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Hi guys!!! I have a 289 in my Coupe. The guy i bought it from says its a 289 bored out to a 302. I dont know if thats possible or not i'm not an engine buff by any means. I did find out it has 351 heads (D0OE). They put an Edelbrock 2212 Performer Plus cam kit, Performer 289 intake and a Carter 650cfm Carb on it also. I need to know what kinda compression i have. I called Comp Cams yesterday and the guy was askin me this and i was at a loss for words. I want to put a new cam, Performer RPM intake and Holley 650carb, and port-polished the heads. Anyone recommend a street/strip cam. Any replies will be greatly appreciated. HAPPY 4TH of JULY!!!!!!!!Osama's favorite resturant-Thank Allah Its Friday.Thanks agian guys. Any other recommendations will be appreciated also.
Heath
 

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Couldn't tell you the compression ratio

After all I've read, I would NEVER polish the intake ports of a street motor; the rough cast surfaces apparently do much to prevent accumulation of fuel in spots.

I'm choosing a crane powermax dual pattern hydraulic cam....for smaller motors either the 260/276 or the 272/284......I've never been impressed with the performer cam specs
 

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You need to determine which pistons you have to make a prediction on the compression ratio.

As for a 289 to a 302, it's possible. But it takes more that just boring the cylinders.
 

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The guy i bought it from says its a 289 bored out to a 302.

IIRC, the bore would have to be .100" out to get close to 302 CI without putting a 302 crank in there. Likely he just stuck a 302 crank and rods in there (with 289 pistons...the same)...that's OK

Knowing the stroke and piston top configuration is necessary to compute CR. My instinct is, as a 302 with early W heads, the CR will be in the low-mid 9's. The chambers on the W heads are a good 5 cc's larger on average. IIRC, I had to shave the iron heads about .030" and run .300" domes to get 12.97:1 CR on some of the early 302 efforts in the race car with that particular combo.

If you plan on changing cams, to render a valid opinion, I'd need to know the rest of the engine/drivetrain combo and the vehicle's use. Take a look at this page for a comprehensive list. I tend to be conservative so you tell me what you like and I'll tell you what I like...*G*

If you go larger on the camshaft, you'll have to re-check valve-piston clearance and check for coil bind and correct rocker geometry (better safe than sorry)...

Not knowing anything else, I'd go with a cam with around .500 lift, dual pattern, lobe center 112-116, with no more than 220 IN and 230 EX @ .050" lifter rise.

Lastly, and this comes from 100's of hours of experience (I'm not proud of being covered with cast iron dust, trust me), spend most of your porting time on the exhaust ports and valve bowls and transition radiuses. I never touched the intake ports on the W heads on my racing engines other than to port match to the manifold and do the bowl and short side radius work. The particular example I spoke of above (in the CR comments), with a Holman/Moody cam of similar specs to what I recommended, W heads, Edelbrock Torker, 3310-1 Holley and an 8" converter/5.14 gears ran in the 11.20's @ 119 mph in the race car. What made it work was a mild camshaft and high compression...getting the car to leave hard is what gets it down the track fast..

Have fun!
 

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Doubt that the engine was bored to 302. It is possible, but doubtful. IIRC, boring a 289 .040 yields something like an additional 3 or 4 cubic inches.

If the engine has the standard dish-top pistons, the compression is probably somewher between 8 and 8.5 to 1.
 
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Discussion Starter #6
Thanks everyone for your posts. I did find info on the Performer camshaft In 204 Ex 214 Duration @ 0.050. I've got the motor tore down to the block now. Am i gonna have to take it to a shop and have it completely tore down to find out what the motor realy has done to it??? Found the VFM lingo page. I feel like i got Hooked on Phonics. No more racking my brain!!!!!!!!!
 

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Dang, I was looking forward to seeing some info on this thread. Especially since I have the casting 351 heads on a 302. With the addition of pop up pistons, I'm wondering what my compression might be?
IMG_20201002_221633080.jpg
 

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Dang, I was looking forward to seeing some info on this thread. Especially since I have the casting 351 heads on a 302. With the addition of pop up pistons, I'm wondering what my compression might be?
View attachment 771124

The big problem with a 289 is the large bore short stroke. It means the heads by nature of the big bore are going to be on the large size in cc. Roughly every 10cc equals a full point of compression. Ford advertised the A code as having 10:1 which is true only if you go by swept volume and head volume. However once you start adding up how much volume the head gasket, valve relief and dish in piston along with how far down the cylinder the piston is in relation to the deck, well it all adds up quickly and a lot more then you think! What you end up is a A code maybe in low 9's and a C code in low 8's.

The other problem is sbf heads don't breath well on the exhaust. It's a restriction on a 289. The 351W heads have a larger intake port and valve and will flow better. On the bad side they have a larger combustion chamber, you'll loose about a half point. Ah, the exhaust. While the 351W has a larger exhaust valve, the port is that of a 289. Despite having a bigger exhaust valve it doi flow any better. You have a 50 YO set of worn out casting that need to be checked for cracks, cleaned, machined and new parts let alone any port clean up. You're going to have a good chunk of change invested vs aftermarket aluminum heads which typically have are designed for around 9:1 on a larger 302. Another thing to think about is the intake manifold. A 289 intake manifold is usually going to have smaller runners to match the 289 heads and not the 351W heads.

You're better off putting a little time and money into a set of 289 heads. A little port work along with smaller chambers is a better set up. One of my favorite factory heads for a Windsor are the GT40P. They have a 60cc head about the same as a 351W head but they have modern, efficient combustion chamber and flow a whole lot better then the old 351W heads. But again they're factory castings that if need rebuilding, you're better off going aluminum. The P head is a great low buck swap if you have a set outside of a spring change you can just throw out khtsi of taking a can of brake cleaner to them. I wouldn't invest any more then maybe a valve job and possibly cutting them down to bring them to 55cc. I can say though, they do work very well for a cheap upgrade. I'd say about 30 hp.

Getting off topic this is why I just bought a whole GT40P out of a wreck. It worked out so much cheaper. Sold a set of GT40P heads I was going to use on a 302 for what I paid $525. Then bought the motor for $450 and sold off what I didn't want for &175. Bought a used Mustang 5.0 cam for $60. Try doing a flat tappet cam swap for that! Used Stealth intake $80. I did buy a valve spring kit from Alex's Parts. I honestly don't remember how much. Anyway I ended up with a very cheap great running motor.
 

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74, Husk, about the whole 351W heads on a 289 thing,.....yeah, there were popups available just for that,..... had a set at one time. Don't remember the final numbers, but its a streetable deal. And no, the GT40P isn't a HUGE imporvement over the early 351W. Matter of fact, the intake ports and valves in the GT40P are EXACTLY the same as the early 351W. EXACTLY. yeah, the chamber is tweaked a little, and plugs angled differently, that was done for emissions management. The exhaust in the P head IS a little better, but you can do just as well and even better if you spend a couple hours porting the exhausts. LSG
 

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I tried to do the GT40P route and couldn't find an engine with less than 225K miles for under $750 in my area. More than once I was told to come and get it and I'd go and they didn't have it. They are hard to find.
My 302 has DOO8 heads because that's what was on it when I bought it. Also, I've haven't ran the engine yet. It also has the pop up pistons, Harland Sharp 1.7 to 1 roller rockers and a Ultradyne P-9 cam. It's stamped with P-10 but the guy at Bullit cams said P-10 means something else, so who knows!
Anyway, it's got lots of good stuff in it and I don't know how it's going to behave compression wise.
 

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I don’t know compression ratio but i can say it worked for me.

Over 25 years ago, didn’t get all information for future reference.

289 .030 over
Flat top piston 4 reliefs
69 351w heads stock size valves
(Screw in studs and guide plates)
Erson 1.6 roller rockers
Edelbrock performer intake, cam, and 1406 carb
Cheap tri-y headers
Dual 2” full exhaust...thanks CHP...long story
C4
2.80 open 8”...3.25 Currie LSD

No track, no dyno, just fun.
Still learning.
 

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74, Husk, about the whole 351W heads on a 289 thing,.....yeah, there were popups available just for that,..... had a set at one time. Don't remember the final numbers, but its a streetable deal. And no, the GT40P isn't a HUGE imporvement over the early 351W. Matter of fact, the intake ports and valves in the GT40P are EXACTLY the same as the early 351W. EXACTLY. yeah, the chamber is tweaked a little, and plugs angled differently, that was done for emissions management. The exhaust in the P head IS a little better, but you can do just as well and even better if you spend a couple hours porting the exhausts. LSG
My point is if you're looking to do a low buck swap basically just taking a set of heads off a GT40P and putting them on a 289 other then a spring kit and a can of brake cleaner. Compared to a 50 year old set of 351W heads that most likely will need a full rebuild before use. In stock form the exhaust port on the 351W is a lot smaller and doesn't flow as well. Plus the GT40P is pretty much what you're going to find in the junkyards these days. They just make a cheap low budget upgrade.

Yeah I know about the intake ports. I used 351W intake gaskets and they were barely large enough. The P head is very detonation resistant. The Explorer GT40P made I believe off the top of my head 15 hp more then the Explorer GT40, ran cleaner and didn't have a smog pump.

It would be interesting to see a comparison of ported GT40P against ported 351W heads
 

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I agree that the GT40P engine would be the smart choice, especially with it's roller cam and low tension ring package if you can find one. I still hope to find one for my next project, a 66 coupe, but that project is at least a year away.
 

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I know this is a zombie but I was thinking, could you remove the rockers on cylinder e.g. both valves closed - weld/solder/jbweld a small tube to a sparkplug with the ceramic removed and Fill the cylinder at BDC with oil - measure how much it takes, then go to TDC and measure how much oil comes out of the tube - do the math...
 

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But it's a good zombie! Don't fear the zombies!
I think you would need to try the oil method on known quantity to verify the process.
 

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How many threads die with the last words being "Ive got the engine torn down" or "I removed all the interior":sick:
 
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