Can your zook cruise at 100km/hr in top gear?

[GRPABT1]

Always wonder about this so thought I'd make a thread. Also thought it would be good to help people choose a setup for their needs.

Post your model, engine , gearing and tyre combos. And a blurb about it's cruising manners.

Model: 1988 Sierra WT SWB Ute chop

Engine combo: 1988 MK1 GTi swift 1.3, Uni filter panel with snorkel, extractors, 2inch press bent exhaust with high flow cat and straight through muffler, Crane coil and eagle leads.

Gearing: Stock 3.7 diffs, 6.5 trail gear transfer gears, stock 5 speed.

Tyres: 31X10.5X15 simex extreme trekker's

Mine cruises at 100km/hr with about 3/4 throttle on a bad day (headwind) and most days will sit on 110km/hr with less than half throttle. Hills can require full throttle but usually doesn't loose speed or require dropping back a gear.

[brendan_h]

1.6 efi vit motor extractors and snorkel. 32x11.5. stage 1 rockoppers (12% in high)

can cruise at 100 easy. can get to 110 and prob cruise there but havent tryed. hills depends on size usualy drop it bac into 4th and can cruise at 110 up them

[Gwagensteve]

660cc F6A SOHC, 12lb peak boost, 2.25" exhaust, FMIC, stock inlet/airbox

TT 6.5 transfer

5.12 diffs

9/34 16 swampers.

LWB, WT diffs, alloy tray, steel bar, light exo.

It will cruise at 100kph on level ground in 5th with load at about 5-8psi of boost. I guess about 2/3 throttle, 4300ish rpm.

decent acceleration requires 4th and full throttle- about 5000rpm.

it will fall back on hills, but even big hills with heavy load will be taken at about 6000rpm in 3rd - about 80kph of road speed.

Swampers on 4.5" rims don't like 100kph in any case.

I have more tuning to do and would like about 20% more torque. Should be achievable with a little bit more turbo flow.

Steve.

[DavePatrol]

96 coily hard top, standed 1.3 5 speed with extracters and 2inch strait thru exhourst with hi flow muffler, got 235/75r15 tyers with stock gearing
can cruse at 100ks in fith 1/2 to 3/4 throtle can do more if i tried, for hills dont no yet havent come across any big ones that need 4th yet

cheers scottt

[alien]

92 WT, g16a with weber 32/36 -> extractors and 2" pipe (with cat). SPOA on 31x10.5r15 muddies on 15x7's and 5.14 tcase gears.

Throttle would be about 1/4 to 1/2 way down in 5th at 100k's doing 3400rpm. Unaffected by head and tail wind (well of course it is, but only minor).

In this configuration i've done 130km/hr no worries with tons to spare - but as the tyres are only speed rated to 120 i didnt dare push and harder. Didnt take long at all to reach 120... probably about 300m and my foot wasnt flat...

[neil_se]

91 WT, standard 1.3 with extractors and exhaust, 31s, 3.9 diffs, S1 Rockhoppers

Foot flat to the floor in 5th it eventually gets to 100 (up to 110 on a downslope) but no chance uphill.

[BlueSuzy]

91 wt swb

Baleno 1.6,full 2" zorst include extractors, cat

33x12.5, 6.5 trailgears stock diffs 3.7

Can cruise @ 130 prob half throttle. Headwind 110...full

Only light front and rear bars.. Overall not much more weight in suzy then stock..

Mostly in 5th at 110kms any freeway hill unless slow people muck up the constant speed that the motor is sitting at..(like in right lane doin 80kms)

[Kitika]

94 wt softop swb

Fresh rebuilt 1.3, 2 inch exhaust with extractors

235/85 R16, 6.5 trail gears, stocko diffs

It sits on about 100km/h most the time but likes to stay at about 90.
I do have a 3k carby which I think is probably a little small but I have a stock carby in the shed to try out again. I have a bullbar, sliders and rear swing away bar which does add up in weight plus heavy tyres and rims.

I don't like going to fast in the zook crosswinds are too scary!

[Moph]

In this configuration i've done 130km/hr no worries with tons to spare ... Didnt take long at all to reach 120... probably about 300m and my foot wasnt flat...

I should've done a 1.6 conversion Just took my freshly rebuilt 1.3L out for a run, 400 k's on the clock, and with foot flat but shifting at 5500rpm I hit only 90kph at the 300m mark and 120kph took a full kay!

Model: 1993 Sierra WT SWB hard top

Engine: Freshly rebuilt G13BA, had done 296,000 before rebuild. Air box currently sucking air from the engine bay as my dogs chewed the tube leading to the guard. Stock 1.5" exhaust, cat and muffler. Stock coil and Topgun leads. Stock carby, freshly overhauled.

Gearing: Stock 3.7 diffs, stock transfer, stock 5 speed

Tyres: 235/75R15 Goodyear Wrangler MTR's on 15x7's

On the flat it cruises very happily at 100kph in 5th doing 3100rpm. Throttle is about 1/3 down, but there's not much left in the remaining 2/3 ... likely due to gearing being too high? Can handle a gentle incline with full throttle but with anything that would normally be classed as a 'hill' I either stay in 5th and slow to 90kph, or shift back to 4th to keep 100kph.

Just went up Willunga Hill tonight which is a couple of kays long and 9% average gradient. Had to shift back to third to maintain speed, and sat on 70kph doing around 4000rpm. Don't want to load the engine up too much at the moment and it felt comfortable at 4000rpm.

Haven't hit a strong headwind with the rebuilt motor yet, but prior to rebuild a strong headwind could bring cruising speed down to 90kph.

[jazuki]

87 nt tin top

Nissian 1.5 with a SC12 supercharger ,SU carb ,Extractors with a 2inch exaust and turbo muffler,standard engine internal running about 6psi ,2.5inch air intake inside.

Stock diffs , stock transfer and 5 speed

30x9.5x15 maxxis buckshots

Cruises at 100 kmh at about 1/2 to 3/4 throttle ,for hills and passing just put you foot down and it takes off , heaps better than my old worn out GA13 and alot safer when it comes to passing .

[ajsr]

not a hope in hell
6.5 reduction
32 mongrels
spoa
dead stock 1300 no exhaust(STOCK)
lucky to get 105-110 flat to the boards on flat road
1st to 2nd gear on a good up hill

[Highway-Star]

'92 SWB WT
standard G13B
extractors and 2" exhaust
4.9 TC gears
3.7 diffs

31x10.5R15 Simex Centipede MT's: 100km/h is easy in 5th, only reasonable grade hills require change down.

31x10.5x15 Silverstone Extreme's: 100km/h is essentially impossible in 5th gear, 4th is not a problem, but holds 100 easily in 4th even on steep hills.

205/75R15 Firestone ASR's: 100km/h, wish I had 6th gear .

[matsmad]

We got a 1993 soft top with g16a, K&N filter, extractors, 2" zaust, 3" lift and 30" all terrains. Drove to brissy couple weekends ago sat on 120kph in 5th with a/c on and about 1/2 - 3/4 throttle. Don't think there was much wind tho.

[alien]

In this configuration i've done 130km/hr no worries with tons to spare ... Didnt take long at all to reach 120... probably about 300m and my foot wasnt flat...

I should've done a 1.6 conversion Just took my freshly rebuilt 1.3L out for a run, 400 k's on the clock, and with foot flat but shifting at 5500rpm I hit only 90kph at the 300m mark and 120kph took a full kay!

I've found with mine, putting my foot flat floods slightly, but gradually accelerating will give better results... might be worth trying =)

[ofr57]

flogged stock motor with stock exhaust, 6.4's + 3.9r&p does 100 on about half throttle and i would say 3/4 on hills this is running 31 x 10.5 mtr's on 8 inch rims

[joeblow]

yep, mine does.

[GRPABT1]

yep, mine does.

There goes joe with the great tech again

[GRPABT1]

flogged stock motor with stock exhaust, 6.4's + 3.9r&p does 100 on about half throttle and i would say 3/4 on hills this is running 31 x 10.5 mtr's on 8 inch rims

I'm thinking 3.9 r&p would be perfect gearing for me. I might just add a turbo instead though

[jonno_racing]

mine is a STOCK 1.3 coily with 30's.. bought it like that..
Just hold 100kph.. bit slower on hills

[zookimal]

Depends on the wind.

31s, 6.5s, 3.7s, G13ba.

Some days it feels good, other days it feels painfully slow and 100 is a struggle. When it had a weber on it sat on 100 happily, but it wasn't worth keeping it on the motor.

[ofr57]

flogged stock motor with stock exhaust, 6.4's + 3.9r&p does 100 on about half throttle and i would say 3/4 on hills this is running 31 x 10.5 mtr's on 8 inch rims

I'm thinking 3.9 r&p would be perfect gearing for me. I might just add a turbo instead though

i would go the gears .. myself thinking on going up again to 4. something yukon sell them

[joeblow]

1.6 efi, standard t/case gearing, 5.1 diffs, auto, 33's, does 100 without breaking a sweat.....not to mention what it was clocked at top speed. oh, and she's 1500 kg's.

[nicbeer]

tintop

1.6 mpfi, 3.9s, extractors and 2" system, std transfer
31s
std manual

easy 100 or 110.

1200kg

[MART]

Soft top

4.8 r&p.
Stage 4 gears.
G13A , 1.3 , TBI , supercharged.
35 inch tyres.
100 on flat , 1/3 throttle
100 on hills , 1/2 to 3/4 throttle
1650 kg

Cheers Paul.

[Kitika]

I should've done a 1.6 conversion Crying or Very sad Just took my freshly rebuilt 1.3L out for a run, 400 k's on the clock, and with foot flat but shifting at 5500rpm I hit only 90kph at the 300m mark and 120kph took a full kay!

If your motor has only done 400kms it'll still be way to tight to get any performance out of it. You'll have to wait about 3000to5000k's till she'll be broken in. Also I wouldn't be given it such a hard time revving it to 5500 and racing it etc can be detrimental to it's longevity.

[St Jimmy]

I should've done a 1.6 conversion Crying or Very sad Just took my freshly rebuilt 1.3L out for a run, 400 k's on the clock, and with foot flat but shifting at 5500rpm I hit only 90kph at the 300m mark and 120kph took a full kay!

If your motor has only done 400kms it'll still be way to tight to get any performance out of it. You'll have to wait about 3000to5000k's till she'll be broken in. Also I wouldn't be given it such a hard time revving it to 5500 and racing it etc can be detrimental to it's longevity.

So have you buit a motor before i built mine and from day 1 kept the rev's around 3500 to 6000. All the time the only thing that has let me down is the Weber carb, but you get that and mine sits on 100kph when the carb is running ok btw it's a 1.3 60tho off the head 2nd over size pistons hand seated/lapped valves, balanced crank .soon to fit 4 carbs off a yammi thou jetted to suit

[Kitika]

Yes I did rebuild my motor about 6000k's ago and it is running sweet as now. It did take a fair few k's for everything to seat and wear in. I had the crank reground, oversized pistons, valves done, head shaved and all that and it goes way better than it ever did.

[St Jimmy]

Yes I did rebuild my motor about 6000k's ago and it is running sweet as now. It did take a fair few k's for everything to seat and wear in. I had the crank reground, oversized pistons, valves done, head shaved and all that and it goes way better than it ever did.

sorry to imply that you didn't know what you were doing.
regards
james

[Kitika]

That's alright mate! Now we'll just have see who's rebuilt motor lasts the longest!

[Moph]

Also I wouldn't be given it such a hard time revving it to 5500 and racing it etc can be detrimental to it's longevity.

Kikita, if you ask 10 mechanics what the best procedure for breaking an engine in is you'll probably receive 9 different answers. I spent many hours researching it on the web and asked a couple of mechanic friends, and the procedure that made the most sense to me was the following:

After rebuild, bores have a cross-hatch pattern on them as a result of the honing process. The treatment of a rebuilt engine over the first couple of hundred k's will largely determine how well the rings and cylinder wear in and mate. Keeping the revs too low during the first couple of hundred k's, or keeping revs too constant (ie long country runs), can result in the bores glazing before this mating process has completed. This will result in an imperfect seal and long-term blow-by of oil / loss of compression / loss of performance.

The best way to ensure that the cylinder wall doesn't glaze before wearing in has occurred is to keep revs medium - high over the first couple of hundred k's, starting at say 3500rpm for first couple of k's, then 4000rpm max for 20 k's, then 4500rpm max for 50 k's, etc, gradually stepping up to redline over time, but keeping load low. I'm only taking it to 5500rpm at the moment after 400k's and will be stepping it up to 6000rpm max tomorrow after I've done an oil and filter change.

I've been keeping revs up but load light. So driving to work in the morning, I hold each gear thru to current max revs under light acceleration rather than changing at around 3500 rpm'ish as normal, and then when I'm up to speed I alternate between 3rd and 4th and wander up and down in speed a bit if I haven't got anyone on my tail rather than just sit in 4th at 60.

It's a refinement on the old 'drive it like you stole it' break-in technique, but avoids high side wall loads on the cylinder walls that will occur if you have high loads. For this reason too it's important to avoid lugging the engine.

As I say, there's many opinions out there as to what's the best way to break an engine in. I'm not looking to criticise how anyone else chooses to break their engine in - this just seems to me to make the most sense, and on that basis it's how I've chosen to break mine in.