512 stroker

[rocket70]

Hi Chaps,

Interested to hear your thoughts on what type of cam i should go for on a new build that will hopefully be happening over the winter here in the UK.

I want the engine to look stock'ish so here is what i know...

Street car
Car is a 62 Plymouth (approx 3300 lbs)
Pump gas (97/98 ron)
Stealth heads
Performer or Performer rpm manifold
Factory hipo manifolds with 2.5" exhaust
3.23 or 3.55 rear end
converter - currently 2200 from what i have been told from previous owner but happy to replace with something more suitable if required.

Thank you Bryan

 

[BSB67]

Goal?

Budget?

 

[451Mopar]

The Performer RPM is a good intake, but it is tall and hard to fit under many stock hoods.
If hood clearance is an issue, the Holley Street Dominator is a low profile single plane intake often used.
Are you wanting a flat tappet cam or roller cam, Hydraulic or solid?
Usually when someone posts about a stroker, the first thought is the owner is doing the stroker to go racing, and that is not always the case.
List a priority list of what you want from the setup.
You mentioned stock looking and factory manifolds, but what about idle, sound, power, and such.
Is this just for driving or racing?
Just curious, because I started my 505 as being stockish looking, but used a hydraulic roller cam, roller rockers and roller thrust button, and the engine under the hood sounds like a sewing machine with all the rollerized parts. Really the under hood engine sounds is close to my solid roller cammed 500" engine.
I'd like to see what others have done on builds like this, because I have been gathering parts for another 512, but it has the 27cc dished pistons, stealth heads, Holley SD intake, and I might just use a small hydraulic flat tappet cam in it. I know it will kill power, but it's going into a driver, not a race car.
Some might be confused on why build a stroker for a mild engine, and a big part of that is I hot a bare 440 engine block from a friend, with no other parts, so i needed a crank, pistons and all, so stroker crank was really no additional cost when buying new parts.

 

[496 polara]

If you are building for torque you have a good start. I will say any work you do to the heads will be returned an power/torque everywhere. For something with a good idle and plenty of vacuum something like the comp xe274 will have a stock idle,use stock rockers if needed and make torque everywhere.Probably peak HP around 4800 in a 512(just my opinion).Would be great for 3.23 gears. If 3.55 and you want a little more the comp xe 284 will be stronger everywhere and rpm a little more.

The 274 cam would work with the performer intake but both would benefit from an rpm or Holley street dominator. These cams are just a general guideline. Use whatever brand you are happy with. And yes, a hyd roller will cost more and should also make more power and not have the cam lobe issues of today.

 

[BSB67]

List a priority list of what you want from the setup.
You mentioned stock looking and factory manifolds, but what about idle, sound, power, and such.
Is this just for driving or racing?
Just curious, because I started my 505 as being stockish looking, but used a hydraulic roller cam, roller rockers and roller thrust button, and the engine under the hood sounds like a sewing machine with all the rollerized parts. Really the under hood engine sounds is close to my solid roller cammed 500" engine.

Well said.

I'd like to see what others have done on builds like this, because I have been gathering parts for another 512, but it has the 27cc dished pistons, stealth heads, Holley SD intake, and I might just use a small hydraulic flat tappet cam in it. I know it will kill power, but it's going into a driver, not a race car.

You’ve probably seen this before but here it is again:
This motor:

In this car:

At 4150lbs, 3.23 gear, 1700 rpm converter runs 11.70s at 120+mph. Idles with 15” hg, and drives through the neighborhood in 3rd gear at 1100-1200 rpm.

Obviously nothing is stock. Indy dual plane intake and a “950” Holley.

My motor in the OPs car would probably run 11.20 @ 125 mph

Some might be confused on why build a stroker for a mild engine, and a big part of that is I hot a bare 440 engine block from a friend, with no other parts, so i needed a crank, pistons and all, so stroker crank was really no additional cost when buying new parts.

Exactly.

 

[rocket70]

Thank you guys.
Budget will be around £10k ($13k). It will be purely hot street.

Car also has manual brakes.

I've been reading all the stories about the lifters and thought a roller would be the better choice.

 

[451Mopar]

The 10.3:1 compression 505 stealth headed 440 in the Comp hydraulic roller 236/242 cam and it seems pretty tame in the engine.
I posted an old video here:

This is under the hood with the XT EFI. Like I said, sounds like a sewing machine:

 

[BSB67]

The 10.3:1 compression 505 stealth headed 440 in the Comp hydraulic roller 236/242 cam and it seems pretty tame in the engine.
I posted an old video here:

This is under the hood with the XT EFI. Like I said, sounds like a sewing machine:

Sounds nice.

What is the seat timing and LSA on that cam? 286/292 on a 110?

Seat timing and overlap play a big role in idle quality, if that is important to the OP.

 

[451Mopar]

Sounds nice.

What is the seat timing and LSA on that cam? 286/292 on a 110?

Seat timing and overlap play a big role in idle quality, if that is important to the OP.

Comp shows 286/294 110 LSA, 106 intake centerline, 0.544"/0.541" lift @ 1.5:1 ratio.
I originally tried running the stainless CAT 1.7:1 rockers (0.617"/0.614" lift) and I used just slightly stiffer ISKY 8005A valve springs than the recommended comp 925.
The roller tips on the cheap rockers did not seem to be hardened and were wearing, so they were replaced with 1.6:1 ratio Harlan Sharpe rocker arms, so only 0.581"/0.578" lift.

 

[BSB67]

Thanks.

Your cam has 78 degrees overlap and a bunch more seat timing than mine. Mine had 48 degrees overlap and presents milder than yours at an idle. Said differently, our “street” cam choices are pretty different, but meet our needs

My point is this to the OP: there are a lot of ways to an end point, the details of your goals will help guide your path in cam selection.

Thanks again 451 - Car sounds awesome!!

 

[451Mopar]

In the 505" stroker for the convertible the cam seems pretty tame when driving. I don't have a video/sound clip of it with the larger case walker quiet Flow mufflers. In the video it had the super turbos that came with the TTI exhaust system.
The 505 with 10.3:1 compression, I think the next size up cam would also be a nice combo if looking for something that is not, too roudy on the street, but more than the current setup, but the car is also a manual trans, so don't have to worry about converter stall speed. The current setup runs fine at 1,500 RPM in 5th @ 50 MHP.

The new 512 stroker will likely have an even smaller cam.

 

[Curiousyellow71]

The first 512 we built was around 1994.
We ran a mopar performance 284/.484 cam on 108. We had 1 3/4 headers, 452 heads with bowl porting and 2.08/1.74 valves. 1975 vintage iron intake. It liked shifting at 5500. It was very fuel efficient and loped lightly. With 3.23 we recorded a best of 23 mpg. The cam and heads were swapped off a 440..the 512 did all things better.

In two of our current street cars we are running hydraulic roller grinds running solid roller lifters. (Both cars have headers) pump gas motors and are past 11:1.

Bullet cams 248/253 @.050 .635/.640
lsa 114
Trick flow 243/[email protected] .640/.640(1.6)
Lsa 108

The bullet cam is really quiet. The Trick flow has more valvetrain noise.

 

[70ChargerRT]

In the 505" stroker for the convertible the cam seems pretty tame when driving. I don't have a video/sound clip of it with the larger case walker quiet Flow mufflers. In the video it had the super turbos that came with the TTI exhaust system.
The 505 with 10.3:1 compression, I think the next size up cam would also be a nice combo if looking for something that is not, too roudy on the street, but more than the current setup, but the car is also a manual trans, so don't have to worry about converter stall speed. The current setup runs fine at 1,500 RPM in 5th @ 50 MHP.

The new 512 stroker will likely have an even smaller cam.

Wonder why you got that typewriter sound? I’m running the same cam, 1.6 Harland Sharps, smith pushrods, SD intake, 1,000 cfm x-Flo sniper efi. Trick Flo heads with the stiffer springs, Morel Hydraulic roller lifters and 10.7:1 and I have almost zero noise in the valve train. I’ll try and take a video tomorrow in the engine compartment. I’d like to hear yours run with those quiet flow mufflers.

 

[451Mopar]

Wonder why you got that typewriter sound? I’m running the same cam, 1.6 Harland Sharps, smith pushrods, SD intake, 1,000 cfm x-Flo sniper efi. Trick Flo heads with the stiffer springs, Morel Hydraulic roller lifters and 10.7:1 and I have almost zero noise in the valve train. I’ll try and take a video tomorrow in the engine compartment. I’d like to hear yours run with those quiet flow mufflers.

I think part of the noise is the roller thrust button with the steel timing chain cover, and I noticed the ticking is a louder with the EFI injectors than with the carb setup.
The lifters, not sure of brand, got from Hughes Engines, have about 0.040" pre-load.
My old 451 stroker ran a Bullet street solid roller that was pretty quiet too, 251/251 @ 0.050 duration, 0.621" lift with 1.6:1 rocker arms. I think it was 110 or 108 LSA.

 

[70ChargerRT]

I think part of the noise is the roller thrust button with the steel timing chain cover, and I noticed the ticking is a louder with the EFI injectors than with the carb setup.
The lifters, not sure of brand, got from Hughes Engines, have about 0.040" pre-load.
My old 451 stroker ran a Bullet street solid roller that was pretty quiet too, 251/251 @ 0.050 duration, 0.621" lift with 1.6:1 rocker arms. I think it was 110 or 108 LSA.

That’s strange. Mine didn’t make a difference in noise when I switched to EFi. Mine actually picked up 4 more inches of vacuum, now 12 when I switched to Efi but I still run one of those quiet rotary vacuum pumps.

 

[451Mopar]

Since some of these lifters are designed for thinner oil, maybe I'll try 10w-30 and see if it helps? The clip was with a cold engine.
Lets see the vacuum pump setup! Sounds like a good idea

 

[70ChargerRT]

Since some of these lifters are designed for thinner oil, maybe I'll try 10w-30 and see if it helps? The clip was with a cold engine.
Lets see the vacuum pump setup! Sounds like a good idea

I’m running 10w-40 conventional Driven in mine. I mounted my vacuum pump under the battery tray closer to rad support and ran the line with the Borgeson steering pump hose and then up with the brake lines up to the booster. This is the one I used.
Rotary Vacuum pump 12 V - Brake Booster Vacuum Pump UP28- "Plug and Play" | eBay

 

[John Love]

Sounds nice.

What is the seat timing and LSA on that cam? 286/292 on a 110?

Seat timing and overlap play a big role in idle quality, if that is important to the OP.

The first 512 we built was around 1994.
We ran a mopar performance 284/.484 cam on 108. We had 1 3/4 headers, 452 heads with bowl porting and 2.08/1.74 valves. 1975 vintage iron intake. It liked shifting at 5500. It was very fuel efficient and loped lightly. With 3.23 we recorded a best of 23 mpg. The cam and heads were swapped off a 440..the 512 did all things better.

In two of our current street cars we are running hydraulic roller grinds running solid roller lifters. (Both cars have headers) pump gas motors and are past 11:1.

Bullet cams 248/253 @.050 .635/.640
lsa 114
Trick flow 243/[email protected] .640/.640(1.6)
Lsa 108

The bullet cam is really quiet. The Trick flow has more valvetrain noise.

I just built a 512 stroker with 6 pack, I went with Huges racing steamroller hydraulic cam 242 246 at .50 stealth cnc heads dynoed at 662 ft lbs torque and 603 hp goes like he'll power band starts at 2500 rpm at 430 lbs torque

 

[polyjohn]

hello Bryan,

Got to just love a 512ci engine its a perfect street/stripper!

We have one in a 66 Polara at the moment down in London Town UK.
Edelbrock heads and a Crower street roller 0.550 camshaft.

My mate in Sutton has just had his identical 512 built too.
Thats in a street/strip barracuda so an easy ten second car I bet?

This 512 ran 13.20 in drive at shakey the last meet ever, so sad...