250 Crossflow - 200kw?

[Anonymous]

i was wondering what was needed to get 200kw at the wheels out of a 250crossflow

i was thinking porting the crap out of an xf efi head, redline manifold with 450 holley, high comp acl pistons, roller rockers, matching cam, 2 1/2" exhaust ( 1 muffler)

i would rather not go efi because i dont like dealing with the computers in cars

how would a t5 box cope with the power.

 

[DYNOED250]

i had a madly ported head, with 2v cleverland v8 valves, xu1 race, grind cam, 240 @ 0.050 322 seat to seat , and 522 lift , with a 650 double pumper, rollers, double springs, pacemaker pipes. bout 12:1 comp due to a head that was milled way to much. and that pulled 167 at the rears.
in my latest motor ive gone less comp, more cam, injection, and long rods, and all acl race series gear and on an engine dyno it pulled 290 hp, about 220 kw, hope fully it will b around 170-180 kw at the rears. ... in si

 

[Anonymous]

would efi be that much quicker than a properly set up carb?

i really dont want to play around with all the computer gear.
if need be though i have a series 2 xf fairmont ghia EFI in the front yard i can rip apart ( complete engine and interior. just bad body)

 

[Anonymous]

Follow dynoed 250s description of mods he did to his engine when he used a carb and I doupt you would get much more power than he did. He says hes spent the money and has done it already. "the proofs in the pudding".
I wouldnt use injection if you dont want to, but I would definitely use a 600 cfm 4bbl of more of carb for this sort of application. Its not going to be as good as injection (econ or power), by how much I dont know.
If I was to guess based on what Ive seen Id say between 5 to 10 percent difference. Anyone?

 

[Fingers]

BOOST

 

[DYNOED250]

a defenite thing we found when trying cames in the last motore is that no matter if its 215 at 0.050 or 240 @ 0.050 the engine still made peak torque at 3500-3700 and peak horse power at 5200-5500, there very hard to shift the toque curve in. even with long rods.
THE BIGGGES THING WITH THESE ENGINES IS EXHAUST THEY LOVE LONG PRIMARYS, BUT KEEP THE DIAMETER DOWM, ON THE PIPES, AND A NICE SIZED COLLECTOR SAY 2 1/2- 2 3/4 ...

200 KW AT THE MOTOR IS FAIRLY EASY TO ACHEAVE CONSIDERING ITS DOUBLE THE STANDARD OUT PUT.

id Do to get a budget 200 kw...

red line 4 barrle...
600-750 dp or vac secondarys.
pacemaker pipes, there a cheap good quality pipe.
stock pistons ID RECOMEND AFTER MARKET THOUGH, deck to 0 deck hight. RUN ARP ROD BOLTS
cc head use.... id use a D cast head or e1/e2 series
if using a c2 which is what ive got get the combustion chamber modifed , remove the bit between the valves.
then id get next size up in valves, and de-shoud them by reliving the chambers.
deck head to get 10:1 comp, if ya game go 10:5.
any moree and u run into dramas.
cam and i 100 persent recomend this one 240 @o.050 522 lift 322 seat to seat.
U NEED DECENT AFTER MARKET RETAINERS THE STOCK ONS CRACK AND FALL TO BITS, GET SOME DOUBLE VALVE SPRINGS AND ADJUSTABLE ROLLER ROCKERS.
GET A CROW DISSY GEAR, RUN A TIGHT ADVANCE CURVE IN THE DISSY, ...

u will need 3.5-3.7s in the rear any higher and its a waste, if usung an auto use a c4 with 3200 or higher stall, if mani then u will have fun.
this combo should easy pull to 5500 and itl rev to 6500 but thers not much point ... but hey ask around other people have difffernt ideas to me

 

[George]

BOOST...For me tooo.

 

[Anonymous]

Dynoed 250
That info you gave on the torque curve staying between 3500-3700 is invaluable info, thanks. I suspected this because of some of the dynoe figures I had seen on square bore big block V8s bear this out.
Ruger XF,
I would be a bit careful about using a 600 cfm carb for this application as one of the hotrod web sites I was on recently said they near stock vacuum levels.

 

[Anonymous]

they "like" near stock vacuum levels.

 

[Anonymous]

BOOST it

 

[Anonymous]

The most significant factor in shifting the maximum torque on a crossflow engine is the length of the inlet manifold runners and the size of the inlet ports.

Crossflow engines suffer from having very small inlet ports, around 34mm. These need to be hogged out to around 40mm minimum without sacfrificing any airflow on the flow bench. Hogging the ports out in the wrong way will make airflow drop in the flow bench. This will significantly reduce the flow losses due to excessively high air speeds.

The best example of an aspirated crossflow I know had the ports milled out into the tappet cover area and water jackets then welded back up. It made 440 hp and 440 ftlb of torque on methanol.

If you are using a carby manifold you are basically stuff with the runner lengths being varied lengths and longish.

With webbers or multi throttle body EFI you can shorten up the runners which will shift torque higher and then you will start making some serious power at the expense of low down torque..

 

[Anonymous]

200KW at the wheels n/a sounds like a shitload of work!!!

id go a medium turbo package, BOOST! Yet again