318 Cam

[Jerry Ikemire]

Original post was about putting a 383 in my '73 Challenger...about 2 1/2 years ago. My engine builder, renowned race engine builder in my area throat punched me! We wanted anywhere from 400-425 hp. I picked it up and he charged me twice what we originally discussed and BEST dyno pull was only 352 hp and 408 torque. His excuse..."we were never gonna get those numbers from a 383". Then why didn't he say that the day I dropped it off??? This is a shop that builds 1000+ hp engines for a living!!! And I'm learning I really don't have any civil recourse about the matter so I have to eat it! I will keep the 383 for now...use it in a different build that I hope to recover a little more money on than in the Challenger. That being said I have really lost my enthusiasm with the whole build. I've decided to just put the 318 back in it. I know a lot of car buyers love the "matching numbers" cars...I'm indifferent. But what I want to do is put a slightly larger than stock cam in it. The odometer in the car shows 86,xxx. The engine doesn't show any hard wear on it. But just want to move it down the road as cheap as possible. The only things I really want to do to help performance is a cam, larger CFM 2 barrel and headers (I've already put 3:55 posi in the rear). The vehicle restoration will continue as planned. But I feel "cam stupid" right now and am asking for gurus help in the selection. I think I have read too many articles, threads, specs to be super confused!! Can you help bail me out here? And thank you guys!

 

[Xcudame]

Simple, just put a stock 340 (360hp) cam and valve springs in your 318 and use a 383-2bbl carb! You'll be set! If you don't want to change valve springs run a 360 2-bbl cam. Years ago my dad had a 73 satellite with nothing more than a 328 with a stock 340 cam and 2.45 gears. That thing would scream on the highway until I kissed the top of number 4 piston with an exhaust valve! Still ran, just chipped off a piece of the valve and made a "popping" noise for about six months until we finally tore it down! That's why you need the 340 valve springs!

That's crazy on your 383! The 335hp road runner 383 made an honest 335hp from the factory. With long tube headers, a stock 383 would easily make 352hp!! See article link below.

https://www.google.com/url?sa=t&sou...8QFnoECA4QBQ&usg=AOvVaw2KHNZMd7vGLfQN05XzQY0P

 

[mrmopar340]

Guy had no idea of what he was doing. You can stroke a 318 and make almost 400 from that. A 383 to a 505 is a torque monster hoss. Course a 340 done right with good crank, heads, cam and proper induction can put you a almost 500 from that combo. I sneak up on a lot of people this way. My brother has bought 4 different mustangs trying to outrun me. I just laugh and tell him a 340 with a six pack is only 290 hp on the crank from the factory.... I know, I'm a devil...

 

[Chryco Psycho]

Lunati VooDoo cams are awesome some of the smaller grinds will work in a 318

 

[mrmopar340]

Yeah, agreed. Hughes makes some good stuff too.

 

[Chryco Psycho]

Lunati VooDoo is The grinds created by Harold at Ultradyne , Engle is good also , Hughes can be difficult to deal with .

 

[Ricks72Chlgr440]

Original post was about putting a 383 in my '73 Challenger...about 2 1/2 years ago. My engine builder, renowned race engine builder in my area throat punched me! We wanted anywhere from 400-425 hp. I picked it up and he charged me twice what we originally discussed and BEST dyno pull was only 352 hp and 408 torque. His excuse..."we were never gonna get those numbers from a 383". Then why didn't he say that the day I dropped it off??? This is a shop that builds 1000+ hp engines for a living!!! And I'm learning I really don't have any civil recourse about the matter so I have to eat it! I will keep the 383 for now...use it in a different build that I hope to recover a little more money on than in the Challenger. That being said I have really lost my enthusiasm with the whole build. I've decided to just put the 318 back in it. I know a lot of car buyers love the "matching numbers" cars...I'm indifferent. But what I want to do is put a slightly larger than stock cam in it. The odometer in the car shows 86,xxx. The engine doesn't show any hard wear on it. But just want to move it down the road as cheap as possible. The only things I really want to do to help performance is a cam, larger CFM 2 barrel and headers (I've already put 3:55 posi in the rear). The vehicle restoration will continue as planned. But I feel "cam stupid" right now and am asking for gurus help in the selection. I think I have read too many articles, threads, specs to be super confused!! Can you help bail me out here? And thank you guys!

Race engine builders are often confident in the engines they build but have trouble building others. That is why it is important to find a shop that has real experience with Mopar. Matching components on your build to get what the goal is means everything... and it's not just machining! The guys here have "done it" the way you want things done, so their counsel is golden. The good news is you can do the upgrades they recommend yourself & save a ton of money. Besides that, you'll get the experience & satisfaction of doing it. No question is dumb, so ask away and we'll help!

 

[Chryco Psycho]

I completely agree for example I had 2 customers who were competing with each other both did 71 Challenger 440+6 builds , I ported the heads & did the tuning on the Purple cars 440 , while I did the whole build & tuning on the Orange chall , .
We took both cars to the same dyno & the engine I built had 50% more power than the Purple Chall , the person who owned the Purple Chall took the car home & I never saw him drive the car again .
If the machine work is done properly the engine can be built right now .

 

[Xcudame]

Even though it's old, the Mopar Engines book has a great list of parts for different ETs for each Mopar engine and car body. A quick glance shows as the ETs get lower, the cam gets a little bigger, compression ratio goes up, cylinder heads get more work, rear gear ratios go up and the car gets lighter. An engine is a complete package that needs to be planned. As Chryco Psycho has stated above, one or two components wrong and the engine fails to meet the desired outcome.

 

[mrmopar340]

Lunati VooDoo is The grinds created by Harold at Ultradyne , Engle is good also , Hughes can be difficult to deal with .

Yeah had to get the Hughes dialed in. Took a bit but it has a nice hp and tq to it. I really built too much motor. I think we have all been down that road. It is fun though.

 

[Jerry Ikemire]

Guys I can't thank you enough for your help. It really helped clear up the confusion. In fact, I'm picking up a used 340 4barrel intake for $150 tomorrow. Going stock 340 cam after that and calling it a day!

 

[Xcudame]

A nice 600 cfm AVS carb will work great! Don't forget valve springs!

 

[volunteer]

Simple, just put a stock 340 (360hp) cam and valve springs in your 318 and use a 383-2bbl carb! You'll be set! If you don't want to change valve springs run a 360 2-bbl cam. Years ago my dad had a 73 satellite with nothing more than a 328 with a stock 340 cam and 2.45 gears. That thing would scream on the highway until I kissed the top of number 4 piston with an exhaust valve! Still ran, just chipped off a piece of the valve and made a "popping" noise for about six months until we finally tore it down! That's why you need the 340 valve springs!

That's crazy on your 383! The 335hp road runner 383 made an honest 335hp from the factory. With long tube headers, a stock 383 would easily make 352hp!! See article link below.

https://www.google.com/url?sa=t&sou...8QFnoECA4QBQ&usg=AOvVaw2KHNZMd7vGLfQN05XzQY0P

I agree totally with the cam choice. Been there and done that. Anything larger will not perform with stock heads. More economical choice would be the Summit version with .441 valve lift and 46? degrees overlap. My daughter's (340) Challenger has one and it performs equal to stock - and good mpg. 360/400 versions of 2 bbl. will NOT bolt on to 318 intake. Suggest Performer 360 and small 4 Bbl. - no larger than Holley #1850 (600 vac.) Port size of suggested intake is between stock 318 and stock 360 so some opening up of 318 ports slightly to match will benefit. You will be pleased.

 

[volunteer]

Guys I can't thank you enough for your help. It really helped clear up the confusion. In fact, I'm picking up a used 340 4barrel intake for $150 tomorrow. Going stock 340 cam after that and calling it a day!

Just read this after my other post. Suggest do NOT use 340/360 intake since these ports much larger and very difficult to match - for unobstructed air flow. You can pick up a used Performer or Streetmaster for less than $150. Factory 1968 - 1970 340 intakes are rare and sought after by restorers.

 

[TIMINATOR]

I have a new 340 stock cam. 50 bucks plus shipping. I also have a few alum intakes, single plane(not for your app) and a few dual planes. I'll see what I have applicable for you.
P.S. Making 400 hp in a 383 is as easy as falling off a log!
Shame on that shop!
P.S. streetmasters are gas mileage intakes for looow RPM.
TIMINATOR

 

[Xcudame]

If you already picked up the 340 4bbl intake, it's not completely awful to use it. Two of the sides of the ports will match up pretty well and even with the flow turbulence, it would be better than a 2bbl carb and intake. I say run it so you can enjoy your Challenger.

 

[TIMINATOR]

New 340 Mopar by Elgin cam:
210/220@.050
.429/.444 lift on 112° lobe center
Sorry, spoke too soon on intakes, you really want a performer intake for a lower RPM 318. All I have left from past projects are: performer RPM,
D4B, and Strip Dominator for small blocks. All too big on the ports and too high of an RPM for what you want?

 

[DJCUDA]

Does anyone know where I can get my hands on a Mopar Engines book.

Cheers

 

[TIMINATOR]

I have the Engine book and Chassis book.
TIMINATOR

 

[Chryco Psycho]

Ebay