What can I expect from this 1300?

[Chris bugster]

I am trying to convince a friend that he should have me build him a highish rpm/hp 1300cc engine as a bit of an experiment. The budget is tight and he only has $650 to spend. The engine is generally sound and the only additions will be a Scat C45 (about Engle 120) with new standard lifters, ported stock dp heads with hd single springs, 9:1 compression, 1 3/8 header and second-hand 40IDFs. I would like to see 80-90HP out of it as that's what most of the local 1776s round here make. It would be funny to get this 1300 in the same hp range.
Any recommendations? Any experience of an engine like this? I don't as all the engines I have built started at 1776.

[Zach Gomulka]

Unless you have a pair of the [rare in the States] European dual port 1300 heads you're going to have some work ahead of you getting the 1300cc (77mm) cylinders to work in the 1600cc (85.5) heads. In the Pure Racing section there is a big thread on mouse motors. Check it out

[Chris bugster]

They are the dp 1300 heads as I am in europe . I expect some work on these heads anyway as the chamber will have to be welded some to get the required compression which needs to be at least 9:1

[Chris bugster]

Zach, I live in the country your ancestors, judging by your surname, came from at some time in history. I know the thread you refer to very well and it would be nice to do all that is required to achieve the maximum possible but, unfortunately, funds are limited. The port work will be free, but those heads cost him $130 second hand, which ate into the budget considerably. The carbs, manifolds, filters and linkage and rebuild kit also added another $350 so there isn't much left.

[dannyboy]

alan at gac makes about 114-125 bhp from a single port 1300 v spec engine running a single 40 dell or webber idf

[Chris bugster]

That's impressive.

 

[dannyboy]

stock crank as well revs to 7.8k
they only do about 500 miles before needing a rebuild 

[Torben Alstrup]

Too much cam to make a small engine like that driveable. Engle W110 max. (That is also one of the few times you´ll see me advocate a W110  ) But it works quite well there. Keep the ports smal, only clean up the sharp edges ! shorten the valve guide 5-6 mm. good valve job.. 9-1 CR is good.
A set of dual 36 Dellorto´s (or IDF´s) will do wonders. Buy a vacum can for dual carbs, and modify the stock distributor. (You can achieve better thottle response in the lower midrange)
Lighten tyhe flywheel 1 kg.
A regular 1 3/8" T bird header will do. A Phoenix 1 3/8 merge would be great.
Performance should be in the 80 -85ish range. A bit low to his expectations, but it better to have 80 hp that works than 90 that dont.

I have built a couple of 94 - 100 hp 1300´s for historical Rally. But I would´nt recommend those engines for street cars.

T

[RMS Boxer Service]

With only $650 to spend on this project, leave it alone and enjoy it as it is.
Don't get me wrong, I'm not trying to cool down your entusiasme for
aircooled vw's but it's simply not possible to build on such a tight budget.

/Rolf

[Chris bugster]

Thanks for the advice Torben, exactly what I was looking for. 80hp will be fine and I suppose I was stretching a bit wanting more. I have a bunch of old Webers, most of them 40s, but there should be a pair of 36s in there somewhere. At what kind of rpm did these 80-85 hp 1300s make their sweet spot with a 110?I have used this cam in 1776s and they make peak hp at between 5000 and 5500rpm depending on headwork and compression. I suppose the range will be higher in a 1300. Does a stock 180mm clutch hold this kind of power?

[Torben Alstrup]

Initially I agree with Rolf. But when the project is rolling, he´ll find the last money 

The two I have built, - and that is at least 10 years ago, pulled max at about 55- 5600 rpm. I limited them at 5800 to help rings to stay alive.
Just came to think of it. I built a 1300 DP around a CB 2239 cam 4-5 years ago. Except from valvetrain noise in the level of a W110, I really liked that engine. It pulls slightly less hp, but is very driveable and has good overall torque. I remember we installed 28 mm venturies in it to both limit rpm power and increase lower midrange torque. It pulled something like 74 hp and 117 Nm torque. it pulled about 4 hp more with larger venturies, and reved more, but the best overall power was with the smaller venturies.

T

[Zach Gomulka]

Zach, I live in the country your ancestors, judging by your surname, came from at some time in history. I know the thread you refer to very well and it would be nice to do all that is required to achieve the maximum possible but, unfortunately, funds are limited. The port work will be free, but those heads cost him $130 second hand, which ate into the budget considerably. The carbs, manifolds, filters and linkage and rebuild kit also added another $350 so there isn't much left.

Poland?

Your english is very good, I would have never guessed you weren't from an english speaking country.

What size valves are in those heads?

[jaqo]

Zach, he lives here but he's English.
This engine will be a nice thing - power gain to cost ratio will be good. Carbs <100$, heads in excellent condition 140$, manifolds,linkage, filters ~200$. We can do everything except machining (but that's cheap here) so we'll probably throw a cam there, but after reading what Torben wrote it will probably be a c35.

[jaqo]

But when the project is rolling, he'll find the last money  
T

So true - he already spent ~1000$;)
headwork almost done:


heads were welded so we could get a nice compression ratio, guide bosses were removed and ports smoothed.
Chambers will be polished and ports matched with manifolds

Spec will be:
checked case, crank, rods
vw pistons with a dome
double port cylinder heads welded (9.2:1 comp ratio)
new bearings, rings, oil pump
scat c35 cam
scat lube a lobe lifters
scat bolt-up rocker shafts
swivel feet adjusters
new valve guides, ground valves and seats
scat single HD valve springs
36 idf carbs
cb hex bar linkage

[Torben Alstrup]

Like I menthioned earlier, the C35 will be a bad choice for the combo. Not enough port vacum at lower rpm. a W110 would be better, or ½ step down to a CB 2239. (with 9-1 CR)

Check that the piston dome clears the welded area in the heads.
T

[jaqo]

Check that the piston dome clears the welded area in the heads.

Did that already - there was just  a little bit of interference but I sorted it out.

[Chris bugster]

The engine is up and running and Torben was right about cam choice. The cam (C35) feels big in this combo. It pulls from about 4000rpm to over 6000rpm and feels like a modern 16v engine. The gearing in the car is long- he hit 90mph in 3rd gear and the needle on the speedo stopped on the 0 km/h in 4th gear not long long afterwards. It would be nice to get it on the rollers to see what it actually makes.
It ended up costing just over $1000.

[andy198712]

I'm really tempted to build a 1300 turbo, I would do 1200 but 1300 let me use better crank and rods....