Thinking about a stroker

[Reliabilityman]

What about the trick flow 240 head and a 440 source stroker kit stroking a 440 to a 512.? Simulated Im getting 525HP @5000 RPM and 645 ft-lbs at 2500?? Real world...yet to be determined but it should move a large heavy C-body rather nicely for the street. Roller cam and all!

 

[weim55]

I’m going to take this a slightly different direction, but stay on topic of your original desire to get that big car moving with plenty of low end torque.

I’ve done my share of engines over the years and I’ve recently come across a repeatable combination that has me pretty smitten. A 65 Chevy C 10 that weighs about the same 4200lbs. as your Chrysler. This is just an old fun truck that I’ve had for 30+ years. I have “robbed” good engines from this truck for other projects and basically haven’t really cared what’s under the hood as long as it gets the job done. After another situation left this truck engine less. I quickly whipped together another 350 to get her back on the road. The idea was to do this on the cheap with his many parts on hand as possible.
It’s a stock bore flat top piston with the original GM flat tappet truck cam.
GM performance, dual plane, 1 1/2” long tube headers. 2000rpm Torque converter (it actually brake stalls AT 2,000rpm exactly) compression ratio comes in at just under 10to1.
The kicker is the cylinder heads: 96-99 small valve, small chamber, 305 Vortech cylinder heads. Nobody uses these heads because of the small valve and essentially why would you?
But I had a really nice set on the shelf that needed nothing other than lapping so on they went.

The last ingredient is I live and drive at altitudes between six and 7000 feet. This puts me 20% down on horsepower and throttle response here is hideous. A stock engine in razor sharp tune is lucky to get 15/16 inches of idle vacuum.

This 350 is stunning. The off idle response is unbelievable for the combination. From idle to 3500 RPM where truck spends 99% of it driving time I couldn’t ask for better anywhere. Because of the Stock cam. It idles smooth as glass and idle vacuum is excellent for the altitude. The carburetor is just a well tuned comp series AFB that has been on the truck over 30 years and probably 10 different engines easily. Has fuel injection response, better than any other engine it has been on.

Truck is SO much fun to drive now! To call it snappy would be an understatement. Tickle the throttle from any cruise MPH and the truck gets with it NOW. I would not call the engine a powerhouse. It does pull STRONG to 4500rpm+ , It is NOT pulling your head off your shoulders at high RPM.

How does this have anything to do with the original question? Well, oh how I wish the 383 in my Chrysler 300 ran like this 350! I don’t wanna have to admit it, but yes, this 350 will run circles around that stock 383 in absolutely every category. I’ve come to the conclusion, I don’t need the cubes, I need the efficiency!

After three decades of putting together various Detroit V8s the one thing I have learned over and over again: power and manners are in cylinder heads! I am very tempted to try a set of TFS240s Or methodically ported 906s on my 383 with good intake and exhaust components To hit the goal of what I’m looking for: a super fun to drive Chrysler 300! I don’t need the car to burn down the dragstrip, I have other vehicles for that. But I do want the old Chrysler to live up to the thunder 300 badge should have.

Sorry for the long, random thoughts, some food for fodder……….

Steve weim55 Colorado

 

[Reliabilityman]

I’m going to take this a slightly different direction, but stay on topic of your original desire to get that big car moving with plenty of low end torque.

I’ve done my share of engines over the years and I’ve recently come across a repeatable combination that has me pretty smitten. A 65 Chevy C 10 that weighs about the same 4200lbs. as your Chrysler. This is just an old fun truck that I’ve had for 30+ years. I have “robbed” good engines from this truck for other projects and basically haven’t really cared what’s under the hood as long as it gets the job done. After another situation left this truck engine less. I quickly whipped together another 350 to get her back on the road. The idea was to do this on the cheap with his many parts on hand as possible.
It’s a stock bore flat top piston with the original GM flat tappet truck cam.
GM performance, dual plane, 1 1/2” long tube headers. 2000rpm Torque converter (it actually brake stalls AT 2,000rpm exactly) compression ratio comes in at just under 10to1.
The kicker is the cylinder heads: 96-99 small valve, small chamber, 305 Vortech cylinder heads. Nobody uses these heads because of the small valve and essentially why would you?
But I had a really nice set on the shelf that needed nothing other than lapping so on they went.

The last ingredient is I live and drive at altitudes between six and 7000 feet. This puts me 20% down on horsepower and throttle response here is hideous. A stock engine in razor sharp tune is lucky to get 15/16 inches of idle vacuum.

This 350 is stunning. The off idle response is unbelievable for the combination. From idle to 3500 RPM where truck spends 99% of it driving time I couldn’t ask for better anywhere. Because of the Stock cam. It idles smooth as glass and idle vacuum is excellent for the altitude. The carburetor is just a well tuned comp series AFB that has been on the truck over 30 years and probably 10 different engines easily. Has fuel injection response, better than any other engine it has been on.

Truck is SO much fun to drive now! To call it snappy would be an understatement. Tickle the throttle from any cruise MPH and the truck gets with it NOW. I would not call the engine a powerhouse. It does pull STRONG to 4500rpm+ , It is NOT pulling your head off your shoulders at high RPM.

How does this have anything to do with the original question? Well, oh how I wish the 383 in my Chrysler 300 ran like this 350! I don’t wanna have to admit it, but yes, this 350 will run circles around that stock 383 in absolutely every category. I’ve come to the conclusion, I don’t need the cubes, I need the efficiency!

After three decades of putting together various Detroit V8s the one thing I have learned over and over again: power and manners are in cylinder heads! I am very tempted to try a set of TFS240s Or methodically ported 906s on my 383 with good intake and exhaust components To hit the goal of what I’m looking for: a super fun to drive Chrysler 300! I don’t need the car to burn down the dragstrip, I have other vehicles for that. But I do want the old Chrysler to live up to the thunder 300 badge should have.

Sorry for the long, random thoughts, some food for fodder……….

Steve weim55 Colorado

So its funny you post this as I have had very similar experiences. Smaller valve engines will be snappier and produce more torque in the low RPM's than larger valve engines. I have built a 401AMC with 304 heads, a 350 with 307 heads and have had the same results you are talking about. Ironically to match your comments even closer, in high school I drove a 71 C10 which had the 350 and 307 heads. It did have a cam and a 600 CFM carb/alum intake and headers, but the rest of the engine was a stock reman 4 star. My friend had a 70 coronet with a 383 and 727. I don't know the gearing in the rear end of the Coronet, but my old rusty truck had a 3:73 axle ratio and a manual 3 speed transmission. The 350 in the old truck beat the Coronet every time from a rolling race (rolling 10MPH up to 60MPH). It was rather funny and we of course gave my friend with the coronet trouble about it then and to this day!! However when you get into the big volume cubic inch engines, I dont think you can beat the torque or HP due to the shear volume the engine is displacing. The only question I wonder is if the larger the rotating mass, the less quick the RPMS ramp up??

 

[NitrousTuner1]

So its funny you post this as I have had very similar experiences. Smaller valve engines will be snappier and produce more torque in the low RPM's than larger valve engines. I have built a 401AMC with 304 heads, a 350 with 307 heads and have had the same results you are talking about. Ironically to match your comments even closer, in high school I drove a 71 C10 which had the 350 and 307 heads. It did have a cam and a 600 CFM carb/alum intake and headers, but the rest of the engine was a stock reman 4 star. My friend had a 70 coronet with a 383 and 727. I don't know the gearing in the rear end of the Coronet, but my old rusty truck had a 3:73 axle ratio and a manual 3 speed transmission. The 350 in the old truck beat the Coronet every time from a rolling race (rolling 10MPH up to 60MPH). It was rather funny and we of course gave my friend with the coronet trouble about it then and to this day!! However when you get into the big volume cubic inch engines, I dont think you can beat the torque or HP due to the shear volume the engine is displacing. The only question I wonder is if the larger the rotating mass, the less quick the RPMS ramp up??

Nope that rotating mass is ineffective (unless we're 7000rpm+). By using the 400 block it has a 4.34" bore size increased over the 383's 4.25"
Large bore with a long rod & shorter stroke = High Rod Ratio which = RPM loving combo.
Camshaft will be most crucial to determine powerband window...
It blows my mind that soooooo Many folks still NEVER spend 15-20 min & CALL THE CAM COMPANY!!
Be honest & explain the build & what you want. Most of the time a custom ground cam will be chosen. The minor increase in price elevates the power on the dyno to pick up the average from idle to max rpm.
YES it might only make 12hp peak More. BUT at 2300rpm it make 35 more hp...
That's a different driving car.