cams
- Thread starter ggfrank21
- Start date
I can't find the duration but here are some lift/flow numbers I was found a while back...
Lift / Intake / Exhaust
0.1 / 92 / 67
0.2 / 153 / 123
0.3 / 214 / 143
0.4 / 230 / 154
0.5 / 259 / 161
The manual specs camshaft lobe lift at 5.55mm with a 1.8:1 rocker arm ratio for a theoretical valve lift of 10mm.
Lift / Intake / Exhaust
0.1 / 92 / 67
0.2 / 153 / 123
0.3 / 214 / 143
0.4 / 230 / 154
0.5 / 259 / 161
The manual specs camshaft lobe lift at 5.55mm with a 1.8:1 rocker arm ratio for a theoretical valve lift of 10mm.
ggfrank21
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You wouldn’t happen to know the piston compression ratio would you. I could use any other spec about the 4.6 4v you might fined helpful
I bought another mark viii 4.6 and I’m going to do a tare down and rebuild and upgrade, all I’m keeping off the build motor is the block and heads trying to find specs to help me decide what cams to go to and I’m up in the air about boring to larger piston and higher compression and what intake flows better the stock 94 or a 96 cobra. I’m not going to C heads but want to hone and improve the stock heads. Cobra cranks and rods and I also need info on what headers will fit. IIM NOT BUILDING A RACE MOTORE but improving the old getting out what I can but still stay in the state emissions. I would love any help I can get
I bought another mark viii 4.6 and I’m going to do a tare down and rebuild and upgrade, all I’m keeping off the build motor is the block and heads trying to find specs to help me decide what cams to go to and I’m up in the air about boring to larger piston and higher compression and what intake flows better the stock 94 or a 96 cobra. I’m not going to C heads but want to hone and improve the stock heads. Cobra cranks and rods and I also need info on what headers will fit. IIM NOT BUILDING A RACE MOTORE but improving the old getting out what I can but still stay in the state emissions. I would love any help I can get
The Mark VIII valve head diameters from the manual...
Intake - 37mm(35mm gauge diameter)
Exhaust - 30mm(28mm gauge diameter)
The '96 Cobra DOHC valve head diameters from the manual...
Intake - 44.5mm(42.5mm gauge diameter)
Exhaust - 34mm(32mm gauge diameter)
A lot of info can be found on the DVD manuals you can pickup on eBay. Mine is a FLM '92-'96 manual.
DLF
Registered
That's not correct. All "B" heads have 37mm intakes and 30mm exhausts. There's a mistake in the '96 Cobra manual, it lists the valve sizes for the 2V engine. This was corrected in the '97 and '98 specs.
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DLF
Registered
1.8:1 is correct.
'98 Cobra:
CAMSHAFT Lobe Lift
Intake (Primary) 5.57472 mm (0.21839 in)
Intake (Secondary) 5.55672 mm (0.21877 in)
Exhaust 5.55152 mm (0.21856 in)
Theoretical Valve Lift @ Zero Lash
Intake (Primary) 10.0 mm (0.3937 in)
Intake (Secondary) 10.0 mm (0.3937 in)
Exhaust 10.0 mm (0.3937 in)
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ggfrank21
Registered
so far im thinking of changing the pistons to forged (havent made up my mined of staying with the 9.5:1 compresion and get a SC or stay normaly asprated and get 10.1:1 compresion Pistons) Get new rods again Forged, BUT havent made up my mined of geting a new crank. **Im not planing on exceding 400 Hp at all and have never personly heard of a crank braking.** the heads from what i can tell the valvs are the same a the cobra and there isnt any room for larger valvs (but not sure if this is corect) have heads cleaned and polished and better springs instaled. and im looking at two diferent sets of cams in summit's web sight the comp cams 106300 and the comp cams 106060. PINNY FOR YOR THOUGHTS any feedback welcom. this will be a every day driver needs to pass texas smog test just wasnt more and relyable power. this is for my 94 mark but the motor i got to rebuild is out of a 95 Cont.
My thoughts...
If you go SC, go with a forged crank because you will likely find yourself going for more boost.
If you plan on N/A, go with the higher compression and you can likely stay with a stock crank. The rods and pistons are good candidates to be upgraded in either case.
I think the 106060 cams would be a better street cam.
If you go SC, go with a forged crank because you will likely find yourself going for more boost.
If you plan on N/A, go with the higher compression and you can likely stay with a stock crank. The rods and pistons are good candidates to be upgraded in either case.
I think the 106060 cams would be a better street cam.
ggfrank21
Registered
if if i go with compresion over SC and the 106060 cams and i will be doing the exhost during the motor swop with the headers from super coup performince and iv already upgraded the fule pump 255lph what kinda of crank HP over the stock 280 you think i would get. and ill get the LMS chip. id like to get aroung 350 bhp. PS how do i get the water tubing that conects the heads to the radeater
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PalmettoMarkVIII
Registered
You have another, more pressing problem. The Conti came with the front wheel drive version of the 4 cam 32v 4.6L. You cannot use this block in a rear wheel drive Mark.