415HP from 318ci IS POSSABLE!!

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We run 1/8 mile here and I have a 5200 PTC converter and a 5.43 gear with 29.9 X 10.5 tires. The little engine needs all the help that it can get.
 
Sure sounds like fun though! That engine must be moving some serious air to need 84's. That's a credit to the head porter. :)
 
Imagine this with 1.78 intake valves and 1.50 exh. valves. High velocity and a well designed port makes it work very well. With the engine making 501 HP on gas the head flow shows 243.2 cfm's, but the heads actually flow 230 cfm's. On alcohol the HP go's to 535 HP and the head cfm's would be 259.7 so even though the heads really flow 230 the heads or should I say the engine can be tricked to thinking that the heads actually flow 12% better. The lighter the parts and the better the engine is machined the more you can trick the numbers, roller cams have a big influence on this also.

You can trick a engine up to 30% more than the heads actually flow. This is where the science and the art of building engines comes into play. This just happeneds to be something that I really like to do. Along with tuning them to perfection.
 
That makes sense at there is far more area under the curve with a roller cam. I recently read a dyno comparison between two cams with identical specs with one being a being a fast rate hyd flat tappet and the other a roller and the roller cam had significant gains all across the board.

How you get these numbers from such small valve heads is amazing. As you say, velocity is key but how you do it is a mystery to me. Port shape, transition into the valve seat and the shape of the underside of the valve are all I can think of. Do you use a pitot tube when porting?
 
This goes to show you that over valving the small bore 318 can hurt the output on these small displacement engines. A engine is nothing more than a air pump. The more efficient it is the more power it will make. With valve shrouding and low port velocity, this is proof that sometimes, smaller is better.
 
Nope I use a ball point pen. Sounds kind of stupid but I've seen a 15-20 cfm gain by positioning the pen in different parts of the port to show obstructions or deflections, then make the corrections needed. I did this on the 344/349 engine and those heads flow 212 @ .400 lift on the intake and 198 on the exhaust with 1.78 and 1.60 valves. But because of the cam design the engine will think that the heads are flowing near 300 cfm's. These heads flow 190 @ .300 lift on the intake side. The cam is only .473/.492 lift but the duration @ .050 is 274/270 with a 106 CL. The lobe looks almost square like a roller but it's a hyd. cam. The way this cam works is that a few degrees past TDC the valve opens .150 and stays there for about a 1/4 of the duration then it opens to full lift for a short period and then drops back down to .150 then closes and fires. Dang I must have misplaced the specs..
 
SGBARRACUDA said:
This goes to show you that over valving the small bore 318 can hurt the output on these small displacement engines. A engine is nothing more than a air pump. The more efficient it is the more power it will make. With valve shrouding and low port velocity, this is proof that sometimes, smaller is better.
Click to expand...

Yep! No velocity, no advantage from pressure wave tuning. :read2:

BJR Racing said:
Nope I use a ball point pen. Sounds kind of stupid but I've seen a 15-20 cfm gain by positioning the pen in different parts of the port to show obstructions or deflections, then make the corrections needed. I did this on the 344/349 engine and those heads flow 212 @ .400 lift on the intake and 198 on the exhaust with 1.78 and 1.60 valves. But because of the cam design the engine will think that the heads are flowing near 300 cfm's. These heads flow 190 @ .300 lift on the intake side. The cam is only .473/.492 lift but the duration @ .050 is 274/270 with a 106 CL. The lobe looks almost square like a roller but it's a hyd. cam. The way this cam works is that a few degrees past TDC the valve opens .150 and stays there for about a 1/4 of the duration then it opens to full lift for a short period and then drops back down to .150 then closes and fires. Dang I must have misplaced the specs..
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Interesting method! I learn something new every day! Who made the custom cam? Comp?

BJR Racing said:
Sorry, Smooth69Dart I didn't mean to hyjack the thread.
Click to expand...

My fault. :snakeman: I just can't stay away from a good debate. :-D
 
BJR Racing said:
Nope I use a ball point pen. Sounds kind of stupid but I've seen a 15-20 cfm gain by positioning the pen in different parts of the port to show obstructions or deflections, then make the corrections needed. I did this on the 344/349 engine and those heads flow 212 @ .400 lift on the intake and 198 on the exhaust with 1.78 and 1.60 valves. But because of the cam design the engine will think that the heads are flowing near 300 cfm's. These heads flow 190 @ .300 lift on the intake side. The cam is only .473/.492 lift but the duration @ .050 is 274/270 with a 106 CL. The lobe looks almost square like a roller but it's a hyd. cam. The way this cam works is that a few degrees past TDC the valve opens .150 and stays there for about a 1/4 of the duration then it opens to full lift for a short period and then drops back down to .150 then closes and fires. Dang I must have misplaced the specs..
Click to expand...

That does seem like alot of Duration at .050. I always get a kick out of those that want a ton of lift when there heads won't flow at those numbers. I'm sorry for side tracking this thread also.
 
Soo....there is a lot of discussion going on to building a streetable high performance 318...this is great!...I have read all the previous posts and there seems to be a lot of different opinions here on what combo is the best...the other builds in my opinion seems to be a lot more money then my original post from EM...and to take a high performance alcohol burning engine to run on pump gas seems like a backwards approach...I'll explain why, first of all, I believe the cylinder hone, ring gap and higher compression are specific for burning alcohol...am I wrong?

I believe the right combo is one that works for you...maybe you want a lot of lopey idle or just a little shake...the key component to any engine build is the cam and head valve combo...other key factors that play a role is velocity and intake to exhaust ratio which the 2.02x1.60 valve combo seems to work well...if a home builder took his time to cc the intake, exhaust port and chambers...port match the gaskets on both intake and heads and I believe it will make a huge difference on the idle quality and throttle response...basically, if you can build a engine, I feel that you also have the capability to cc the heads as well...if your hesitant to doing it yourself there are books that come with most porting tools kits.

Does anyone have a breakdown on their own build and paid the big bucks to have it dyno'd?...I would like to see what combo's are out their and what kind of power you're making.
 
Smooth,
I hone all my engines the same as it's mainly for ring seal for a given ring, as for ring gap this is in reference to where the ring actually sits on the piston and how close to the top of the piston and what the piston is made of more then how wide it really needs to be. So I guess the distance from the top determins the ring gap. Closer to the top the wider it needs to be, father away the tighter it can be. It's all relitive to how much heat the piston is going to see.

As for compression on alcohol anything over 150 psi will burn alcohol, so you could have a 9:1 engine and have 165 psi and it would run on alcohol. Cam overlap is the key here, just as you could have a 15:1 engine and 107* of overlap and still have 165 psi cylinder pressure, at cranking.


Ramcharger,
Comp made the custom cam for me. Just under $300.00 for the cam and needs a spring with 170 lbs. @ 1.550. My springs are 130 @ 1.62 and 300 open.
 
Another thing that most overlook is the second ring gap, and especially with the pistons with a chamber or machined combustion gas space between the top and second rings. If the second ring is tighter than the top ring (gap) then the compressed gases can and will lift the top ring off the cylinder wall and cause the top ring to become unseated from the cylinder wall and piston. Virtually dropping cylinder pressure down. This is why gas port pistons are so popular in good bracket race engines. They use combustion gases and pressures to seal the top rings to the cylinder and pistons. But these rings are a good bit more money as are the pistons that use them.
 
BJR Racing said:
We run 1/8 mile here and I have a 5200 PTC converter and a 5.43 gear with 29.9 X 10.5 tires. The little engine needs all the help that it can get.
Click to expand...

What do you think it would do quarter mile?

Obviously might need to change the rear end,but how
do you think shed go?

An how much did it cost you to build if you dont mind me asking,
or charge to build somehting like that?
 
nemesis,
The engine should run mid 11's on pump gas. As a rule of thumb 7.50 = 11.50 in a car that works like it should. Yep the gear would have to drop to a 4.56 or a 4.88. But this would be determined by how much the car weigh's, a heavier car would use the higher numercial and a lighter car the lower numercial gear.

The cost of this engine was about 3K a year ago so it would more than likely be about $3,500.00 now. Or a bit more. This would be using your engine parts, crank,rods,heads, etc., etc.
 
BJR Racing said:
Ramcharger,
Comp made the custom cam for me. Just under $300.00 for the cam and needs a spring with 170 lbs. @ 1.550. My springs are 130 @ 1.62 and 300 open.
Click to expand...

Thank you.

BJR Racing said:
This is why gas port pistons are so popular in good bracket race engines. They use combustion gases and pressures to seal the top rings to the cylinder and pistons. But these rings are a good bit more money as are the pistons that use them.
Click to expand...

IIRC, the KB hyperutectics I installed in my last 360 build had gas ports between the first and second rings. They were relatively reasonably priced too. Just food for thought.
 
Were they the KB107's? If so I don't think that they have the ports. But they do have a compression chamber thats machined and solid no ports.
 
BJR Racing said:
nemesis,
The engine should run mid 11's on pump gas. As a rule of thumb 7.50 = 11.50 in a car that works like it should. Yep the gear would have to drop to a 4.56 or a 4.88. But this would be determined by how much the car weigh's, a heavier car would use the higher numercial and a lighter car the lower numercial gear.

The cost of this engine was about 3K a year ago so it would more than likely be about $3,500.00 now. Or a bit more.
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Sounds good!
I just looked at your site.

You build your own engines hey?
Not just head work?

Man if i lived in the states,youd have my business for sure.

Im lucky enough to have an awesome mechanic here.
If it wasnt for him,id prob wouldnt have my charger cuz i wouldnt
trust anyone with it!

He has 360,not stroked,just bored 30 thou,ported J heads, solid cam
with 630 odd lift if i remember right, 11.3.1 comp,he keeps swappin
em when he races so i dunno if he has a 750 or 950 demon,runs
on pump fuel, full exhaust system, weighs 1650 kilos, 9 inch ,31 spline
axles with 4.3 gears, 5000 stall,

does 10.7 at 124mph.

To me,thats impressive.
 
BJR Racing said:
Were they the KB107's? If so I don't think that they have the ports. But they do have a compression chamber thats machined and solid no ports.
Click to expand...

Let me check on that......

You are correct! I just took a look at a pic I had and it has the machined compression chamber but no gas relief, just the drainback holes behind the oil ring lands.
 
nemesis said:
Sounds good!
I just looked at your site.

You build your own engines hey?
Not just head work?

Man if i lived in the states,youd have my business for sure.

Im lucky enough to have an awesome mechanic here.
If it wasnt for him,id prob wouldnt have my charger cuz i wouldnt
trust anyone with it!

He has 360,not stroked,just bored 30 thou,ported J heads, solid cam
with 630 odd lift if i remember right, 11.3.1 comp,he keeps swappin
em when he races so i dunno if he has a 750 or 950 demon,runs
on pump fuel, full exhaust system, weighs 1650 kilos, 9 inch ,31 spline
axles with 4.3 gears, 5000 stall,

does 10.7 at 124mph.

To me,thats impressive.
Click to expand...

Where are you from? As your zip code doesn't compute here.

I did a engine for a friend of mine in TX. about 6 years ago it too was a 360 .030 and with a bad carb and in the worst air conditions that you can imagine it still ran 10.88 @ 126 @ 3,200 lbs. but it had a small roller cam like .550 lift and 240-250 duration @ .050. It had KB107 pistons and a set of W-5 heads.
 
BJR Racing said:
Where are you from? As your zip code doesn't compute here.

I did a engine for a friend of mine in TX. about 6 years ago it too was a 360 .030 and with a bad carb and in the worst air conditions that you can imagine it still ran 10.88 @ 126 @ 3,200 lbs. but it had a small roller cam like .550 lift and 240-250 duration @ .050. It had KB107 pistons and a set of W-5 heads.
Click to expand...

Yeh there good heads those w5!
**** all over J heads lol.


Im looking forward to hes next build,360 to 408 with w2's an a bigger
cam im guessing.

Im from australia my fellow mopar brotheren!
 
BJR...I am curious as to what engine you are running in that car that you have in your avatar...I am having doughts that it has a 318 cuz the front end is coming off the ground, unless of course you built a serious 318 that can kick some serious @$$...I also wanted to ask your opinion about building a streetable 318 that can have an honest 325-350HP at the rear wheels...in your opinion, will the 360 heads work or what heads do you recommend?...and to make it challenging, maybe keep the carb no bigger then 650cfm as I think it can be done...I want a honest daily driver, not one that will foul the plugs at lower rpm's and be a pest to keep tuned.

So I will offer some stipulations as to assist a decent build for around $2500 and the owner does his own porting and gasket matching...besides the pistons and cam choice and intake combo I believe a true 318 machine can be built to have torque and HP.

I would also like to hear your input about roller cams...stock VS aftermarket roller and need more info about this custom profile hydraulic tappet cam you mentioned earlier...your background and experience will be helpful to all 318 builders...and what cam would you recommend to get the required HP I'm looking for?...this thread seems to be popular at the moment, so you have a lot of others interested as well...thank you BJR:clock:
 
Well, the car in the avatar is a copy of a 383 in a 400 block, it has 0 deck piston and a .480H comp cams cam. It also has a set of hooker 2" primary tube hedders, the springs are stock HP units and the heads are a set of 452's gasket matched and bowl blended. The rest of the engine is factory stock, I did have a factory dual plane 383 RR intake that was modified, and gasket matched. I had a 750 carb and a 4500 converter and a 4.86 gear. This picture was from 2001.

As for the 318 with the power that you want go to the 322 thread as it will make more than what you want.

As for the heads on a 318 you would be backing up on the street with a 360 head. Use a 318/302 head and use the factory intake valve and use the 67-69 340 exhaust valves.

First without a flow bench your at a loss, as for the home builder your at the mercy of what whoever tells you and you have to figure out which way you really need to go. If your not oriented in porting then DON'T DO IT as you'll be backing up. I don't mean this sarcastic but if you don't have the experience 9 of 10 times the heads won't work, or will have to be reworked to get the results and hoprfully they won't be too far ported. I don't mean this to be discuraging but just being honest. It took me 5-8 years before I really had the hang of what I was doing to a set of heads and to make power. Then when I bought my flow bench I really learned what worked and what didn't.

As for the cams and rollers in general and for street use I've never really thought about it. Most of the engines that I do with rollers are race engines. They make so many good designs now for street and with hyd. lifters why would anyone want a solid roller? Hyd. rollers have there limits, can they make the power that your looking for,..........sure, but with a $2,500.00 limit the cam and lifters are going to take most of the build, besides the machining.

IMO I would opt for a good Hyd. or a small mechanical but the mechanical will require fully adjustable valve train, but then I would use the adjustable on the hyd also. The cam that I'm using is a race only unit that I had custom ground, it needs compression and stroke to really make it work and thats what I did. This cam is not even close to being streetable, but I didn't intend for the engine to go there either. For a good street engine I would do this and you should have the power that your looking for.

Use a 318 block get a set of 85-89 pistons and square deck the block to clean. Balance the componets and use the 302 heads. Gasket match them to 360 ports on the intake(the 302's can be done without welding) eariler versions will need to be welded at the pushrod pinch. Use a K6901 cam from summit and a set of adjustable rockers and the appropriate pushrods. A set of good street hedders and a RPM intake and a 650 holley carb and you should have what your looking for.
 
BJR Racing As for the 318 with the power that you want go to the 322 thread as it will make more than what you want. [COLOR=Green said:
Not sure I understand what you mean BJR
[/color]
As for the heads on a 318 you would be backing up on the street with a 360 head. Use a 318/302 head and use the factory intake valve and use the 67-69 340 exhaust valves.

In what year and make did Dodge make a 302?
First without a flow bench your at a loss, as for the home builder your at the mercy of what whoever tells you and you have to figure out which way you really need to go. If your not oriented in porting then DON'T DO IT as you'll be backing up. I don't mean this sarcastic but if you don't have the experience 9 of 10 times the heads won't work, or will have to be reworked to get the results and hoprfully they won't be too far ported. I don't mean this to be discuraging but just being honest. It took me 5-8 years before I really had the hang of what I was doing to a set of heads and to make power. Then when I bought my flow bench I really learned what worked and what didn't.

Thanks for the input, I will port match and just remove the rough casting then...that alone should help a lot.
As for the cams and rollers in general and for street use I've never really thought about it. Most of the engines that I do with rollers are race engines. They make so many good designs now for street and with hyd. lifters why would anyone want a solid roller? Hyd. rollers have there limits, can they make the power that your looking for,..........sure, but with a $2,500.00 limit the cam and lifters are going to take most of the build, besides the machining.

IMO I would opt for a good Hyd. or a small mechanical but the mechanical will require fully adjustable valve train, but then I would use the adjustable on the hyd also. The cam that I'm using is a race only unit that I had custom ground, it needs compression and stroke to really make it work and thats what I did. This cam is not even close to being streetable, but I didn't intend for the engine to go there either. For a good street engine I would do this and you should have the power that your looking for.

Use a 318 block get a set of 85-89 pistons and square deck the block to clean. Balance the componets and use the 302 heads. Gasket match them to 360 ports on the intake(the 302's can be done without welding) eariler versions will need to be welded at the pushrod pinch. Use a K6901 cam from summit and a set of adjustable rockers and the appropriate pushrods. A set of good street hedders and a RPM intake and a 650 holley carb and you should have what your looking for.
Click to expand...

I don't know much about the 302 heads...what I do know is the 360 J heads sport some good sized intake ports...so I assume that the 302 head is in between my existing 318 head and the 360 J design?...I do know that torque is made with a smaller valve and carb set up and if you go past the limit of no return, you could end up with a wimpy engine in the bottom end...so the 2.02/1.60 valve combo is too big for a 318?...what is so special about the 67-69 340 exhaust valves?
Thanx8)
 
nemesis said:
Im from australia my fellow mopar brotheren!
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Glad to have you over here from so far away. You should put your location under your name. Theres a small gaggle of fellas on your side of the ocean here.
 
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