What carb?

Author
Discussion

vodkakid

Original Poster:

1,076 posts

279 months

Sunday 31st January 2010
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Hi i have a weber downdraft on a 1293 stage 2 engine. Im looking to tune the car a bit more with a better head and maybe some other bits. I was wondering if i should change the carb because of the tuning limits of the downdraft and if so what to?

GingerWizard

4,721 posts

205 months

Monday 1st February 2010
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vodkakid said:
Hi i have a weber downdraft on a 1293 stage 2 engine. Im looking to tune the car a bit more with a better head and maybe some other bits. I was wondering if i should change the carb because of the tuning limits of the downdraft and if so what to?
details man!!! Details! nothing can be answered without the aforementioned....

DanGT

753 posts

233 months

Monday 1st February 2010
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Are you happy to modify the bulck head to fit a carb in?

Tangent Police

3,097 posts

183 months

Monday 1st February 2010
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I'd put it on SU's (1.5's) which will give you a bit of scope to play with the cam/head more, before you jump into hacking your dash up for a sidedraught.

1.5's will do most stuff, until you're looking at bigger capacities and really nth degree tuning. IMO.

That's what I reckon. Get a manifold and then build your own set out of Riley 1.5 carbs or similar.....if you're on a budget.

vodkakid

Original Poster:

1,076 posts

279 months

Monday 1st February 2010
quotequote all
Hi, I don't really want to cut the bulkhead so i think a weber sidedraft is out. As far as i know the engine is a 1293 minisport kit, with the weber. The other details I do not know. I did have it rolling roaded along time ago and it had 84bhp(97mph top speed). It's having a rebuild soon and fancied changing the head for a morspeed st3 item, maybe a cam and carbs too.
Im after a constant increase in power. Don't want to lose top end speed. Sorry if this doesn't make much sense bit of a numpty hense my question. What other details would you need?
Thanks for any help.. Budget is approx 2k including rebuild.



Edited by vodkakid on Monday 1st February 20:17

Tangent Police

3,097 posts

183 months

Tuesday 2nd February 2010
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vodkakid said:
Hi, I don't really want to cut the bulkhead so i think a weber sidedraft is out. As far as i know the engine is a 1293 minisport kit, with the weber. The other details I do not know. I did have it rolling roaded along time ago and it had 84bhp(97mph top speed). It's having a rebuild soon and fancied changing the head for a morspeed st3 item, maybe a cam and carbs too.
Im after a constant increase in power. Don't want to lose top end speed. Sorry if this doesn't make much sense bit of a numpty hense my question. What other details would you need?
Thanks for any help.. Budget is approx 2k including rebuild.
Budget is £2k. How about a supercharger sucking through a 1/3/4" SU?

You have 2 (cheapish) choices. Either a Toyota SC14 whiny but compact blower or a BMW mini one. It would be doable and offer a lot of power everywhere. If you start camming/porting an 84hp 1293 more, you're going to start losing the bottom end and then you'll want closer gears.....and everything will get more highly strung.

A supercharger will make a 1300 feel like a 1800. You have the added bonus that the positive pressure also reduces oil consumption/smoke. If you stick with a relatively sensible camshaft, it'll be fine on the helical (spread) gears. If you have an A+ gearbox with far apart ratios, the welly and spread of power will give you a good pull in all gears and maybe, would even pull a taller final drive.

I'd go for a blower. Plenty of ways of doing it on turbominis.co.uk

DanGT

753 posts

233 months

Tuesday 2nd February 2010
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You could go for an HIF44 su carb but you would not see much if any more power. A good set of twin SU's is the way I would go.

Cooperman

4,428 posts

257 months

Tuesday 2nd February 2010
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Personally I would go for twin HS4 SU's, but would ty to find a better inlet manifold than the BMC one.

vodkakid

Original Poster:

1,076 posts

279 months

Tuesday 2nd February 2010
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Would love a supercharger and have been looking at kits. Can anyone recommend a good one? Plus I would need the head machined and a center strap fitted?

Cooperman

4,428 posts

257 months

Wednesday 3rd February 2010
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I did some work on a Sprite with a Shorrock blower a while back and that has always been regarded as the traditional blower for an A-series.
I also rebuilt an engine for a Turbo Mini which had been incorretly built by a so-called 'expert' and it blew up after 4 miles from intial stert-up. I found that the geometrical compression ratio wa 10.3:1 which gave almost 15:1 at 7 psi boost, and all with ordinary Hepolite pistons and the distributor was a standard one which gave too much advance too soon.
It had to be rebuilt with Omega pistons and a geometric CR of 8:1 plus a specially curved Aldon dizzy. The combustion chambers had to be enlarged by about 2.5 cc each. I had a turbo expert set the max boost to 6.5 psi and supply a document confirming that he had done this.
It doesn't half go now!

annodomini2

6,912 posts

258 months

Wednesday 3rd February 2010
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Cooperman said:
I did some work on a Sprite with a Shorrock blower a while back and that has always been regarded as the traditional blower for an A-series.
I also rebuilt an engine for a Turbo Mini which had been incorretly built by a so-called 'expert' and it blew up after 4 miles from intial stert-up. I found that the geometrical compression ratio wa 10.3:1 which gave almost 15:1 at 7 psi boost, and all with ordinary Hepolite pistons and the distributor was a standard one which gave too much advance too soon.
It had to be rebuilt with Omega pistons and a geometric CR of 8:1 plus a specially curved Aldon dizzy. The combustion chambers had to be enlarged by about 2.5 cc each. I had a turbo expert set the max boost to 6.5 psi and supply a document confirming that he had done this.
It doesn't half go now!
Sounds like someone who typically knew nothing and had a fast road 1293 setup, came across a t3 off a metro turbo and just bolted on assuming everything was ok.

vodkakid

Original Poster:

1,076 posts

279 months

Wednesday 3rd February 2010
quotequote all
annodomini2 said:
Cooperman said:
I did some work on a Sprite with a Shorrock blower a while back and that has always been regarded as the traditional blower for an A-series.
I also rebuilt an engine for a Turbo Mini which had been incorretly built by a so-called 'expert' and it blew up after 4 miles from intial stert-up. I found that the geometrical compression ratio wa 10.3:1 which gave almost 15:1 at 7 psi boost, and all with ordinary Hepolite pistons and the distributor was a standard one which gave too much advance too soon.
It had to be rebuilt with Omega pistons and a geometric CR of 8:1 plus a specially curved Aldon dizzy. The combustion chambers had to be enlarged by about 2.5 cc each. I had a turbo expert set the max boost to 6.5 psi and supply a document confirming that he had done this.
It doesn't half go now!
Sounds like someone who typically knew nothing and had a fast road 1293 setup, came across a t3 off a metro turbo and just bolted on assuming everything was ok.
That's what i don't want to be like. Anyboby used Jon speed or Vmax scart as they do kits

vodkakid

Original Poster:

1,076 posts

279 months

Friday 5th February 2010
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I also need someone that can rebuild my engine ready for the charger (center main strap etc). Anybody know of someone?? (Located in Luton_

300bhp/ton

41,030 posts

197 months

Friday 5th February 2010
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I can't really offer much more than what has been said already. All I can say is don't use PTS in Luton.

vodkakid

Original Poster:

1,076 posts

279 months

Friday 5th February 2010
quotequote all
300bhp/ton said:
I can't really offer much more than what has been said already. All I can say is don't use PTS in Luton.
Is PTS the rolling road place off Dallow Rd

300bhp/ton

41,030 posts

197 months

Friday 5th February 2010
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vodkakid said:
300bhp/ton said:
I can't really offer much more than what has been said already. All I can say is don't use PTS in Luton.
Is PTS the rolling road place off Dallow Rd
yep.

I had heard bad things about them for a long time. But after installing some new bits on my V8 I needed it RR'd as soon as. And I didn't know anywhere else to go, so I thought sod it, I'll give it a go.

Wish I hadn't. Bunch of muppets rolleyes

I admit this was a few years ago, think 2005. So maybe its different now.

speedymadr6

14 posts

216 months

Saturday 6th February 2010
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If you want to keep original then would go twin 1 1/4's over 1/2's, we had a 1380 with 1/4's on and it produced a lot torque down the bottom when we switched to 1/2's we did gain more top end but lost some of the low down pull. Now we run a 1310 with sw10 cam, head etc with the 1/2's which suit the engine well but have thought about going back down to 1/4's again. The smaller carb can pull the air into the engine better which will produce more torque low down, yes we will loose some top end but it isn't really that much nad will make the car a bit more driveable.

Tangent Police

3,097 posts

183 months

Saturday 6th February 2010
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A HIF44 seemed to strangle my "40DCOE" 1340/286

Vizards carb graph selection is quite a handy thing smile

AlleyCat

811 posts

178 months

Wednesday 17th February 2010
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for the SuperCharger kit i would recommend VmaxScart, as for the engine rebuild, i would say to get in touch with AVR-Technologies! i dont have the number to hand but they have had some ads in MiniWorld recently.

i currently have a supercharger kit on order from Vmax bounce

Tangent Police

3,097 posts

183 months

Wednesday 17th February 2010
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There are cheaper ways of doing the same thing. Although I gather VMax are the best.