretty much paper weights. Tried to sell them a few times with no luck.
Either people are giving away those old 302 heads for next to nothing or some people think they have a gold mine and want outragious amounts of money for them. I have seen them sell at both ends of the scale but rarely for what they should be worth. lol
I almost threw them in the truck for the dump last weekend. Thought better of it. Last time I did that I threw out a Grabber spoiler.DUH(before ebay era)
I thought those were actually pretty good heads, right? Small-chambered like the 289's but bigger valves?
Thats why I kept them all these years. Small chamber heads. By the time you build and port these things though you may as well buy new heads. They do look cool with the 4V cast into them though.
yeah but not everyone is building for race. For someone like myself thats doing a factory restoration, those heads would mean a factory look but more power. Actually I am some what interested in buying those heads.
same here, my baby will more than likely never see the track anyway, so why put high hp parts in it. that would be defeating the purpose.
then why are you asking to put 289 heads on it? why not just keep the heads you have? you can use whatever you want, whatever floats your boat. so........... your saying when that camaro pulls up next to you at the stop light, you wont be tempted?????
sure i will be tempted but its not worth having my drivers lisence taken from me. concerning the 289 heads i was just being curious as to what would happen if i did put 289 heads on the 302.
289 heads I put a set of 289 heads on the 302 in my girlfriend's maverick.They are 65 289 heads on a .040 302 with a performer intake,comp 268H cam and Holley 650DP.No matter how much timing I back out of it on 93 octane gas the thing detonates so bad it sounds like it's making popcorn.I suppose if the pistons were dished instead of flattops I would be ok but this thing just has too much compression for pump gas.The only reason I put them on was because the stock ones had a bent valve when I bought the car and I built the 289 heads for another project a long time ago and never used them.None of this is really important since the engine uses 2 quarts of oil a week.The engine is coming back out this summer and an all roller 302 out of my Mustang will be going in its place.Hopefully she won't notice the 3.50 gear swap and 2500 converter that is going in at the same time since she never gets on the highway.Now that I have gotten off the subject,If you do use 289 heads make sure the compression isn't so high you can't run it on pump gas.
You don't have too much compression, you've got the wrong cam for the compression ratio. You need a wilder grind that's got more overlap. The 268H was made for 8-9 to 1 compression ratios.
The 68 302 4bbl heads are identical to the 65-66 289 heads. Just a newer casting. Same ports, valves, chambers
