Which cams? (2.5)
#1
Which cams? (2.5)
Hi all
well having much trouble with the scoob and no spare funds, my scoob has been a slow project, funds should be landing tommorow to get a big chunk done. Power fc, walbro, knocklink are all paid for now, pistons rods and bearings will be courtesy of API.
car was orig an Sti v2 ra, but the garage that carried out the conversion(2.5) swapped my heads for ones with hyd lifters and non-sti cams, David (API) recomended sti v3 heads, bit hard to find aren they? what would be a good equivalent? and can anyone recomend anywhere for the valves (back to shims) and maybe some headwork?
Thanks,
Adam
well having much trouble with the scoob and no spare funds, my scoob has been a slow project, funds should be landing tommorow to get a big chunk done. Power fc, walbro, knocklink are all paid for now, pistons rods and bearings will be courtesy of API.
car was orig an Sti v2 ra, but the garage that carried out the conversion(2.5) swapped my heads for ones with hyd lifters and non-sti cams, David (API) recomended sti v3 heads, bit hard to find aren they? what would be a good equivalent? and can anyone recomend anywhere for the valves (back to shims) and maybe some headwork?
Thanks,
Adam
#2
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Originally Posted by Scoob+Bike=Fun
the garage that carried out the conversion(2.5) swapped my heads for ones with hyd lifters and non-sti cams
#3
no i wasnt, the garage WILL be sorting me with o.e spec(as car went to them) or better heads, i'm not happy, suppose i would have never known if i didnt do it myself this time. Not happy about it either.
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Depends what you're talking about. I know of the mythical wild sti3 cams, including the set out of Moray's car, and perhaps one more besides. The DH22 cams on the other hand, as you are probably aware are "very similar" to the cams used on the 98 WRC car. The DH22 have about 268deg total duration with 9.65mm lift. Sti3/4 cams have less than 9mm lift and from memory 256deg duration.
#9
Originally Posted by Scoob+Bike=Fun
no i wasnt, the garage WILL be sorting me with o.e spec(as car went to them) or better heads, i'm not happy, suppose i would have never known if i didnt do it myself this time. Not happy about it either.
The Sti 2 RA heads were very special in the first place, they were the only model fitted with 'Top Hat' under bucket shims. Ok, the cams weren't that special next to the regular Sti 2 (with Hydraulic followers) but the shimming method, buckets and collets were unique
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I wouldn't be dissapointed with sti2 RA heads, although the wrx RA heads should be the same solid follower and top hat shim design.
Sti3/4 heads would IMHO be better still, but mainly due to some extra lift on the cams. The early RA heads are very capable in terms of power.
Hope you get it sorted soon.
Paul
Sti3/4 heads would IMHO be better still, but mainly due to some extra lift on the cams. The early RA heads are very capable in terms of power.
Hope you get it sorted soon.
Paul
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Originally Posted by Mark A
I think Doug meant in terms of lift and duration
I would interested in finding all the cam lift & duration, does anybody know if this information is available?
I would interested in finding all the cam lift & duration, does anybody know if this information is available?
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Picture of top hat shim, and follower.
Originally Posted by Mark A
I also have a set of STi RA 2 heads flowed so I'll be interested to see how they perform
pic of shims and top hat
pic of shims and top hat
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Think there's crossed wires here. I'm aware that you cant go mix and matching. Its just that most people seem to go down the phase 1 route for building engines with above average output. I was just asking to find out if there was any gains to be had? I thought that maybe there would be a difference in metals used, valve/stem sizes, ports/chambers, cam profiles etc. I take it there is minimal difference and the reason phase 1-4 seems more popular is down to availability.
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Originally Posted by doug2507
Think there's crossed wires here. I'm aware that you cant go mix and matching. Its just that most people seem to go down the phase 1 route for building engines with above average output. I was just asking to find out if there was any gains to be had? I thought that maybe there would be a difference in metals used, valve/stem sizes, ports/chambers, cam profiles etc. I take it there is minimal difference and the reason phase 1-4 seems more popular is down to availability.
If you have a v5-6 car and you want to change, you have the same problem, plus nowhere to put the coilpack depending on what you're changing.
It's a common view than the v3-4 heads are physically stronger and less prone to cracking, which is perhaps why the WRC cars use heads based on the v3-4 platform.
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Originally Posted by Zen Performance
It's a common view than the v3-4 heads are physically stronger and less prone to cracking, which is perhaps why the WRC cars use heads based on the v3-4 platform.
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