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02/05/2005 19:13:54   Rens Lensvelt   Hello Everybody.

I was just wondering.
I'm thinking about spending some money on my lovely saab 96 (duh) and i want some power in return.
Now i've heard that a 1700cc engine is basicly the same as a 1500, only bigger cylinders (and some other stuff).
But can you bore your 1500 to 1700?? or even to 1815cc??
what's the "biggest" bore for the 1500?

and then? some oversized pistons ofcourse but DO you need a new manifold or can you use your old 1500 manifold with solex carb? (i've got the 2bbl on my 1500).

but if you need a new manifold and new carb. what's the best price/hp? i don't want to spend 500 pound for 10hp. but i would want to spend a 1000 pound for 300hp. (if you catch my drift).

Already thanks for everything and plenty of greatings from a wet holland

Rens Lensvelt

 
02/05/2005 21:38:32   Senor Burt   To get 1700cc you need a different crank and pistons. You can bore out up to at least 1840cc. European Ford Taunus had this engine. Many V4's in the USA had 1700cc, but were lower compression and about the same power.
You can use the same manifold and carb, but the carb will need different jets.
A good sports exhaust will make a difference too.
Once you get past this stage and get into high compressions, sports cams.
ported heads and big valves, things start to get more expensive.  
02/05/2005 22:12:58   Rens Lensvelt   But i can take my 1500. bore it out to 1800.. fit a 1700 crank and V6 pistons.
Use the same manifold and my 2bbl solex but with different jets?

any idea how much power we are talking about?

any good places for the 1700 crank and V6 pistons?

thanks for the fast reply  
02/05/2005 22:21:00   Rens Lensvelt   ps. already got the jettex sport exhaust from Rolf from the sweden saab parts (nice guy).  
02/05/2005 23:34:49   Max   Hi Rens,
with very simple methods and little money (as for me I am a student) you can get more power out of a 1500ccm engine.

In my case I put a Weber 32/36DGV carb with a K&N airfilter fitted (80, ebay), Saab Sport and Rally camshaft (85, friend in Finland), milled the heads by 1mm this gives a comp. ratio of 10.2:1 (15, local engineering shop), ground the ports to bigger dimensions shown in Saab Sport&Rally manuals from the 70ies (free of charge, did it myself), fit a 2" sports exhaust (Jetex or Simons,200), fit an electronic ignition (Pertronix, crane cams or comparable systems, approx. 55). If we sum it up: 435.

This setup gives 95bhp proven by dyno! It's not bad to get 30bhp per 435, isn't it?

ps. ask jack ashcraft in the u.s. for the jetting or I can give the values to you if you need them.
 
03/05/2005 07:55:19   Richard   There are plenty of 1700 cranks about. As long as you stick to the 4 stud manifold you will keep the costs down. You should be able to get 120bhp from a long throw crank, ported heads with big valves and rally spec camshaft.
I would take your car to a rolling road to have the jets and chokes set as no two engines are the same. I remember some racers put richer jets in their cars if the weather was damp, just an example of how small things can effect the jet choice.  
03/05/2005 09:44:10   Rens Lensvelt   Hi,
Thx Max, sounds like a good setup and a cheap one. I've already got the sports exhaust so that saves 200euro already. so indeed 235 euro for 95bhp is really not bad.

stage1)
a weber 32/36DGV + K&N
a sport and rally camshaft
milled the head 1mm
bigger ports
electronic ignition

And here come's what richard says for stage 2.
a weber 32/36DGV + K&N
a sport and rally camshaft
milled the head 1mm
bigger ports
electronic ignition
AND THEN MORE
bore it out to 1800 (euro 250)
1700 crank (euro don't know)
should go to 120bhp?  
03/05/2005 12:24:55   Richard   I think that should fit, just check with the seller that the stud holes match the four stud manifold. They were fitted to Ford Pinto engines and you can get rebuild kits and all the jets for them.
Make sure your timing gears are in good condition and that the balance shaft bearings are ok.  
03/05/2005 12:51:30   Sonett 71   The one you found on ebay is a 32/36 DGAV. It's the same as the DGV but with an automatic choke. It's was used on the Ford Escort Mexico. But you need a flange (wich you can make in nylon) to create some extra space between the water tubes and the valve covers. This causes no trouble on a 96, (a Sonett has not enough clearance between the bonnet and the air filter).  
03/05/2005 14:01:09   Rens Lensvelt   OK. i probably found a carb closer to home. (without shipping over sea).
But i've got some troubles finding the Saab Sport and Rally camshaft, i'm trying to find a 7.2 or 7.6
Does anyone know if these are still made? or you can use these cams from an other car?
Or better, does someone have one laying around?

thx about the carb replys!!!  
03/05/2005 14:21:28   Sonett 71   Rens,

You can mail Chris Hanegreefs at the following addres: fgranada@pi.be - I think he's from Limburg near the Dutch border. He will need your old cam, I paid 163 euro for a fast street cam. He is specialized in old ford parts, so he can also help you with a 1700cc crank and some 93mm pistons from a V6.  
03/05/2005 16:52:33   Richard   I would have one re-ground out of a std cam. Kent cams do them over in the UK they are about 85. I have always found the Saab cams to have a wider power band than most of the re-ground stuff and they spin the followers. Even a 7.6 is usable on the road as long as you dont spend all your journey in a traffic jam, but you would be wise to fit stiffer v6 valve springs, a rev limiter at 6500rpm and steel timing gears (std ones will take the hammer for a while, nylon ones are better).
If you are going for 95 bhp or above I would recomend a better clutch and a reconditioned radiator with a extra row or cores. You have a couple of options here, one is to fit red springs (stiffer) to a good std spring cover plate, the other is to just have a paddle plate with cerametalic lining (or fit both), option 3 is a diaphragm convertion from highgate in the Uk.
Dont forget you can machining the flywheel down and have it rebalanced which should not cost too much, you dont have to go to the extent of the 'works' lightening.
If you want it cheap keep the power to 90 bhp give or take a bit and you will find you dont need a lot of the extra bits that add up to a fair sum. My engine cost about 2500+ in parts, but its what I wanted, I might add 3D ignition and throttle bodies at some stage, yeeeeehaaaa!  
03/05/2005 17:15:05   Rens   As I notice when you reach a certain point (about 90-95bhp) it will get expensive and you need to change a lot so the car can handle the power.
I don't want a real rally car, just something for show and fun.

I think i'll start with the Weber Carb (32/36)
with the reground std cam (to a faster cam)
a milled head (it's cheap and easy to do)
bigger ports (it's easy to do yourself)
and an electronic ignition (it's reliable)

when you do all that DO you need stiffer valve springs? and steel timing gears? a better clutch? bigger radiator?
cause that would make it to expensive.
 
03/05/2005 18:58:02   Alistair   Sounds like you are being sensible about this if on a budget.

My old car had a 1500 with slightly raised CR ~10:1, SAH cam (similar to Saab 7.2mm cam), not sure about valve springs but suspect stiffer as it didn't bounce at 5700, steel balance shaft gear to allow it to rev safely, high pressure oil pump, 2bbl inlet manifold and a variety of carbs, but mostly just a 28/36DCD, and it had a variety of exhausts - some home made/bodged and also a Jetex/Simons system - with the manifold flanges bored out. Also had an oil cooler, Lumenition and S&R spec lighteneed & balanced flywheel. We ditched the S&R clutch for road use, it was kinder to the gearbox! This gave about 85bhp, would rev happily to 6250rpm and was nippy but not fast with standard gearing (0-60 in c. 11.5-12). It would also max out in top gear (108mph) - and frequently did ;-)

Dad used to have a 95 to which we fitted a standard Taunus 17M engine (this is the high compression 1700, not the US/Sonett engine) + home made straight thru exhaust using S&R front pipe, a big twin choke Solex & drank fuel like it was going out of fashion, but would do 110 and pulled like a steam train.

The shorter crank engines (1500 on 90mm pistons, 1531 on 91, 1600 on 93) are more peaky than the long crank engines (1700, 1740, 1815) - the 1700 crank gives them tons more torque.  
03/05/2005 19:50:38   Rens   Hi Alistair, thanks for your reply.

did you know the 28/36DCD is a renault alpine carb? my dad used to race that one. They are quite difficult to get.

But if i get this right. You say a short crank (1500) is for the faster exceleration and a longer crank (1700+) is for the higher speed and more torque?

does someone have any pic's of how to bore the manifold flanges? this is the same as the bigger ports, right?  
04/05/2005 07:55:50   Richard   Ren's if you go to the Vsaab (vintage Saab page) in the USA they have the Saab Sports and Rally manual on line. This gives you all the dimensions you will need.
I would fit stiffer valve springs if you are going for a higher reving cam (V6 items).
The DCD was fitted to Cortina Gt's and even Anglia's in the UK so they are quite easy to find over here.
The best thing to do would be to get your 1500 engine in good condition, check all the parts for wear and make sure everything is up to manufacturers spec. Then do the heads and cam and put a four stud manifold (17M) and carb on it.  
04/05/2005 10:09:12   Jon   Sonnett71 (David), looks like you're doing an extensive restoration!! Are all the other cars cars your too?
Jon  
04/05/2005 10:44:10   david   Unfortunately not! The Sonett II & the Monte Carlo belong to a friend. The white 96 V4 is mine, besides that I still have a 900 CD and a Mazda 323 4x4 Turbo  
05/05/2005 09:36:42   Alistair   28/36DCDs used to be 2 a penny over here and still quite easy to come by. The 32/36 offers more potential though, the good thing about the 28/36 is that it is a progressive carb - most of the time your engine is running on only one choke (the smaller of the 2) with the second choke opening above a certain throttle angle for more power. Makes it more economical than the standard carb!

Manifold flanges just need boring out to match the exhaust/head port diameters, standard ones are quite a step down from head to exhaust. If you put the big bore exhaust on you still have the flange in the way.

1500 crank won't give better accelaration compared with similar spec 1700 - it's just a peakier power delivery - more at the top end than on the long throw crank.  
05/05/2005 12:25:19   Richard   bassically your piston speed for a given amount of revs is lower on the short crank, so a 1500 can rev more.  
05/05/2005 12:33:10   Rens   But why would you use a 1700 crank if a 1500 crank can rev more?  
05/05/2005 15:45:22   paul   The increased capacity from the 1700 crank should give about 10% more torque than the 1500 through the range, the extra revs of the 1500 will only come into play with a good cam and good breathing. Although overall the 1700 crank seems to be perfectly strong, as i thought that was what all the rally boys used. has anyone actually built a 1500 that revs higher than the 1800s, or is the valve train or conrods the limiting factor?
 
06/05/2005 00:24:32   Alistair   The only point I can see in building a highly tuned 1500 is to fit below a 1600cc class limit, otherwise the gains in usable power are so much better with a 1700. If you have the full monty S&R rockers etc with an 8.3mm cam then you might find you can rev a 1500 higher (the works long stroke cars used to get to about 7000 on 7.6 cams, a bit more for circuit racers on 8.3 cams - maybe 8000) so your peak power may be impressive, but at the expense of low- and mid-range grunt. Like a revvy VTEC. It would also likely run like a dog below 2000...

 
06/05/2005 07:52:22   Richard   For road use you are never going to rev a engine up to 8000, keep it at about 6000rpm, unless you want to spend lots of money or you are a nutter (I will start whistling to myself in a corner).  
06/05/2005 15:34:14   Alistair   Good point, that's not what I intended to suggest actually!  
09/05/2005 16:38:36   Rens   This car is just a road going car. So for now (also because of the money). i'll start with the carb, already got the exhaust. That will give me aprox. 75Bhp?
So Weber 32/36, 2bbl manifold, simons exhaust, Petronix coile and electronic ignition and K&N sport filter!

and i'll be a happy camper for now....

Everybody thanks for all of the reply's and i hope i can help you some times!!!  


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