Where to start?
When I bought my car the owner was unsure of the actual HP. He believed it was a 250-hp that had been bored out so thought it to be in the neighborhood of 300. Not sure about that though
I personally am not sure of the differences in the 250 300 motors , but would guess it was compression and maybe cam. As of now the the motor has a oil leak in the valley and am considering doing some upgrades while doing the repair.

Upgrade one is a new manifold, I was thinking a edelbrock performer.

Upgrade two is a new set of aluminum AFR heads, but have two questions regarding this upgrade.
1. could I use the same head when I eventually stroke the motor to a 383?
2. will I be able to fit old school aluminum valve covers on these heads and if so will roller rockers fit under them?
3. what kind of power can I expect from a 327 that has been bored over and is running the previously mentioned mods? I would expect in the neighborhood of 400 if it were a 383, but am not sure what to expect from a 327. Maybe 350?
4. If I still want to keep the torque the motor has can I keep the same came or would a hotter cam be a better choice?

I should also say that I'm trying to keep the motor looking more original than after market looking.


The alternative to this thinking is to say the hell with it and go to a LS 2 which I know has 400-hp and is 100lbs lighter, but I'll ask questions about that option in separate thread.
Toby

 

Toby, if the engine pad is still in tact and you believe the engine is the original, check the pad. A 250hp engine will end in RC and a 300hp engine will end in RD. For example if it said F0222RC, this would be a Flint built engine, built February 22 and have 250hp.

The other numbers on the pad should be a derivative of the VIN number.

If you have the original block, stay with it, the car is worth more!!

Harry

 

Motor is NOM. If I rember right some one said it was a passanger car 327 by the numbers.
Toby

 

Toby, you can get all kinds of power from a 327, just look at the factory HP rating through the years. It just takes the right combination of parts. My engine is a reasonable example. 327, .030 overbore (331ci), fully balanced, forged pistons, 327/350 cam, Edelbrock Performer manifold and 625 carb, matched ports on iron heads, w/roller tip rockers and alum. intake, performance ignition, headers, fresh-air induction (home made). I have run 13.5 at the track, but have a real traction problem, more commonly known as low end torque. I guess 380-400HP and plenty of torque. I don't think you can safely get a 383 out of a 327, correct me if I wrong, but traditionaly a 350 is used with a .030 overbore and a stroker crank. Not sure of the application of the alum. heads, but the roller rockers may interfear with the oldschool valve covers. Others here on the forum will certianly have some observation on this. Dennis

 

I think your choice of a performer intake and those heads will be great. Keep in mind that if you want your engine to spin more than 5200 rpm or so you will want some really good connecting rods in there.

Many 327's were lost to a busted rod.

The best practical rods for a 327 are the Crowers. They are 585 to 600 grams which puts them very close to the originals and won't require major rebalancing. The Scat and Eagle rods are way heavier and I have heard they are made in China.

A good choice for a street motor would be the 327-350 hp (L79) configuration with the hydraulic cam and lifters. It may not rev as high as the solid lifter cams but you'll have that torque peak right where you want it.

(props to Dennis, whose post I failed to read entirely)

 

It's OK Seaside, I'll blame it on your nice weather. Your rod thought is very good. I have been lucky sticking with the original rods with new bolts. Dennis

 

I thought the 340 and 365 had 6500 rpm redlines. Do you know if they ran different internals?

 

I talked to a guy at AFR about this today. He recommended their 180 heads for a 327, but said you could also go with the 195, but would be looking at a higher RPM motor. Which makes me wonder how high I can spin this motor without having to rebuild it to do it. He thought the 195 would work well on the 383, but said you could use either on both applications.
The only way this motor gets rebuilt is with the body coming off because of the 5 speed PITA factor. And in that case It becomes a stroker for sure, but I don't feel like doing that now.

One question I have is does the compression change when the head size changes 180 to 195 say.

They had a test motor they built that was a 350 with a 180 heads a rpm or similar manifold and a holly 650 that put out 420-hp at 6500 with a very mild cam and hydraulic roller lifters if I remember right.
Very encouraging.
Toby

 

theybot,

On your 4 questions,

Can't help you on #1 (didn't stroke mine).

On #2, Yup & Yup (see pics)

On #3, I've never dyno'd my current setup but she's run 13.6's @ 103.6 mph with a lot of tire spin at the track. Think that works out to 282 rr wheel horsepower.

On #4, you definitely need more cam.

Here's 2 choices for you which I've used:

Keeping her hydraulic:

SpeedPro's CS186R (Hydraulic cam [almost mirrors the factory 350 horse): 230/230 Intake/Exhaust w/a lift of 480 both Intake & Exhaust on a 109 LSA.

Going to solids:

SpeedPro's CS1145R (Solid lifter LT1 cam): 242 Intake w/259 Exhaust; Lift is 459 Intake and 485 Exhaust...all this with a 116 LSA

Lift on both cams w/b w/ 1.5 ratio rockers.

Mine started out life as a 327/300 horse. During its 2nd rebuild, I decided to go the solid lifter route and installed the '70-'72 LT1 cam, lifters and LT1 service replacement intake for those years. In addition I replaced the '461 heads with Dart Iron Eagles (180 runners) which were ported/polished. I kept the ramshorn manifolds (2 1/2" in '65), but did go for the Sweet Thunder GNM (Gives No Mercy) side pipes (3" OD, 2 1/2" ID) vs. the factory 1 7/8" ID pipes. The laundry list of changes includes an MSD6AL box, Pertonix ignition and the factory correct Holley 2818-1 List. The Corvette valve covers will fit on the aftermarket heads because of the higher ridge of these heads. They will clear for the install of 1.6 roller rockers.

Here's a few recent pics of her:





I'll dig out a pic or 2 of the 1.6 Crane Gold roller rockers I'm using.

'Course I've since put another variable in the mix adding Classic Auto Air last winter. She still humms.

Good luck with your choices.

Regards,

Jim

 

IMHO; If you are going to spin high, go with the crower rods.
brgds
rene

 

That's true. The solid lifter motors had the pop-up pistons, the Duntov 097 cam or the 30-30 cam and the big-valve heads.

The 250 hp had smaller valves and ports plus the 2" exhausts.

Hydarulic lifters limited revs to about 5400 or so. That's why if you're going to higher rpms you'll need the better rods. Rods are cheap compared to blocks.

Speed-O-Motive has a 383 stroker crank for the small-journal 327 block.

 

theybot,

Like rene-paul and Seaside63 have stated here (as well as others), you do need to upgrade the rods. Crowers are the way to go. Anytime your spinning above 6K, you do need that confidence these rods bring.

Here's that pic of the 1.6 Crane Gold roller rockers under the factory valve covers.





Regards,

Jim

 

But were the rods different in the 340's to the 250 300s, or for that matter between the passenger car 327's.
from what I can tell it seems like the bottom ends of the 327 were basically the same with the exception of maybe pistons.

If I were to swap rods can I do it with the block still in the car. I know it would be a good time to drop a speed o motive crank in, but like I said earlier it would be easier to pull the body to do the motor than to try and get that thing out now that the 5 speed is in there. And that just aint in the picture this year.
Toby

 

Is there a compresion change ffrom a 180 head to a 195? My guess is yeas, but don't really know.
Toby

 

No

The difference is the intake runner size. 180cc vs 195cc.

 

Got it .
Thanks

 

All the 327s in that period used the same connecting rods.

You can do it with the block in the car but you definitely have to pull the heads off since the pistons have to come out.

 

Pull the engine - you have to have it re-balanced anyway when you change the rods.