It takes just a moment to join our fantastic community
Discussion in 'Straight 6 Development And Modification' started by jake87, Jul 28, 2006.
Can anyone tell me the advantages and dis advantages with a 3.3 and a 2.85.
173 has a shorter stroke and i think smaller bore.
I remember it as being a stronger and more effcient motor than the 202.
Can anyone elaborate?
Best choice would be 202 :thumbsup:
Part wise i think you would have a way better chance of finding parts for a 202.
202 had a sizeable amount of extra torque.
173 was ridiculously better on fuel, up to 20% better in the same car (Torana/Commodore).
Both respond incredibly well to better breathing with larger gains in power, torque and especially economy with the 202.
Parts for either are easily obtainable as most are the same.
Both are hard to kill.
thanks dude, i have a blue 173 in my vh its pretty good on fuel compared to my old red 202 in the torana but still doesnt seem to have much power, could be the carb. thinkin about changin to fuel injection from a black 202 from a vk
ok seein as this is the modification section and this thread involves 173's ill ask here and other people will be able to find answers easily enough...
right now have a 83' VH 173 blue top (2.85L for those playing at home) wagon and have already whacked on a set of "advance" extractors and a 2.5" exhaust but thats it... im not scared to do any work myself and have a lot of people around to help me along... what else can i do to make it a better car all round? name it and ill consider it most probably do it
Install a better cam and perhaps a new carby (not a Holley but that's only my opinion).
I don't know the ideal specs for a cam but somebody on here will or you can enquire at any auto parts shop.
I'm old and in my younger days you could buy cams ranging from Stage 1 (mild) to Stage 5 (Racing or wild) nobody paid attention to the actual specs.
The 173 does respond very well to a cam and extractors.
If it came down to a choice for me, I'd choose the 202. Mainly for the reputation the 202 holds. I have previously owned a 202, and it was more relaible than my VN!! It had plenty of power, plus it wasn't too bad on fuel. I can't really ellaborate on the 173 though, although I have heard they are a strong and reliable motor.
But one of the best things about the Holden straight 6, is the simplicity! And it doesn't take much modification to make it a damn good and responsive engine.
straight off im really happy with the economy im getting from my car so with these 2 options in mind would a mild cam upgrade (i dont wanna go crazy here) be a noticable difference? i would love my car to have that rough lumpy sound of a bigger cam upgrade but dont wanna be able to see my fuel needle go down by the second just sitting at the lights...
with the carby upgrade do some carbies have better mixing capabilities? as in will a higher quality carby filter more air in so a leaner or better burning mixture is offered to the engine?
im slowly learning so correct me anywhere im wrong.
I'm also still learning.
I had what was called a 1/4 cam in in my 173 VH 5spd. This was supposedly 1/4 way to being a race cam (or so everyone used to say), in other words a mild cam. I had the standard Varijet carby rebuilt and Perry Headers/extractors.
The idle was lumpy enough for me to be asked quite a few times if it was an eight, at least until I gave it some revs and then there was no mistaking that it was a six.
The economy improved quite a bit and even driven with a bit more gusto I got 28mpg (10L/100km) in the city and could easily get 35+mpg on a country run.
Just with those mods my 0 - 100km/h dropped by nearly two seconds to a supercar like 9.8 seconds (that was considered good back then).
So I was happy with the standard carby and the car remained very reliable.
There are a few different carbies you can fit like Webbers, Twin or triple SUs and twin or triple Strombergs that may provide a bit more go but the strombergs and SUs will use a fair amount of fuel and need tuning every weekend.
Everyone used to fit a 350 Holley. In my opinion and from experience unless the motor is fully worked they are too big for a Holden six. People who had them fitted would get them rejetted when once they realised they got only 10mpg and had no guts. The end result was an expensive carby that offered less performance and efficiency than the standard carby. The Holley 180 was much better suited but were hard to find.
The Holley was the thing to have though so everybody got one.
The noise they made convinced many that their cars were going quicker.
Sorry for the waffleand not much help. Because I haven't looked into it for so long there may be many other good choices these days.
There will be someone here who knows.
ok sounds sweet ill definately look into getting an upgraded cam and leave my carbie alone... just play with mixture screw etc as im having a few probs at take off while cold etc... only other thing i have in mind right now is go grab some better spark leads 10 second job
It all depends wot ya want from ya 6 if ya want more performance than bolt the 173 head onto ya 202 wif a mild cam good zorst and wot ever carby ya want and a 350 aint to big 4 a 202 ya just gotta set it up rite and it will go like a cut cat or if ya want good sound wif good fuel econemy the 173 wif a little towing cam will be the way to go another thing that will come into consideration wif ya fuel eccon is wot ya gearbox is like and wot diff ratio you are running.
i have a 81 vh with extractors and a 2.2" zaust it has cai. but im putting on a weber 34adm carbie more power less fuel easire to tune, then possibly a cam i dnt want mad power just enough to satisfy me.
when you put in a lumpy cam.... you change the vacum... Hollys have changable power valves... i'm not sure about standard holden carbies... idle mixture is for a few revs... primary jet is for a few more revs... secondary jets for more revs.... power valve opens up at the top end of the rev range... also when you push the accerator flat like when passing or just flooring it...
I know the 173 also came out as a high and low compression motor as the 202 nothing wrong with eather in my opinion.
I've had several of both and good motors, i also have a 3.3 VK black ive fitted in a 79 mitzi galant with 5 spd.( my dirt track racer car.)
I really love the old 202. Havent had one in many years but used to hang out at this workshop on the weekends and they would be into building theyre "hand grenade" motors. The block was pretty standard nothing too fancy but had a nice whiney straight cut timing gear set - huge cam - hardened pushrods - heaps of headwork porting and intake (almost through to the waterjacket - some would and you chuck em) double valve springs and roller rockers bigger valves etc - elctric fuel pump into a 600! (cant quite remember but it was huge) holley doublepumper and huge fuel lines - straight out dumped 3inch exhaust - locked up "banjo" (not very strong but plentiful) diff. Made a huge noise, had heaps of power and when you snapped one axle the drive would all be on one side so that wheel would spin at will in any gear with a heavy foot. The block would last maybe a couple of weeks before it blew up but all the other parts you kept and just replace the block.
brohawk, post sum pics 4 ov vh, sounds awsome
My old 'rana used to hammer. Was a 202, 40 thou' overbore pistons, starfire rods, XU1 spec cam, 161 head, alloy straight cut timing gears (standard fibre ones are ****), extractors and single 2.25" exhaust and a 350 holley. In a light car with a all aussie used to fly.
There is a forumla to work out what carb to use.
My 202 combo works out to around 330cfm or so. The above is easy to work out except maybe the VE%. Basically a full blown drag car is around 100%, stock low performance cars (like a 173/202) are around 75-85% and something that has had some mods like better head, cam and extractors is around 85-95%.
a-team look at the my ride section there are hell pics there. none of the engine though not good enough
I have a blue HC 173, has 275,000k's on it and it still went alright. A lot of the time I abused the crap out of it. I also got the 5spd behind it so I use to do a few skids.
Off the line it use to keep up with V6's till I was at about 4k in 2nd...then they'd overtake haha.
If u were in my car while I was out thrashing it, you wouldn't think the motor was as crap as it was. It leaked oil from just about every gasket in the motor, blows blue smoke at about 3000rpm (only started doing that bout 3 months b4 I took it off the road), has noisy lifters, and overall if u look at the motor youd be surprised if it even ran at all lol.
A few months ago the VH got defected for a few things, oil on the motor being one haha....so now I've decided to rebuild the motor. I also ended up putting a 3.45 borgy under the ass end coz I blew 2 salisbury 8 bolts.
So far I've got nearly everything to start putting my motor back 2gether...just need to get some machining done and if all goes well I'll have a yella terra head to go on.
So far I've got JP Performance straight cuts to go in, Crow cam (35603 rev range is 2000-5000rpm), Hastings rings, ACL bearings, ACL MonoTorque gasket kit, new welch plugs, new lifters, and if I don't put the yella terra head on I'm getting my head shaved, acid dipped and cleaned, valve regrind and also some Crow performance valve springs.
When I pulled the motor apart, 4 of the 6 top pistons rings were broken haha.
I'm hoping for atleast 80rwkw when I'm finished.
Separate names with a comma.