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Vtec conversions in Sydney? And why the Toyota over vtec?
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Author:  The Scotsman [ Sat Aug 13, 2016 12:13 pm ]
Post subject:  Vtec conversions in Sydney? And why the Toyota over vtec?
Trying to work out which way to go with my mini currently,
I'm tempted by the idea of the Honda engine swap, has anyone in Sydney got one on the road?
I've looked through here and nothing has popped out, but that could also me being dozy
Also I've noticed a more common mod is the Toyota engine swap, not wanting to open a hornets nest but apart from the turbo what's the advantage?
Cheers
Author:  Kennomini [ Sat Aug 13, 2016 12:27 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
The Vtec's are a bulky and heavy engine compared to the Toyota starlet engine. Yes the vtec will make more power and has a higher BHP potential but that's here nor there.
Author:  Mr Anderson [ Tue Aug 16, 2016 4:45 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Im absolutely no expert, but the larger capacity of the vtec engine could provide some low down increase in torque, but for the additional weight/bulk on install it might not be worth it? Yes you might be able to get higher max BHP from a vtec, but I can't get the available power down from the starlet engine, so even the high power numbers you can get from a starlet engine can be spinning the wheels half way through 3rd gear, so other than bragging rights or track days on slicks, not sure the higher BHP potential is much of a draw card.

Happy to take you for a drive in my starlet mini sometime, I'm in the south of Sydney, Sutherland shire, not that far from you.
Author:  Bennjamin [ Wed Aug 17, 2016 10:40 am ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Mr Anderson wrote:
Im absolutely no expert, but the larger capacity of the vtec engine could provide some low down increase in torque, but for the additional weight/bulk on install it might not be worth it? Yes you might be able to get higher max BHP from a vtec, but I can't get the available power down from the starlet engine, so even the high power numbers you can get from a starlet engine can be spinning the wheels half way through 3rd gear, so other than bragging rights or track days on slicks, not sure the higher BHP potential is much of a draw card.

Happy to take you for a drive in my starlet mini sometime, I'm in the south of Sydney, Sutherland shire, not that far from you.



Hey mate

Gearing (both gearbox and wheel size) and what type of diff are very relevant here - also NA vs turboed too all factor it I your "wheel spins" experience.
So , what is your setup as above ?
Author:  Slugman [ Wed Aug 17, 2016 1:26 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
+1 for Bennjamins comment - Need to know the setup.
My NA B18CR has the final drive changed (3.4) to make it work with my 185/45R13 Tyres, & running it through a gearing calculator my speed vs revs are apparently similar to an Integra Type R. It drives like a dream, if your dream doesn't include air-con.
Before I changed the Fd, I couldn't use first gear at all, & was changing into 5th to cruise at 60km/hr.

That said, I still have to be careful taking off from the lights when it's dry, & have to ride the clutch when passing over the white line if it's wet. Could spin it up in gears 1 to 3 if I tried, but not much easier than the original Integra could.
Author:  Mr Anderson [ Tue Aug 23, 2016 8:20 am ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Bennjamin wrote:
Mr Anderson wrote:
Im absolutely no expert, but the larger capacity of the vtec engine could provide some low down increase in torque, but for the additional weight/bulk on install it might not be worth it? Yes you might be able to get higher max BHP from a vtec, but I can't get the available power down from the starlet engine, so even the high power numbers you can get from a starlet engine can be spinning the wheels half way through 3rd gear, so other than bragging rights or track days on slicks, not sure the higher BHP potential is much of a draw card.

Happy to take you for a drive in my starlet mini sometime, I'm in the south of Sydney, Sutherland shire, not that far from you.



Hey mate

Gearing (both gearbox and wheel size) and what type of diff are very relevant here - also NA vs turboed too all factor it I your "wheel spins" experience.

So , what is your setup as above ?


Starlet gearbox with factory open diff, 13x7 wheels, big turbo that comes on a little later than I would like... enter "wheel spins".

I had maybe incorrectly assumed the Vtec conversion was going down the turbo path, if not then I would have thought a lot to gain from going Vtec on a NA conversion.
Author:  Slugman [ Tue Aug 23, 2016 10:12 am ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
I think I see where the confusion comes in.
I plugged the gear ratios I found into the MFactory gear ratio calculator to get the max speed in any gear at 3000rpm. I used this low figure because most of the time you would be changing gears before then.
Very few people race around the streets, so 2,500rpm might be even more realistic. Apologies if the Toyota gear ratios are not correct. Anyway, assuming 3000rpm & 195/45R13 tyres;

Starlet 1=3.545 = 19km/h, 2=1.904 = 35km/h, 3=1.310 = 51km/h, 4=0.969 = 68km/h with 4.3 FD & assumed max RPM of 3000
Integra R 1=3.266 = 19km/h, 2=2.13 = 29km/h, 3=1.517 = 40km/h, 4=1.212 = 50km/h, 5=0.972 = 63km/h with 4.7 FD & assumed max RPM of 3000

Except you can get different FD's for the Integra, like I did. I got a 3.4 FD from the UK, which changes it to;
Integra R 1=3.266 = 26km/h, 2=2.13 = 40km/h, 3=1.517 = 55km/h, 4=1.212 = 69km/h, 5=0.972 = 87km/h with 3.4 FD & assumed max RPM of 3000

http://calc.teammfactory.com/index.php?tirewidth=195&tireprofile=55&wheelsize=15&tirewidth2=195&tireprofile2=55&wheelsize2=15&tirediameter1=23.44&tirediameter2=23.44&finaldrive1=4.4&finaldrive2=4.4&gearratio1=3.23&gearratio2=2.105&gearratio3=1.458&gearratio4=1.107&gearratio5=0.848&gearratio6=0&gearratioa=3.23&gearratiob=2.105&gearratioc=1.458&gearratiod=1.107&gearratioe=0.848&gearratiof=0&maxrpm1=8400&maxrpm2=8400&comparison=1&kmh=1&tranny=

TL;DR – Unmodified Integra has more grunt than Starlet, but similar-ish speed for the revs, so can’t get power down. Modified FD Integra fixes this.
Author:  Bennjamin [ Tue Aug 23, 2016 7:43 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Mr Anderson wrote:
Starlet gearbox with factory open diff, 13x7 wheels, big turbo that comes on a little later than I would like... enter "wheel spins".

I had maybe incorrectly assumed the Vtec conversion was going down the turbo path, if not then I would have thought a lot to gain from going Vtec on a NA conversion.



Ill just say that an open diff is your biggest issue. That in itself will have you bouncing and hopping towards the redline as boost comes on 8) Probably fun in the wet !
The standard starlet gt motor makes about 135hp where the 3 main honda motors in question make 160hp (b16a2) , 180ish HP ( b18c2) and 200hp (b18c7). I would bet that the starlet would be much more peaky and prone to simply spinning the tyres than a honda flatter NA motor would. The starlet motor makes all its torque at 4800rpm where the honda has to almost redline to make a touch more !
Author:  69k1100 [ Tue Aug 23, 2016 9:33 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
I see none of the usual players have entered the fray.

What do you want out of the swap? Reliability? Power? Economy?

Turbo or NA is irrelevant unless you have a goal. Why do you need a VVT OR Vtec equipped engine?

Vtec is variable valve lift, specifically the cam has two sets of intake lobes, low rpm and high rpm, to make the power band very broad.

And let's be serious 135hp is a fast road mini, 160hp is a race car. Are you planning a daily or a track warrior?

Personally I would like a daily with a nice free revving engine. . love my swift gti, the ideal mini would have a g13b at its heart. 130hp at the crank is fairly achievable with these engines and they have a great characteristic to them, and an 8500rpm red line. Can't speak for Toyota.

best part? If you're clever I reckon you could get one of these into an unmodified shell with a lightly modified subframe (5 speed for the Gti box, but a shorter 4 speed is available). 130hp and 4 gears would make a nice daily with a more modern engine.
Author:  Dutchy1978 [ Fri Sep 23, 2016 8:50 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
It will depend on if you want NA or turbo and what type of mini you want to put it in. Both will require significant body mods and a custom subframe to make it work however the Toyota and Suzuki engines have the transmission on the passenger side which works better for RHD vehicles due to the steering rack position. I have the Vtec and it is a lot of engine to get into a standard length round nose but can be done. Clearances around the engine are minimal.
Mine is going on the dyno next week to tune the ECU properly so I'm yet to feel the power. Without it tuned it still spins the front wheels and has plenty of torque steer. Personal choice in my opinion.
Author:  Kennomini [ Sat Sep 24, 2016 12:34 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
You also need to consider the power levels and what is "sensiable" for a road car. IMO 200bhp is too much for a road mini (this is from hear say not 1st hand experience). Even the guys running 160hp 1.3L minis say it's more than enough.
Same with the turbo ford boys, yes you can run 800bhp+ in them but tune the same car to 400bhp and you won't notice the difference on most race tracks and definatly not on the street.
Their is no benfit of over powering the chasie, just bragging rights and tyre smoke in 3rd...
Author:  Phil 850 [ Sat Sep 24, 2016 8:41 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Probably the biggest advantage is not the 200bhp but the torque you get with the increased capacity.
My STI has 195kW, but it's the torque at 3500 rpm that shoves down the road is the biggest thrill 8)
Author:  Dutchy1978 [ Sun Sep 25, 2016 7:48 am ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Phil 850 wrote:
Probably the biggest advantage is not the 200bhp but the torque you get with the increased capacity.
My STI has 195kW, but it's the torque at 3500 rpm that shoves down the road is the biggest thrill 8)

I agree. It's all about being thrown into the back of your seat.
Author:  fuzzy-hair-man [ Sun Sep 25, 2016 1:30 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Kennomini wrote:
You also need to consider the power levels and what is "sensiable" for a road car. IMO 200bhp is too much for a road mini (this is from hear say not 1st hand experience). Even the guys running 160hp 1.3L minis say it's more than enough.
Same with the turbo ford boys, yes you can run 800bhp+ in them but tune the same car to 400bhp and you won't notice the difference on most race tracks and definatly not on the street.
Their is no benfit of over powering the chasie, just bragging rights and tyre smoke in 3rd...


I agree, I'd also say it is the torque rather than power that causes the car to break traction in the first place, it's also torque that produces rapid acceleration, so ideally I guess you'd want enough torque for goods acceleration but not enough to constantly be breaking traction, grip will vary though so....

At the moment for my cg13de I'm thinking of getting cams and lightening the flywheel, the healthy torque means any loss of low down torque will probably just mean less wheel spin in 1st and 2nd which unless you're boasting or showing off is no bad thing. I'm probably looking at 110 to 120hp with cams, the car is easy to drive behaves itself and has less torque steer than my 1275 A series mini. Power is nice and linear with no sudden rush of power.
Author:  Speed [ Thu May 04, 2017 6:44 pm ]
Post subject:  Re: Vtec conversions in Sydney? And why the Toyota over vtec
Mr Anderson wrote:

Starlet gearbox with factory open diff, 13x7 wheels, big turbo that comes on a little later than I would like... enter "wheel spins".


A "little", now that's an understatement.
I dont recall really feeling boost until above 4k.

A smaller turbo and an LSD will make your car much more driveable.

With regards to the OP, I don't see the need to go thru the complications for the vtec when a suzuki or toyota donk already puts down the numbers where you really need them when on the street.



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