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Spyderman
Alfasud
Joined: 04 Sep 2003
Posts: 48
Location: Hampshire
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 Posted: Sat Dec 11, 2004 3:51 pm Post subject: Tuning 1.7 16v's |
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Hi Guys
This may or may not seem an odd question to ask but at what point does tuning the 16v become expensive.
The perspective I am coming from is that I am looking to fit a 1.7 16v into my kit car to replace the 1.5 Sud Sprint lump in it currently.
Eventually I would like to supercharge the 16v as well, but for immediate use I would just use a unsupercharged 16v.
How much more power on external mods to the standard engine can you get.
Thinking like a chip change, air filters, exhaust etc. Not looking at Carb conversions or aftermarket throttle bodies etc. An aftermarket remapable ECU would be OK as I could use that later with a new map.
Once it gets into the realms of pulling engines apart etc for cams, that is when the supercharging becomes more viable..
Cheers Guy |
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LDA
Alfa 33
Joined: 28 Nov 2004
Posts: 276
Location: France
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| Posted: Sat Dec 11, 2004 6:40 pm Post subject: |
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i'm no expert but i'll fill you in on what i think i know.
137bhp (non cat) from the stock lump.
filter will give you a couple of bhp.
exhaust could give you another 5-8ish bhp
a stand alone ecu with rolling road setup will be the best upgrade.
adjustable fuel presure regulator to help out.
i would think you could get around 155-160ish bhp from the above mods and a bit more if you added the cams.
you should see over 180bhp with low presure supercharger on there. i would put an intercooler in there aswell as some colder plugs.
cams are about 800quid plus drive wheels at around 200quid, not a chaep uprade. 4 bloody cams 
electric ignition rather than dizzy driven is good for helping the power too.
apart from that your looking at rebuilds with low comp pistons and steel gaskets etc. the stock throttle bodies are not too bad and are not really worth dumping unless you want race car power from your lump.
good luck with the project, any pics?
L.
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| Posted: Sat Dec 11, 2004 7:47 pm Post subject: |
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Cheers LDA
155-160 should be ok for shifting around 725kg of car for a while 
http://brookespeed.v21hosting.co.uk
Looking at the price of some of the chips they just seem too expensive now, a replacement mappable ECU's are not a great deal more.
Actually think less !
Would be looking at Rotrex centrifugal blower, nice and small and very efficient. Helped a mate fit one to his 4.2v8 landie. Currently puts out 307bhp/312lbs torque without an intercooler. The Rotrex puts out upto about 14psi
Would probably lower the compression in the 16v motor using a compression plate. Don't think could be bothered with cams. Just build a strong motor and up the boost. |
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Spyderman
Alfasud
Joined: 04 Sep 2003
Posts: 48
Location: Hampshire
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| Posted: Sat Dec 11, 2004 7:52 pm Post subject: |
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| Dunno why that happened my username didnt appear in my reply just showed as guest |
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1.7
Guest
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| Posted: Thu Dec 16, 2004 5:07 pm Post subject: 16v |
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spider man.....supercharging your engine is gonna probably blow the crap out of your gearbox....looking at your web-site pics, I suspect your either using a beetle or Renault gearbox????......I think you will find a standard 16v engine with an aftermarket ECU (Emeraly are good value at £500, with a good reputation) on standard throttle bodies, without the upper spider, fit some nice trumpets above the lower throttle body assemblies, with a decent exhaust, will be quite enough for 150 to 160 Bhp, so you will easily be able to shred your tyres and scare the crap out of yourself.......this is the exact route I intend to take with my Fugitive, I reckon it could all be built and mapped for around £1,000
Raising the compression ratio will also cost you peanuts if you do it yourself, all you need to do it make up some over size idler/tensioner wheels, in order to take up the extra cam belt slack
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Spyderman
Alfasud
Joined: 04 Sep 2003
Posts: 48
Location: Hampshire
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| Posted: Sat Dec 18, 2004 8:11 pm Post subject: |
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I use a Alfa 5 speed in it currently, It has previously had a VW beetle engine box in it.
If I go to supercharge it I may use a VW buggy box from the US
and adapt to it.
A loss of 1 gear but a stronger box. |
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LDA
Alfa 33
Joined: 28 Nov 2004
Posts: 276
Location: France
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| Posted: Sat Dec 18, 2004 9:04 pm Post subject: Re: 16v |
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| 1.7 wrote: |
Raising the compression ratio will also cost you peanuts if you do it yourself, all you need to do it make up some over size idler/tensioner wheels, in order to take up the extra cam belt slack
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this mod works? cool i thought that i needed to get thinner head gaskets or skim the heads.
how much bigger do the wheels need to be?
L.
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paddy granger
Alfa Sprint
Joined: 12 Aug 2003
Posts: 248
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| Posted: Sun Dec 19, 2004 2:54 pm Post subject: Re: 16v |
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| LDA wrote: |
| 1.7 wrote: |
Raising the compression ratio will also cost you peanuts if you do it yourself, all you need to do it make up some over size idler/tensioner wheels, in order to take up the extra cam belt slack
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this mod works? cool i thought that i needed to get thinner head gaskets or skim the heads.
how much bigger do the wheels need to be?
L. |
I think he is refering to a modification after the block has been skimmed, which will make the cambelt slack. The distance bewteen the crank and the cams reduces the more you skin the heads. In order to tighten the cambelts up, the bigger wheels are needed.
P. |
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Spyderman
Alfasud
Joined: 04 Sep 2003
Posts: 48
Location: Hampshire
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| Posted: Sun Dec 19, 2004 4:41 pm Post subject: |
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| On side to my intial question , how much more does the 16v weigh than a equivalent 8v |
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LDA
Alfa 33
Joined: 28 Nov 2004
Posts: 276
Location: France
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| Posted: Mon Dec 20, 2004 1:00 pm Post subject: Re: 16v |
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| paddy granger wrote: |
| LDA wrote: |
| 1.7 wrote: |
Raising the compression ratio will also cost you peanuts if you do it yourself, all you need to do it make up some over size idler/tensioner wheels, in order to take up the extra cam belt slack
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this mod works? cool i thought that i needed to get thinner head gaskets or skim the heads.
how much bigger do the wheels need to be?
L. |
I think he is refering to a modification after the block has been skimmed, which will make the cambelt slack. The distance bewteen the crank and the cams reduces the more you skin the heads. In order to tighten the cambelts up, the bigger wheels are needed.
P. |
ah that makes much more sence 
L.
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knight
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| Posted: Wed Jan 05, 2005 6:18 pm Post subject: weight difference??? |
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did anyone ever find out the weight difference between the 1.7 8v and 1.7 16v?......the reason I ask Is coz my engine is hanging out the rear on a beetle gearbox.....currently fitted with a 1.5 sud motor......I suspect the 16v motor is a fair bit heavier than the 8v engines.......but by how much.....no guesses please  |
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Spyderman
Alfasud
Joined: 04 Sep 2003
Posts: 48
Location: Hampshire
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| Posted: Sat Jan 08, 2005 1:52 pm Post subject: |
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Hi Knight not sure how much it weighs more myself it would nice to know.
Can tell you that the Alfa flat four is 40lbs heavier than the VW motor
http://home.att.net/~marksmoore/Weights.htm
Measured the weight of an Alfa 1.5sprint lump a couple of years ago and the quoted figure on this website is pretty much spot on |
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