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(Post Link) post #1 of 58 Old 16-10-07 Thread Starter
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Engine work

What are the best things to do to my 1.7 8v engine to give it some more power? like bore it out or different cams or forged pistons etc. i don't want to spend fortunes just yet but i want to make it quicker
please help

EDIT: its a 1990 series 2 carb engine.

Last edited by Alex_Alfa33; 16-10-07 at 23:19.
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Re: Engine work

Is it the ie or carbs?

If it's the carbs, then a rebalance of carbs, or new filters and a rebuild would do some good.. depending on how much your willing to spend, new webbers or dellortoes might be a good idea.. Obviously if your budget is good, go for new cams and shafts, you could always go look on AH Motorsports just coz they're cool..

if its an injection.. try modding the ecu, there is autodelta, but i think they only do things for the 16v?? new exhaust systems are reletevly cheap, might make it 'sound' faster haha

try Gazzala Racing a new site if just found which has some great prices for shafts.. and exhaust systems.

hope i helped a little...

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Re: Engine work

whatever you do DON'T try Gazzella. I ordered a CSC exhaust manifold for my car in October 2006 and I'm still waiting.....Their communication is not existent, they tell you fibs all the time so you'll hang on, they never answer the phone and rarely return your calls. I'm currently pursuing them for a refund which may take some time and may require me to send the heavies in!!! Don't be fooled by their website, it all looks impressive but they are rubbish (and I'm not the only one who has had problems)

As for the engine, you could try cams (try www.colombo-bariani.com - an Italian cam company) or probably your cheapest option is to ditch the 8v and drop a 16v engine in - an extra 20 bhp for about £200 (plus a bit of work)
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Re: Engine work

Replace hydraulic tappets with mechanical ones and fit aftermarket cams. I think that Colombo & Bariani has a kit for both cams & tappets.

Replace the std straight-pipe manifold with an ANSA-like crossover one. There are several threads here where crossover manifolds are discussed, do a search with the keywords "crossover manifold".

Compression is low on the 1.7 8V (about 9.5:1 I think) so you could also replace pistons with forged ones with higher compression.

All this will probably cost you much more than a 16V engine but if you really want to keep the carbs it will require some innovative engineering. I'm on the process of doing this on my Sud so maybe I can help.

"Black holes are where God divided by zero." - Steven Wright
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Re: Engine work

[QUOTE=dickyb;1334516]whatever you do DON'T try Gazzella. I ordered a CSC exhaust manifold for my car in October 2006 and I'm still waiting.....Their communication is not existent, they tell you fibs all the time so you'll hang on, they never answer the phone and rarely return your calls. I'm currently pursuing them for a refund which may take some time and may require me to send the heavies in!!! Don't be fooled by their website, it all looks impressive but they are rubbish (and I'm not the only one who has had problems)

Oh dear, i'm sorry about saying to try there... I didn't know any people had trouble with them. Whoops..

Still though AH motorsports are good...

The 16v idea would be a good one.. why not wqork on the engine while its out of the car, replacing the injection with some nice carbs... (over-run... mmmm), then just repleacing the engine when you have time and money?

i'd do that.. but then again i want a rwd 33.. a gtv6.. or maybe a v6 75....
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Re: Engine work

Let us know what you find out?
or how you get on as i have a 1.7 8v to put in my Sud, which may benefit from a "tune-up" before it goes in...
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Re: Engine work

Wasn't there a guy on here a few months back that was having problems putting the power down in his 33? If memory serves he had the ports polished and new cams. he lost a lot of the drivability though.

Keep us posted on what you come up with!
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Re: Engine work

one of the cheapest and easiest ways to get increased power from a 1.7 is to take a 16v engine block and put a pair of 8v heads on it. The slightly domed piston of the 16v gives an increased compression of about 11 to 1... iv got one ready in the shed to do, am going to refresh the engine with new bearings etc. The heads iv got have been gas flowed... it'll be interesting to see what hp i get out of it...

col
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Re: Engine work

Do the heads bolt straight on? Be interesting to hear from anyone else who's tried this.
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Re: Engine work

yep they bolt straight on, and the 16v block is the strongest too with an extra oil feed to the crank... only thing you have to do is fit an electric fuel pump and pressure regulator...
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Re: Engine work

iv also been told that alfasud 1.5 cloverleaf cams are slightly lumpier than 1.7 cams... so to go with 1.7 mechanical heads with 1.5 cloverleaf cams should get the best results... Mind you am not sure how accurate this info is... but looking at that site mentioned above a pair of fast road cams are only £300 anyway
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Re: Engine work

Cheers for all the replies guys.

What I've decided to do 1st is get a set of fast road cams, I can get mine re-profiled for £120.
Also if I've got hydraulic tappets then ill be changing them to solid ones and ill get the ports ground n polished.
Then I'll make my own exhaust system with a crossover manifold, 1 or 2 silencers and 2 tail pipes, 1 either side or 2 either side, haven't decided yet.

What would be the best diameter of pipe to use for my exhaust system?
I think I read somewhere that the exhaust on an 8v is 42mm and people were saying to use the exhaust from a 16v which is 50mm, which would increase performance/gas flow. correct me if I'm wrong.
So would 50mm be ideal?


Last edited by Alex_Alfa33; 19-10-07 at 23:28.
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Re: Engine work

Quote:
Originally Posted by sudboy1490 View Post
the 16v block is the strongest too with an extra oil feed to the crank... only thing you have to do is fit an electric fuel pump and pressure regulator...
If you are referring to oil injection on the bottom of the pistons I think that only 145/146 blocks had that. 33 blocks didn't.

Quote:
Originally Posted by Alex_Alfa33 View Post
What would be the best diameter of pipe to use for my exhaust system?
I think I read somewhere that the exhaust on an 8v is 42mm and people were saying to use the exhaust from a 16v which is 50mm, which would increase performance/gas flow. correct me if I'm wrong.
So would 50mm be ideal?
Yep, the numbers are correct.

I've combined the crossover manifold with the 50mm exhaust from a 33 16V with very good results. Others with modified 16V engines have gone up to 60mm.
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Re: Engine work

Quote:
Originally Posted by sudboy1490 View Post
one of the cheapest and easiest ways to get increased power from a 1.7 is to take a 16v engine block and put a pair of 8v heads on it. The slightly domed piston of the 16v gives an increased compression of about 11 to 1... iv got one ready in the shed to do, am going to refresh the engine with new bearings etc. The heads iv got have been gas flowed... it'll be interesting to see what hp i get out of it...

col
Quote:
Originally Posted by sudboy1490 View Post
yep they bolt straight on, and the 16v block is the strongest too with an extra oil feed to the crank... only thing you have to do is fit an electric fuel pump and pressure regulator...
Where would i fond out more info on this..?

My 33 16v is still sitting in a garage.. could do some engine work before i get it going.
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Re: Engine work

Alex

i think markgq4 will back me up on this,just drop a 16v in there,then play with the engine.that's what i did!!

regards john
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(Post Link) post #16 of 58 Old 22-10-07 Thread Starter
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Re: Engine work

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Originally Posted by johnboy View Post
Alex

i think markgq4 will back me up on this,just drop a 16v in there,then play with the engine.that's what i did!!

regards john
Well what i want to do, is lightly tune my 8v, drive that about for a while until i can afford the insurance n source a decent 16v n then rebuild and tune that. then when the 16v is finished, ill put it in my car. then I'm going to buy a sud n stick my tuned 8v in that, race prep it n take it to track days.

how easy is it to put a 16v in replace of an 8v?
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Re: Engine work

So if the 16v block with 8v heads are used then the carbs stay and perhaps can be jetted for better perfomance ...
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Re: Engine work

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Originally Posted by johnboy View Post
Alex

i think markgq4 will back me up on this,just drop a 16v in there,then play with the engine.that's what i did!!

regards john
what he said.




the 16v is a cracking engine.. if you get one. 137bhp before you touch it.
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Re: Engine work

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137bhp before you touch it.
yeah thats what drove me towards the 16v. i got to spend a couple hundred £ on my 8v to get to that bhp.
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Re: Engine work

Quote:
Originally Posted by Alex_Alfa33 View Post
yeah thats what drove me towards the 16v. i got to spend a couple hundred £ on my 8v to get to that bhp.

Hi Alex

£100 got me a hole car.plus the car had tarox disks and braided holes,which was a bit of a tuch

if you go for the 16v which you should.all you will need is engine wiring loom crossmember.that's about it.i did mine on my mates drive.but now i have a garage thank god

regards john p.s are going to spa2008
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Re: Engine work

We are doing the same with a 16v block and 8V ported heads for our sud track car - the swap to 16v heads would put us in a different class. This is following the bottom end of our 8V enging eating itself a bit after one thrust washer wore and the other then dropped out.
One thing we are looking hard at is if you put 8V heads with a high lift cam on a 16v bottom end then piston to valve clearance clearance is an issue. Our current (knackered) bottom end has max oversize 16v pistons with pockets machined into the tops of the pistons for the (big) valves to come down into so we think we need to do the same to the new 16v bottom end we have.
One question - does anybody know how well balanced a standard 16v bottom end is ? Our original engine was fully balanced but not sure if this is worth the expense.
James
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Re: Engine work

Quote:
Originally Posted by James&Nick View Post
One question - does anybody know how well balanced a standard 16v bottom end is ? Our original engine was fully balanced but not sure if this is worth the expense.
James
when i did my P4 i weighed the pistons/rods etc and there was around 20g difference from the lightest to heaviest.
So i would guess, the answer is not that well,
on the other hand it is a VERY free-reving engine...
<shrug>

if noone here knows, try here:
http://www.alfa-pages.co.uk/phpBB3/index.php
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Re: Engine work

I went to see a cylinder head specialist today with a worn camshaft and some lifters from my old 1.7 8v motor. He looked at them and said it would be best to buy new ones (they're trashed), and that I should go for a stage 1 / mild cam and a 'lick off' the heads to increase compression by a small/safe amount.

Colombo and Bariani's website only lists a "Road max" (as opposed to "Road medium") cam for the 1.5 / 1.7 8v motor with mechanical tappets.
Catlogue here: http://www.colombo-bariani.com/catalogo.php?lang=eng
Could I use this with hydraulic tappets?
Or is the "145/146 8v 1700 P.I." cam the correct one for the hydraulic tappet motor? Its specs are completely different to the equivalent 33 mechanical tappet cam.
Can I get new mechanical tappets and stick them into the hydraulic tappet heads with no worrying that the valves will be the wrong length etc? (this is secret information nobody is willing to divulge)
Are there any other sources for road cams I should consider?

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Originally Posted by 73GTVJim
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Re: Engine work

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Can I get new mechanical tappets and stick them into the hydraulic tappet heads with no worrying that the valves will be the wrong length etc? (this is secret information nobody is willing to divulge)
Thats the bit i cant find out either....
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(Post Link) post #25 of 58 Old 24-10-07 Thread Starter
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Re: Engine work

Quote:
Originally Posted by Ben_NZ View Post
Can I get new mechanical tappets and stick them into the hydraulic tappet heads with no worrying that the valves will be the wrong length etc? (this is secret information nobody is willing to divulge)
Surely you just use shims to space it out?
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