Why do you have RONA on a 5 gallon bucket ?

RONA was Canadian hardware chain bought up by Lowes.

Beat me too it lol.77-79 Volare’s and Aspens in stock are very competitive with the 318-4, same heads and intake as the 360

I think most of the confusion comes from early and late model engines.

IMHO no 318 came with a small port 4v intake, they all got 360 heads 1.88/1.60 vales and the large port 360 4v intake which is a spredbore flange.

yes you can use a 360 4v intake on small port heads I just say result vary but is always an improvement. factory 4v 318s are the best.

what I think many misunderstand on this is the small port head which was 273 & hipo 273 first then1967 LA318 2v head. mopar did have a 4v small port intake. the IIRC 65 yr was an odd intake bolt angle. they were small port/low rise/single plane intake with a 4-hole square flange. 2v 273 had a 2v intake and the runners all looked similar in X shape/low rise single plane compared to later duel plane runner layouts.

so IMHO a early 273 4v intake is what is needed to best fit the late model small port 318 heads.

this is why I run a 273 4v intake on my small port 318 heads

or run a HOLEY STREET DOMINATOR that has small ports and runner layout like the 273 hipo

or a edelbrock LD4B with small runners/port size FYI which is a reverse copy of the larger edelbrock LD340

35 yrs of wrenching and swapping 2v to 4v on daily drivers I have found the smaller port intakes work much better with small ports heads but are just maxing the flow of the small vales.

when using the 360 heads 188/160 valves large port intake it just has more breathing capabilitys and makes for a more fun street engine.

but I have had good results with a small port intake going on a large port head. which this will also work and will help keep port velocity up going into larger head/valve ports.

I have had a couple LA318s 2v small valve/port heads running a stock 273hipo solid lift cam/rockers(.500 lift) with a 273 low rise single plane intake passing it off as a 273 in a 68 dart 4 speed 4.10 SG 26" tire.

what made it impressive to me was it was a high reving screamer on the streets for daily driving and mucho fun to drive.

"Gran" Fury. Sorry, I had to.

(IMHO no 318 came with a small port 4v intake, they all got 360 heads 1.88/1.60 vales and the large port 360 4v intake which is a spredbore flange.)
Correct

I just sold a 4bbl spread bore intake with a 1980 casting date that had small ports. I do not have the casting number, but I remember looking up the numbers and it said 360-318 engines. I too thought that all small block spread bore intakes had large ports, but this is not the case for some early 80's small block engines. I wish I had written down the casting number because I thought it was strange that they used a small port intake on a 360. When I bought the manifold, I did so because I wanted to use it on a 273 I had. I just sold the 273 and intake 3 days ago.

they do make the best 318s to transplant into something else. they are rated @177HP over the 3182v @150HP

IIRC the one I got from you Larry was 89 318 4v from a Gran Fury. that's what is in my 85 stepside at the moment. swapped it over to a whiplash roller cam/lifters, rpm air-gap 625cfm afb, headers 727-3.23 with .2.5 duels & muffs it is a little screamer now. very fun to drive in traffic.

Yes Mike, it was an '88 Gran Fury AHB "S" Code VIN and "ELE" fender tag so factory HD 318 with 360 heads, intake and exhaust manifolds.

I have always heard that putting 360 heads on a 318 to run a 4bbl intake resulted in a compression ratio drop due to the difference in the 318 and 360 head chamber size.

Some even claim that the compression ratio drop nearly negates the advantage of the 4bbl carb.

Is this correct? And did Mopar address that when producing the 318 4bbl?

No 4-bbl 318LA, how comes, but yes in a Poly 318ci, classed as a lowPO motor for some strange reason?

Then you can get an 8-BBL for a 318ci Poly lowPO motor and an 8-BBL for a piddly 273ci...

True, simple look at the FSM will bear that out.



I think the compression drop helped meet the NOX emissions requirement because I seem to recall there was a time in CA where you could not get a 2bbl 318 in the M bodies at least. Hard to find a good source of info but it seems the factory 318 4bbl had about 255 more HP and 5 more ft/lbs of torque. But I'd like to see the dyno sheets since torque is so close HP has to be too. Might be one of those we picked a number rather than max numbers.



Address what? Other than the intake, carb and head swap there rest of the 318 was pretty much the same as any other 318. Cam was the same broomstick not even sure if the ignition curve was optimized for performance rather than fuel economy or emissions as by then it was pretty much all lean burn and computer controlled. Of course my experience was towards the end of the 318 4bbl time frame not the beginning.

I know the compression on the 318-2 in the 80's was 9.0 and the 318-4 was 8.4. I've owned both and I know the seat in the pants difference is HUGE. Maybe a lot of it is the sound from the Thermoquad through '84 then Quadrajet, but the S code ELE's sure feel much stronger. And that's back when Chrysler added copious amounts of beefed up internals to their Police engines, unlike today where they just add external coolers.

Factory 2.9 rear gears, no more cats, air pump gone and heads plugged, and very easily break the wheels loose. I know, big deal, but it makes it more fun.

The casting # on the intake I had was 4173915, casting date was 3-26-81. Says they were used on 78-80 360's and 78-83 318 4bbl's. This manifold has 7/8 x 2 inch ports while most of the other spread bore intakes had 1 x 2 3/16 ports. Three years ago I went through trying to ID this manifold on here.

it was 85 up 318s got a comp bump to the 9.0 to 1 with a taller piston comp height and the closed swirl port chamber #302 heads. from the few police 85-up 4v318 engines I owned, I found they had the 9.0 to 1 piston comp height but the open chamber 360 heads drops it down almost a full point of comp. what is really different is the cams the 4v 318 use to maximize the 360 head flow.

so if you take a 2v 318 with the #302 heads 9.0 to 1 comp ratio and drop on a set of 360 heads/intake it does 2 things. 1 it drop comp ratio, 2 it still has a whimpy 2v cam with less than .400" lift

THIS is why most people say it kills effort. and say it sucks.

IMHO this is why a whiplash cam does so well in a low comp engine and works well in a street engine.

the early intake closing build cyl pressure so it does not kill off torque.

the larger valves/runners and high lift flows more in the upper rpm range. these 2 things alone make up any loss from the swap in over all performance you really feel in the seat of the pants in traffic.

example... if a stock 360 head max flow is around .450 lift any cam with more than a .450 lift is a waste as you can not get the max flow of cam due to head restriction.

so the right cam is KEY to swapping 360 heads/intake onto a lopo 318 remember though it is easy to over cam a 318 as well. so pick a high lift & short Dur @ .050 cam like the whiplash line of cams.

look at a 340 cam sheet .420/.443 lift range with x heads. so lift is right around max flow of the heads. THEN add some cubic inch & 10.5 comp with a 6-pac 4 speed 3.91sg and it becomes a high rpm legend on the streets. yes I remember in 68 when 340 A-bodys ruled the streets.

another reason I have always used a 340 cam in most 318 with the smaller heads. makes a fun daily driver. but I am hooked on the whiplash roller cams now and cant wait to run my 5.9 magnum whiplash roller cam in my home ported, back cut, #302 heads on a backward piston 318 next.

Yea, folks are really confused over this stuff.

This guy says, pay me $1500 for my cop car intake and carb.

https://www.ebay.com/itm/LAST-CALL-AS-I-WILL-NOT-RELIST-1978-79-LIL-RED-EXPRESS-COP-CAR-E58-INTAKE-CARB/173844514001?hash=item2879f0c4d1:g:skIAAOSwb2hcktUn


But then here is the intake with the PN mentioned above for a semi fair $200.

https://www.ebay.com/itm/80-Dodge-St-Regis-Plymouth-Fury-360-Police-Manifold-4173915-3-Date-Code-5-2-80/174543816769?epid=6037070795&hash=item28a39f4841:g:8rwAAOSwCxtfyMhK

here : https://www.ebay.com/itm/LAST-CALL-...SS-COP-CAR-E58-INTAKE-CARB/173844514001?

and here :
https://www.ebay.com/itm/80-Dodge-S...4173915-3-Date-Code-5-2-80/174543816769?

i don't have the numbers in front of me but it seems like that $1,500 ebay guy is banking on his parts being from a lil red express.

Stock cam in a 2bbl or 4bbl 318 was the same during the flat tappet era. The stock cam in a 360 was barely over .400" lift anyway. Even when they went roller the cam specs didn't really change much between the roller 2bbl's and the flat tappet 4bbl 318's. A few more degrees intake duration was about it. Lift and exhaust duration were the same but your point about the 340 cam is well taken. For the money it's probably the best option out there. basically any 318 needs a different cam from stock to wake it up.

Heck I bought the whole truck for $1500