These pictures are very interesting for me. Not the manifold itself, but the diameter to the carbs and to the cylinder heads! The upper diameter fits obviously to the bigger carbs with 44 or 48mm, but the lower diameter looks as the original size of the intake port of a serial Dino cylinder head. I have done the same with my Dino 246 intake manifold to match it to DCNF 44 carbs without modifying my cylinder heads (and hood). Some people called it stupid, but I think it makes sense as the decreasing diameter supports the gas acceleration into the engine. This pictures proves my idea
Back to earlier in the discussion on horsepower gains The stratos modified engines output is all the more impressive as the as built horsepower claimed by Enzo for the Fiat built 2.0 and 2.4 engines was significantly off the mark, where as the Fiat claimed outputs for the 2.0 and 2.4 are much closer to reality Also did not the Stratos have a 2 spark plug heads?
No, they don´t. 2 Spark Heads were only on the 206 Race Engines. The Stratos engines had 4 Valve heads and at the end of the development there were some turbo charged with 2 valves.
Nico, the base of the 44's is not the same as the stock Dino 40's. How did you modify the stock manifold to make them fit? Do you find a performance improvement? Regards, Alberto
I almost missed this discussion. The most interesting fora here are this (vintage) forum and of course the Dino forum. Andres
The manifold is reworked and enlarged/gasflowed at both ends and inside, so are the heads. To fit 48s you need to enlarge it to the limit of its structural integrity as compared to the Stradale Stratos. The usual Stratos parts sources in Italy can provide rough re-cast inlet manifolds that you need to rework completely in order to fit. Only works cars used 4V engines with no more success than 2V ones, these produce slightly more power at the expense of low end torque (undesirable in rallying) and fragility. The 4V engines use a completely different inlet system.
Alberto, they are the same. I compared Weber DCNF 40 with 42 and 44: no difference in the outer flange to the inlet manifold. The DCNF 42 are used on amost all older Maseratis and relatively easy to find. I thought 2 mm more would not make a big difference and looked for the rare 44 DCNF. My inlet manifold was modified to the 44mm ID for the DCNF and was not modified to the 40 mm ID on the cylinder head. For me the same was done with the Stratos inlet maifold, but with 48 and inserts in the cylinder heads.
Nico, look at post #21. That is a Stratos manifold for IDF's. Dino manifold is different, and of course you can fit larger DCNF. Did you gain power? Regards, Alberto
A lot of work and some very rare parts to make the car run better. Our machinist did it the easy way. He just put a Motec fuel injection system on his 246GTS: no new intake manifold required, no bodywork required, no jetting required. Just some Weber replacement throttle bodies and the injection system. He also tailored the ignition curve and fuel mapping to the the engine modifications that he made. Much easier and probably performs better as well.
why change engine lid!!!!!!! this car have original 44 IDF carbs with stratos manifold. no modification made to engine lid original 44 IDF is almost impossible to find today, replicas is no problem Image Unavailable, Please Login
It is not clear to me that fitting larger carbs in itself would increase acceleration over the rev band. A larger bore means slower air flow at low revs, so less torque. You MIGHT gain at high revs if in fact the engine can use that much gas mixture. However, the Stratos intake will increase the intake tract length and thus increase low rev torque, so that might compensate for the larger bore. The main advantage of IDF carbs is that they don't starve the engine in left turns and can be tuned more fully by an expert (IIRC)
this carbs are fitted under std Engine lid no modification made to it, original 44 IDF carbs, 26, 26, 27 this Engine produce 205 hp at 7500 rpm Image Unavailable, Please Login
Peter, Very interesting project! How much clearance once the lid is closed? Any room for an air cleaner assembly? Could you detail out all the parts you used to convert? Freeman