What all is needed to put performer r.p.m. heads on a 289

[jb1dsl]

they have 190 valves in them.

 

[Max Power]

That's a lot of work for a half point compression.

BTW, you need to get hardened pushrods.

 

[Boo Boo Foo]

if your 289 had the stock heads on it....they had 54 cc chambers....and the edelbrock heads have 64cc chambers I believe..stock compression on the 289 was, what, 9.3:1. As a rule, 10cc of chamber is worth approx a full point of compression, so I would say that your compression with the edelbrock heads will be around 8.3:1 or so. It can/will vary a little, but you can safely assume that your compression will be in the low 8 range.

I need to do some research on this post. For some funny reason, I recall reading once that the 289 had a compression ratio into the 10:1 area. Perhaps that was the K-Code motor? My particular 289 is an A-code block, but it was rebuilt by a previous owner at some point before I imported it down here to Australia. It has the "Cleveland Foundry" Hi-Po heads in it with screw in rocker-studs etc. Certainly, it pings very easily unless I run it on VERY high octane fuel.

I wonder, is there an "easy" way to determine compression ratio on an engine without pulling the heads off?

 

[10secgoal]

I did deck mine .035 with no alignment issues. (RPM 2.02)

 

[jb1dsl]

10 secgoal,
what did it cost to shave them .035

 

[jb1dsl]

I believe I still would be better in the long run to get the rpm's even if I lose a little compression, performance wise.

 

[Boo Boo Foo]

if your 289 had the stock heads on it....they had 54 cc chambers....and the edelbrock heads have 64cc chambers I believe..stock compression on the 289 was, what, 9.3:1. As a rule, 10cc of chamber is worth approx a full point of compression, so I would say that your compression with the edelbrock heads will be around 8.3:1 or so. It can/will vary a little, but you can safely assume that your compression will be in the low 8 range.

According to this "Car Source" engine specs website, the C code 289 was 9.81:1 thru 1965-67 and the A code 289 was 10.01:1 in 1965 and was also 9.81:1 thru 1966-67 lilke the C code.

The K code 289 was 11.6:1 pre April 1964, was 10.5:1 in 1965 and dropped to 10.0:1 1966-67

I'm very interested to know what the ingredients were which made the pre 1965 K code engine's compression ratio so high. Was it con rod length? Taller piston height? Lower deck height in relation to the crankshaft centreline? Milled heads? Surely the data must be somewhere on that....

 

[jb1dsl]

well I got them. I went ahead and milled them .020 and took out the loc-wire o ring off. The head gaskets for loc-wires are double what regular head gaskets cost. They ended up being 2.02 valves. ill post some pics of the new setup and nicely painted engine bay in about a week.

thanks guys

 

[302 coupe]

check piston to valve clearance with those big valves, the eyebrows in your pistons are probably cut for smaller valves.


BooBooFoo, I wouldn't put alot of stock in that source, I've known it to be wrong several times before on various stuff, esp older cars. I'm not real sure what the stock compression is on a 289, I never rebuild 'em stock so I don't really care. At any rate, milling the heads will help maintain higher compression than not milling, so all is well.

 

[jb1dsl]

I'm going to start putting the engine back together tomorrow. I will check the clearence. my cam has .448 intake and .472 exhaust lift so it is a mild cam. it is a edelbrock performer plus cam. this cam is very mild so it should be ok, I hope!!

 

[iskwezm]

it is a edelbrock performer plus cam. this cam is very mild so it should be ok, I hope!!

I heard you cant run 2.02's unless the pistons are flycut a good amount.

 

[HistoricMustang]

I have a 289 that I was porting the heads on but they need a total rework and they are not worth it. I have a chance to get soem edelbrock rpm's for a good price and need to know what I need to put them on. The are rpm's with 190's, crane gold 1.6 roller rockers, locwire gaskets, 7000 miles. I know hardened pushrods, what else?

You need to know when the RPM's were made! You may have to drill "steam" holes in the block if it is an early 289.

Been there and done that!

HistoricMustang
www.historicmustang.com

 

[HistoricMustang]

You need to know when the RPM's were made! You may have to drill "steam" holes in the block if it is an early 289.

Been there and done that!

HistoricMustang
www.historicmustang.com

Went ahead and dug out the information.

If you have one of these Edelbrock RPM's and a early model 289 you will need to do the hole thing:

6021,6022,6024,6025,6026,6027,6028,6029,6031,6032,6034,6035,6036,6037,
6038 or 6039

Here are locations for the holes.

HistoricMustang
www.historicmustang.com

 

[jb1dsl]

yep, I put them on today and drilled the steam hole. The heads had the part number 6025 on them but they had 1.90 valves instaed of 2.02, so it goes to show that you should always measure not trust the part number on the part