Holden Sunbird power ups...

[savage1987]

My girlfriend is looking into buying a 1978 Sunbird (4cyl Torana basically)...
I understand they make a dismal amount of power from the factory (60kw). What sort of power gains are there to be had from simple and cheap modifications??? Living in the hills a 60rwhp car really isn't ideal...

Any ideas let me know!!

Any info appreciated,
Cheers
Sam

[Boonz]

lol.... well shave the head for higher compression... advance the timing about 4 degrees... run premium and thats about it

its basically a 6 cylinder with 2 cylinders chopped off the front

[savage1987]

Just on that one.. how do you tell the difference between the Opel 1900 and the Starfire four?? The 1978 models came out with both... The Starfire four is the cut down 6 you're referring to... a motor with a bad reputation, apparently.

How much power do you get from the above mods?? Roughly, of course, not expecting a figure within 2hp lol; and how easy is it to shave the heads?

Sam

[Sami]

I've read about someone who's gotten their sunbird's engine ported and polished and had a "double throat webber carby"... that sounds impressive. Is it though? (I'm a bit of a novice here)

[commsirac]

The starfire motor will look exactly like a six cylinder red motor with two cylinders chopped off and is blue.......ive never seen the opel to describe it though. I believe that the code is L16 for the opel and L18 for the starfire, which is found on the vehicle's details plate on the left of the plenum chamber under the bonnet. On the motor itself the starfire will have a serial number starting with UN, whereas the opel will be UA.

I wouldnt be bothered spending any money trying to make it go faster, it will keep up with traffic and go up hills. It would be more sensible to actually buy a six cylinder then spend three to four hundred dollars minimum doing cylinder head mods to the four that probably wont achieve much anyway.
Buying a four and converting to a six, thats costly, youll need to buy a 2nd hand six and a different diff and have it all fitted.

These cars are going to feel slow regardless compared to the 145kW one has on tap on a typical v6.

[Sami]

I'm the one looking at the car btw
I would get the six, but to cut a long story short, I've been given $4000 to go towards a 4-cyl and a 4-cyl ONLY. Not my rules, obviously, but there you go. I'm entirely aware that it would be more sensible to get the 6 but thats not possible so we're just curious to know what IS possible with a 4.

Sounds sad but power is pretty important as it'll be a difficult transition from the newer commodores I'm used to, to a 60kw 4-cyl. I just want to bring it up to scratch.

[Clutchy]

I'm the one looking at the car btw
I would get the six, but to cut a long story short, I've been given $4000 to go towards a 4-cyl and a 4-cyl ONLY. Not my rules, obviously, but there you go. I'm entirely aware that it would be more sensible to get the 6 but thats not possible so we're just curious to know what IS possible with a 4.

Sounds sad but power is pretty important as it'll be a difficult transition from the newer commodores I'm used to, to a 60kw 4-cyl. I just want to bring it up to scratch.

Buy a barina or something like that over a sunbird unless ya can put a 6 in it as the four cylinder(missfire) dont have a good word to be said about them apart from the rods. why aint you allowed to get a 6 ?

[savage1987]

LOL missfire... are they that bad!?

[Sami]

My mum (the one giving me the money) lives smack-bang in the centre of paris and therefore can't possibly see why anyone would need anything more than a 4-cyl, let alone a P-Plater. I can't really get a barina though... I've spent a lot of time paying out chicks in barinas so if i got one I really would have to hit myself. And laugh at my own car.

[commsirac]

Okay then, whatever the reasons. A mint sunbird would possibly cost $2-3000, and that'll leave you at least $1000 for the engine mods........still cant help you as I cant see the basics such as porting/polishing extractors getting you more than a couple of kW. They already have a very good (forgotten the name, its not a strombery) carby fitted(the starfire)(much better than the 6) and changing it would be unlikely to achieve anything either

[Clutchy]

Okay then, whatever the reasons. A mint sunbird would possibly cost $2-3000, and that'll leave you at least $1000 for the engine mods........still cant help you as I cant see the basics such as porting/polishing extractors getting you more than a couple of kW. They already have a very good (forgotten the name, its not a strombery) carby fitted(the starfire)(much better than the 6) and changing it would be unlikely to achieve anything either

Ya mean the stromberg(spelling) mate ? they were on the 6 cylinder aswell mate hate to tell ya.

[Clutchy]

My mum (the one giving me the money) lives smack-bang in the centre of paris and therefore can't possibly see why anyone would need anything more than a 4-cyl, let alone a P-Plater. I can't really get a barina though... I've spent a lot of time paying out chicks in barinas so if i got one I really would have to hit myself. And laugh at my own car.

So will ya mum ever see the car ? just put a six in it its not hard to do just change the cross member to a 6 cylinder one not sure on the diff think they had the banjo in them and off ya go (I had a uc sunbird with a 179 in it and its the best car ive ever had)

[Sami]

omg what a hopeless cause. Looking at a mint sunbird for 2 grand so I've certainly got some room for improvement but if there's not much improvement to be had it won't be worth it. I don't like my alternative though... probably something riced and turbo-ed.

[commsirac]

Ya mean the stromberg(spelling) mate ? they were on the 6 cylinder aswell mate hate to tell ya.

Yes, stromberg(typo). Hate to tell ya, but you cant read. I said its not the Stromberg, which is what every basic six cylinder holden had up to that time. Its just come to me(the name), the starfire got the twin barrel rochester varajet, quite a sophisticated unit. Also afaik the cross member for the starfire is exactly the same as for the 6cyl, just the opel was different. They all had salisburys differentials, the 78's were the UCs, the sunbirds had 3.9 final drives whereas the sixes had either 2.78, 3.08 or 3.35

[m62vpute]

A Barina or a Swift would have been my sugestion, i know they are a bit of a girly car but if you get a 5 speed manual you will be suprised on how nice they drive and handle compared to the 4 cylinder sunbirds (my girlfriend has a coupe swift)


You can pick up a 1992 to 1995 model for about $2500 to $3000 in good nick

[Sami]

So will ya mum ever see the car ? just put a six in it its not hard to do just change the cross member to a 6 cylinder one not sure on the diff think they had the banjo in them and off ya go (I had a uc sunbird with a 179 in it and its the best car ive ever had)

Ok so assuming dropping in a six is a pretty easy way to go, how easy would it be to actually find one that isn't in desperate need of a rebuild, or find one at all?

The girly ones aren't really my thing... I'd rather forget about the $4000 and save up for a HJ Premier to do up if those were my only other choices .

THanks for all the advice btw

[commsirac]

have a look on ebay for recently rebuilt 202s, should be able to pick up a fairly worked motor for less than a grand. A decent rebuild with a few mods is going to cost at least $1500 if you get it done yourself. You could take your chances with just a second hand stock 6 thats come out of a wreck etc for a $100 or so too.
One hassle you are going to have is if you are going to get it roadworthy. It depends on who gives you the roadworthy, its unlikely youll pick up a motor that will have all the emission control stuff fitted to it which is necessary to meet adr27A for a 78 model. Probably best to get it roadworthied with the four, then swap the motor,,,,though the reg authorities still may want to see it to record the engine number themselves....dont know in your state. Also factor in that you are going to have to do a diff/rear axle changeover.......possibly another $4-500, trans......if its behind an opel motor the trans wont bolt up to a 6 either, bellhousing has to be changed as well as possibly the tailshaft.
Perhaps also visit gmh-torana.com and get some opinions there too.

[Sami]

Oh wow, awesome advice thanks for that! Getting a car over the pits won't be a problem. If we can get a HK Monaro with a 4/71 supercharger over the pits, we can get this roadworthied

[Clutchy]

Yes, stromberg(typo). Hate to tell ya, but you cant read. I said its not the Stromberg, which is what every basic six cylinder holden had up to that time. Its just come to me(the name), the starfire got the twin barrel rochester varajet, quite a sophisticated unit. Also afaik the cross member for the starfire is exactly the same as for the 6cyl, just the opel was different. They all had salisburys differentials, the 78's were the UCs, the sunbirds had 3.9 final drives whereas the sixes had either 2.78, 3.08 or 3.35

Only going of my car mate with the cross member had to change it 4 the 6 it had the 6 in it wen i got it but had the mounts changed to suit the 6 and it had a banjo diff in it aswell. and the varajet is the worst carby ever made mate.

[commsirac]

Only going of my car mate with the cross member had to change it 4 the 6 it had the 6 in it wen i got it but had the mounts changed to suit the 6 and it had a banjo diff in it aswell. and the varajet is the worst carby ever made mate.

That's great.....why not say that when you post rather than pretend to say it applies to all and sundry.
Possibly you had the opel motor where the mounts have to be changed.....I think I mentioned all that. As for a banjo in a UC, maybe the opel came with them too as a left over from the last model,however, one of the selling features of the UC was an all new diff, rts etc. The varajet one of the worst carbies everymade, you are talking specifically about the one on the starfire......I dont know, just reporting that it was far more a sophisticated unit that must have been included for a reason..........and Im not your mate.

[Blown V6 Hatch]

As far as i know all UC's run Salisburys! Clutchy, are you sure you didn't have an LX sunbird??? They run Banjos.

As Commsirac said, if it has the starfire engine in it, it will be a much simpler conversion to a 6 because the front end is identical but, if it has the opel (which is a heap of junk, 100 times worse than the starfire) then you will have to change crossmember. As has been said, the diffs are the same throughout the UC model, however the ratios are different for the 4 cylinder and would make the 6 cylinder rev its arse off at 100 k's. So you will need to change diff too, but they are fairly cheap nowadays. What you need to get is a complete 6 cylinder motor & auto (or manual) and drop it in. That would be your best option as there is a lot more stuff around for them if you decide to modify it a bit later on. The problem with the 4 cylinder engines is that no one modifys them, they just turf them for a 6 or V8 (which is a good move), so there is no aftermarket parts around for them.

[blammy1]

My girlfriend is looking into buying a 1978 Sunbird (4cyl Torana basically)...
I understand they make a dismal amount of power from the factory (60kw). What sort of power gains are there to be had from simple and cheap modifications??? Living in the hills a 60rwhp car really isn't ideal...

Any ideas let me know!!

Any info appreciated,
Cheers
Sam

I had a 1979 UC Sunbird with the Starfire. I bought it for about $800-900. My brother now owns it and it is still running well.

As this motor is basically the good old 6-cylinder black/blue motor with 2 pots cut off, most of the high performance parts from the (small) six fit - just if you buy them in a set you're left with 2 spares.

So I had the cylinder head ported and fitted with big valves, unleaded seats and running Yella Terra roller rockers, chrome moly push rods, anti pump-up lifters and alloy timing gear, so now the top end will take the revs the bottom end - which is bullet proof - will handle. With this are oversized high-compression pistons (ACL race series, I think; around 10.5:1 but could have used even more - with premium petrol had no pinging whatsoever) and maybe even ARP rod bolts. Used a high-lift rapid acting Tighe cam with asymmetrical profile and a race-spec harmonic balancer. I also had a spare cam ground with an even hotter profile - Tighe's 851 grind, i think, but didn't bother installing this as it would be just too much top and and i would have lost too much mid-range and torque required for the street. In the end the cam that was installed was advanced by 2 or 3 degrees to calm it down a bit and bring teh power band a bit lower down the rev range.

Flywheel was lightened and running a lighter, higher-spec clutch and the whole bottom end was balanced. Ran the BW 5-speed VK Commodore 'box and the standard 3.9 rear end (I lined up a 3.55 ratio but never fitted it as I liked the acceleration with the 3.9).

I then got an XU-1 triple SU manifold and cut and rewelded it for only four cylinders, and was running twin SU carbs (either inch and 3/4ers, or 2 inch, I think). Spent a lot of time fiddling with the needles to get the fuel right. Ended up going back to the much-maligned Varijet (which is too big for standard motor) as I found a carb specialist (Mick - Northside Carbs?) in the northern suburbs of Brisbane (Virginia?) who really knew how to get these units working, as the SUs sucked too much fuel and were always running too rich or too lean, and had that dead-spot if you really floored it until the vacuum picked up again. Didn't loose that much power going back to the Varijet and it was much more driveable afterwards (I was going to get a Weber but this bloke was able to do such a good job on the varijet i didn't need to. About the only improvement I could think of was to get a triple Weber 6-cylinder manifold and convert this to run twin DCOEs, but didn't want to pay the extra dosh at the time as it was costing me enough anyway (in someways I wish I did, as I reckon it would have picked up another 10-15 horses or more).

Ran a set of Pacemaker (I think) headers and a 2 and 1/4 inch system with a resonator and single muffler so the sound was REALY good and you should have heard it bark and cackle on the overun!

To really top it all off I got a Crane optical conversion kit for the distributor and fiited a very high voltage ignition coil and an MSD-style CDI box (Mallory?). Got the dizzy's advance remapped (I think the vacuum advance was removed and was just mechanical) and fiited good leads and NGK plus, so it doesn't misfire at high revs. The MSD unit has an adjustable rev limited so I set this to about 7000-7500rpm as the motor would easily rev past this!

I never got the motor dyno's but it was putting out A LOT more power than the standard Starfire, probably around/at least twice as much! All i know was how good the motor sounded and how my friends couldn't believe how fast it was (plus as the whole suspension was rebuilt and polybushed, it handled to match). I also remember its rego plate - it was "253 xxx", so every one thought they were custom plates and it was running a 253 V8 !!!

This car is still running and is still a very reliable and very fast little mover. In all the years since I gave it to my brother the only thing the engine has ever required is oil changes and tune-ups of the carbs.

PS I thought I may have held the 'record' for the most powerful Starfire going until I heard about a bloke who was running one at 2.2L and had a turbo, and was supposedly putting out over 200 horses!

[Tsunamix]

Step 1 - Rip out everything in the engine bay
step 2 By A 245 Cu Hemi Inline 6 & 727 Torqueflite auto
Step 3 Tack a pair of small GT35 turbo fed from sidedraught 48IDA webers onto the intake side.
Step 4 using a VC commodore crossmember mount the whole shebang into the UC torry.
Step 5 Profit.

Seriously the unofficial name of the 4 cylinder was the BACKFIRE 4. It was 3 types of crap buried in bucket. It's not worth touching at all.

[ari666]

im pretty sure sav got banned about 6 months ago... so he prolly wont be able to hear you.

edit* WOW! that was a MASSIVE post too

[minux]

im pretty sure sav got banned about 6 months ago... so he prolly wont be able to hear you.

edit* WOW! that was a MASSIVE post too

Who banned him? Certainly no admin or mod.