Mancini Racing ARCA W2 engine ** UPDATE**

Finally got the motor on the Dyno yesterday. Very pleased with the results considering what this in this old dinosaur. The limiting factors that Brett stated are what limited the power/tq. The pulls were done on VP 110 but will run E85 when it gets in the car. I also did not have the 2" spacer he suggested, and the headers were borrowed (last minute) and had mufflers in the collectors which robbed some as well.

Brett has the Dyno sheets scanned, any guesses on what it made? Here is a quick rundown. If I missed anything I am sure he will clarify even though he hates to type:

X block- 4.060 bore, 3.454 stroke
No flow data on the heads or intake... see earlier in the post for info on them https://board.moparts.org/ubbthreads/show...part=1&vc=1
1.5 steel rockers
Predator cam
266 in/272 ex @ 050
.430 lobe lift
Lobe sep. 104 in/112 ex
Gross 645 in/653 ex
Cam was degreed in at 104
Gutted lean burn dist w/ a crank trigger
1-5/8-1-3/4 stepped sprint car headers
Timing was happiest at 38°
We tried his Pro Systems Dom as well as my out of the box 1050 which were only a few HP between the
two.Mine liked 88-90 jets, and has power valves in thre front and rear.
The rotating assembly is anything but light, but this is going to be a bracket motor and not out to bend the needle. Oil pressure was through the roof with nothing done to the pump (M72HV).

Nothing fancy in the motor, especially by todays standards. Sorry, no prize for hitting the number, just bragging rights.

488 TQ
588 HP

535 hp at about 7200... did you change anything in
it or is that the way you bought it... if I remember
right you got that pretty cheap so you should be pretty
happy either way

I didnt see the compression of the engine, but the other thread showed a dome on the pistons...So I will assume at least in the 12.5-13:1 range? Hmm...
568hp and I figure 1.38 Lbs/torque per inch so 490ish for torque.

if it does run that kind of compression..
and the cam lift i am seeing..
i am thinking the torque should be pretty good even with only 3.4 stroke.
so my guess..
588hp 442 trq. with the smaller carb.
i bet it sounds nasty.!!
cheapst.

Brian,
I just got off the phone with Brett telling him that i got my 408 that he and i went over this winter fired up today. He told me all aoout the troubles with headers and oiling system line on the motor...

And he told me what power it made, but i won't spoil the fun for everyone else. I'll just say this, that little scamp of yours outta fly with this motor in it! - Andy

Glad you got home OK Brian was a long day to say anything about it LOL. Sorry I did not think about the small bolt pattern exhaust in the heads........... I wish it would have went little smoother but it was all good in the end. I thought it would make little more power than it did.
The header mufflers are for (USAC sprint car rules) and I did not know the headers had them in until we got done on the dyno they have done back to back tests on the 358 chivy stuff and it hurts them about 10 HP and 10 TQ at every point not just peek #s. The header are just to small and the add in collector is necked down to about 2 1/2" (was 3" collector to start) and its 1-5/8 to 1-3/4 primary.
I think the intake is not matched well to this combo and a Indy intake would get us 15~25 HP but just putting 2" HVH deal on this intake should help maybe 10 HP 10 TQ.
Other than that this engine is so smooth pulls right to 8000rpm and on the dyno you can get a "FEEL" for how an engine will take load and how smooth it accelerates and it did that very well.
The oil pressure is WAY to much over 100 psi at 210* oil temp on a back to back pull. I guess we should have got some thin oil to put in it that would have helped HP some.... I guess I should just get done with all the excuses and show the dyno results LOL

Oh BTW dont look at fuel #s the $5.00 distributor and the 15year old wire set was messing up the dynos data acquisition for fuel readings.(To much EMI)

Quote:

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Oh BTW dont look at fuel #s the $5.00 distributor and the 15year old wire set was messing up the dynos data acquisition for fuel readings.(To much EMI)

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I was just about to say 42.2 looks just a little rich