David Vizard, Uncle Tony's garage, Unity motorsport. Mission impossible Dodge 302 Head porting

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MopaR&D said:
That would have been nice for us hot-rodders here 20 years later but even before the Magnum came out the only vehicles getting V-8s were trucks and SUVs. Not much benefit to having a big-port head on an engine that will rarely see over 4000 RPM and needs stump-pulling torque for doing truck things.

Yeah the 5.7L Hemi is put in trucks and they have giant head ports but those engines don't pull down low like a 5.9L Magnum does.
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THIS ^^^^ 100%! I've said it many times --The 5.7 Hemi is a poor truck engine but a great pass car engine. That's why the 8spd trans is essential. I still wish Ma Mopar back in the mid 80's had designed the Daytona's/Lasers/Chargers to be a 5.2/5.9 RWD/Manual Tranny platform to compete with the Fox Body/Camaro stuff. J.Rob
 
RAMM said:
THIS ^^^^ 100%! I've said it many times --The 5.7 Hemi is a poor truck engine but a great pass car engine. That's why the 8spd trans is essential. I still wish Ma Mopar back in the mid 80's had designed the Daytona's/Lasers/Chargers to be a 5.2/5.9 RWD/Manual Tranny platform to compete with the Fox Body/Camaro stuff. J.Rob
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If I ever get a newer Ram pickup (or look for one for my dad) with the 5.7L it'll definitely be an 8-speed with the shorter (numerically higher) axle ratio.

I wish that too but their company philosophy back then was basically "if it isn't a truck or SUV, it's FWD". First-gen LX cars are pretty cheap now but they're built with so much plastic junk, interiors look/feel super cheap and they're big and heavy, not the best for a V8 RWD hot-rod project. Ironically (or not?) the most popular "late-model" vehicles for G3 Hemi swaps are Dakota pickups.
 
MopaR&D said:
That would have been nice for us hot-rodders here 20 years later but even before the Magnum came out the only vehicles getting V-8s were trucks and SUVs. Not much benefit to having a big-port head on an engine that will rarely see over 4000 RPM and needs stump-pulling torque for doing truck things.

Yeah the 5.7L Hemi is put in trucks and they have giant head ports but those engines don't pull down low like a 5.9L Magnum does.
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All this talk of truck and passenger car engines is funny. Chrysler Australia took a "truck engine" that was designed in the US but not used because they needed a replacement for the slant 6. They needed a performance version so they sent one to Italy to have the Italians design the induction system and stuck it in a short wheel base A body and ran 14.1's in the quarter in the early 70's with a 265 ci inline 6. Not bad for a "truck engine"
 
Hysteric said:
All this talk of truck and passenger car engines is funny. Chrysler Australia took a "truck engine" that was designed in the US but not used because they needed a replacement for the slant 6. They needed a performance version so they sent one to Italy to have the Italians design the induction system and stuck it in a short wheel base A body and ran 14.1's in the quarter in the early 70's with a 265 ci inline 6. Not bad for a "truck engine"
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Not really. The Aussie "Hemi" (barely) I-6 was a full clean-sheet design engineered mostly by Chrysler Australia for passenger cars. Chrysler USA considered using a 265 stroked to 300+ ci as a truck engine but the market was too small to justify the cost of bringing it here. This is straight from "Chrysler Engines 1922-1998" written by Willem Weertman. I think they did get some consultation from Weber in Italy for designing the top-level performance version of the Hemi 6 with the triple side-drafts.

You can take a truck engine and make it reasonably powerful but it's a lot harder to take a pass car engine and modify it to make more low-end torque. Not to mention until the 1980s or so there was hardly any difference between car and truck engines from U.S. automakers.
 
Hysteric said:
All this talk of truck and passenger car engines is funny. Chrysler Australia took a "truck engine" that was designed in the US but not used because they needed a replacement for the slant 6. They needed a performance version so they sent one to Italy to have the Italians design the induction system and stuck it in a short wheel base A body and ran 14.1's in the quarter in the early 70's with a 265 ci inline 6. Not bad for a "truck engine"
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Your from Australia ? Is this why the 302 heads, aren't 360 rare overthere ?

With this truck engine thing seem like people generally like a performance engine to peak 5000-5500 rpm higher it's to racey lower it revs like a truck engine :)
 
My close-to-stock truck engine that is still in a long bed truck ran 13.08 against a head wind on it's only day to run the 1/4 mile. 125 dollar SM air gap and a small re-grind cam. We think there is a 12.9 in it pretty easy.
 
273 said:
Your from Australia ? Is this why the 302 heads, aren't 360 rare overthere ?
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Everything is hard to come by and expensive.

MopaR&D said:
Not really. The Aussie "Hemi" (barely) I-6 was a full clean-sheet design engineered mostly by Chrysler Australia for passenger cars.
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Going through what I have for the charger design and history it states that the engine was designed for light and medium commercial vehicles. Starting at 245 ci with a possible range up to 300 inches.
 
273 said:
I can imagine I live in Canada and even though we border the State it's pretty pricey here and used market is fairly small.
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Anything you buy from the US has to be flown or shipped THEN consider exchange rate differences so it becomes paramount to make do with what you have or pay through the nose. You know those heads that we made in Australia the EQ ones? Well I couldn't even buy them local as all stock went to the US and so we would need to buy them from there. What a f@#$%^ joke.
 
Hysteric said:
. You know those heads that we made in Australia the EQ ones? Well I couldn't even buy them local as all stock went to the US and so we would need to buy them from there. What a f@#$%^ joke.
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That's insane, what a piss off.
 
Hysteric said:
Anything you buy from the US has to be flown or shipped THEN consider exchange rate differences so it becomes paramount to make do with what you have or pay through the nose
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We basically pay double so i could only imagine overthere
 
Hysteric said:
Everything is hard to come by and expensive.


Going through what I have for the charger design and history it states that the engine was designed for light and medium commercial vehicles. Starting at 245 ci with a possible range up to 300 inches.
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It's possible I mixed up some facts but the book I'm referencing was written by a former Chrysler engineer who was directly involved with the design of the Slant-6, LA V-8, 426 Hemi and 2.2/2.5 4-cylinder and was a part of the engine design department when the BB wedge was being drawn up. He also coordinated with Chrysler Australia on the Hemi 6. Many of his accounts are first-hand and he became head of the engine engineering department in the 1970s iirc. I'll check again when I'm home, at work currently lol.
 
Chrysler Hemi-6 Engine - Wikipedia

Chrysler Corporation in the US had been working since 1966 on an inline 6-cylinder engine, called the D-engine, to replace the Slant 6 (G-engine) in Dodge trucks, but abandoned the effort after prototypes were built. This was Chrysler's first thin wall (lightweight) cast iron engine design. Chrysler Australia wanted a new six-cylinder engine for use in the Australian Chrysler Valiant, and so Chrysler USA sent a prototype engine to Chrysler Australia's engineers to continue developing the D-engine. The first 245 cu in (4.0 L) variant was released for the 1970 model year in the VG-model Valiant.
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Not that you can trust Wkipedia completely but maybe correct.
 
273 said:
We basically pay double so i could only imagine overthere
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Well it's $8-900 for an air gap, $1800 each for an assembled edelbrock head, MSD dizzy $700, $1500 for a rebuildable 318 core, around 5k for a running 360...you get the idea.
We used to be able to import stuff from the US cheaper than local retail prices but then the government slapped a 10% import tax on us (thats on the item AND shipping) which kinda killed it.
As for the hemi 6 - we got the blueprints and a prototype from the states, but there were a lot of changes made to the bottom end by Chrysler Australia and the original head design was scrapped and we made our own. A handfull of test engines were shipped to Italy for development of the six pack weber setup wich made 302hp@5600rpm & 325ft-lbs@4100rpm.
 
This is a great video for a beginner to watch.

 
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Bakerlite said:
This is a great video for a beginner to watch.

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That's a good video, shows a variety of porting cutting tips Charles uses and why.

Like the looks of that single plane flow design much better than the dual plane he first started his intake manifold porting on. Will be interesting to see the flow numbers on this one when he finishes up with it. Especially comparing the 2 manifold flow tests when he is done with both.

My vote goes for the single plane as the main intake for their 318 build.
 
George Jets said:
That's a good video, shows a variety of porting cutting tips Charles uses and why.

Like the looks of that single plane flow design much better than the dual plane he first started his intake manifold porting on. Will be interesting to see the flow numbers on this one when he finishes up with it. Especially comparing the 2 manifold flow tests when he is done with both.

My vote goes for the single plane as the main intake for their 318 build.
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Might as well try both but looks like single will get there easier.
 
Ted265 said:
Well it's $8-900 for an air gap, $1800 each for an assembled edelbrock head, MSD dizzy $700, $1500 for a rebuildable 318 core, around 5k for a running 360...you get the idea.
We used to be able to import stuff from the US cheaper than local retail prices but then the government slapped a 10% import tax on us (thats on the item AND shipping) which kinda killed it.
As for the hemi 6 - we got the blueprints and a prototype from the states, but there were a lot of changes made to the bottom end by Chrysler Australia and the original head design was scrapped and we made our own. A handfull of test engines were shipped to Italy for development of the six pack weber setup wich made 302hp@5600rpm & 325ft-lbs@4100rpm.
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A buddy of mine who flys over to Australia from Canada about 6 times a year just took 2 heads and an intake in his suitcase for me that I sold…the Australian who bought them said it was like a half price sale!
 
318 Single Plane Intake.
Good one to Performance Port for the 1 hp per cu.in. 318 build.

Go Like Hell, 7000 + RPM

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Here is an interesting video of an experimental transparent intake manifold to show the fuel/air mixture moving through it.

Shows what is going on inside like where Charles is doing his intake manifold internal runner cleanups.

 
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