Hallys Trop Green GTi
- Thread starter Hally
- Start date
I've just looked at the spray bars I have here and they are basically a banjo type arrangement, not unlike brake lines. There is an oil feed hole on the end cam bearing (furthest from the chain). I don't know if that is the same on an RR head? The oil looks like it comes up the side of the bolt shank from the top of the cam holder so either the hole is wider to allow oil out of the top of the holder or there may be a hole in the bolt, but I think that's unlikely as I can't find one with a hole in. If you need any pics of a nonRR head I've go one stripped out here. Let me know.
Ideally, its pics of some bare RR heads i could do with.
Chris's head doesnt have that oil hole that you refer to, i want to know if all RR heads are like this.
Ive already found one pic that shows a RR head with an oil gallery for spray bars:
http://www.modified.com/tech/0311scc_sr20_engine_buildup/index.html
On the highport, the oil goes through the oil hole, up through the oil gallery in the cap...the oil gallery in the cap merges diagnally into the bolt hole, the bolt hole is slightly larger than the diameter of the bolt allowing the oil to run upto the spray bar.
EDIT - Chris or anyone else with a RR DE, can you do me a favour? Remove the valve cover and crank the engine over with the distributor disconnected...just to see how the RR cams are oiled.
Chris's head doesnt have that oil hole that you refer to, i want to know if all RR heads are like this.
Ive already found one pic that shows a RR head with an oil gallery for spray bars:
http://www.modified.com/tech/0311scc_sr20_engine_buildup/index.html
On the highport, the oil goes through the oil hole, up through the oil gallery in the cap...the oil gallery in the cap merges diagnally into the bolt hole, the bolt hole is slightly larger than the diameter of the bolt allowing the oil to run upto the spray bar.
EDIT - Chris or anyone else with a RR DE, can you do me a favour? Remove the valve cover and crank the engine over with the distributor disconnected...just to see how the RR cams are oiled.
Okay, been comparing and measuring stuff.
Some facts:
- The Spray bars are fed seperately through the seperate oil hole on the non RR head which merges into the cam cap about half way up.
- The cam journal oil holes are fed from the cam cap bolt holes. *This is important, please read on.
- The end cam cap bolt holes in question are stepped diameters on both the RR and non RR.
- On the face of the cap that meets the head, the diameter of the hole is 6.40mm, on the face the spray bar mounts on, the diameter is 7.6mm. (Note, the spray bar gallery merges on the 7.6mm section).
-The bolt diameter is 6.37mm on all bolts
- The bolt hole diameter on the head is 6.47mm.
Onto the the photo's, so you can see for yourself.
So gathering all this info together, we know there is an oil feed from the cam bolt hole to the cam journal. This leaves a potential option to fit spray bars and use this feed...However on a RR, this only leaves a 0.03mm gap for oil to potentially flow through from up the cam bolt hole to the spray bars, opposed to over 1mm gap on a non RR head having its own dedicated feed.
Now to me, the spray bars will be impaired severely on a RR head without modding the lower section of the cam cap to a bigger diameter. Surely the 0.03mm gap is gonna flow very very little oil. Its worth noting with the bolt fitted, i cant see any gap or daylight through at all, with the indicated 0.03mm gap. Kurt apparently ran his like this and says it worked.
To me, the best option is to modify the cam caps so they are opened up to 7.5mm all the way through. Then the only slight restriction is the 6.47mm bolt hole on the head, with a 6.37mm bolt. This would leave a 0.1mm gap for the oil to flow through, still small...but much better than a 0.03mm gap.
Soooo, I'll get a pair of caps modified Chris, and send them in the post along with the spray bars and longer bolts.
Dont suppose you had the valve cover off today Chris to check it over??
Some facts:
- The Spray bars are fed seperately through the seperate oil hole on the non RR head which merges into the cam cap about half way up.
- The cam journal oil holes are fed from the cam cap bolt holes. *This is important, please read on.
- The end cam cap bolt holes in question are stepped diameters on both the RR and non RR.
- On the face of the cap that meets the head, the diameter of the hole is 6.40mm, on the face the spray bar mounts on, the diameter is 7.6mm. (Note, the spray bar gallery merges on the 7.6mm section).
-The bolt diameter is 6.37mm on all bolts
- The bolt hole diameter on the head is 6.47mm.
Onto the the photo's, so you can see for yourself.
So gathering all this info together, we know there is an oil feed from the cam bolt hole to the cam journal. This leaves a potential option to fit spray bars and use this feed...However on a RR, this only leaves a 0.03mm gap for oil to potentially flow through from up the cam bolt hole to the spray bars, opposed to over 1mm gap on a non RR head having its own dedicated feed.
Now to me, the spray bars will be impaired severely on a RR head without modding the lower section of the cam cap to a bigger diameter. Surely the 0.03mm gap is gonna flow very very little oil. Its worth noting with the bolt fitted, i cant see any gap or daylight through at all, with the indicated 0.03mm gap. Kurt apparently ran his like this and says it worked.
To me, the best option is to modify the cam caps so they are opened up to 7.5mm all the way through. Then the only slight restriction is the 6.47mm bolt hole on the head, with a 6.37mm bolt. This would leave a 0.1mm gap for the oil to flow through, still small...but much better than a 0.03mm gap.
Soooo, I'll get a pair of caps modified Chris, and send them in the post along with the spray bars and longer bolts.
Dont suppose you had the valve cover off today Chris to check it over??
I love this.
Dale, you the man.
TBH I doubt I will get chance to take the VC off until the weekend, and i'd rather the only time I do take it off is to fit these modded end caps and bars. I will be sure to take some pics to see if I can work out what is going on.
If I do as you suggested and crank it with the dizzy disconnected, would oil not go everywhere?
Cheers for all the research and measuring!
TBH I doubt I will get chance to take the VC off until the weekend, and i'd rather the only time I do take it off is to fit these modded end caps and bars. I will be sure to take some pics to see if I can work out what is going on.
If I do as you suggested and crank it with the dizzy disconnected, would oil not go everywhere?
Cheers for all the research and measuring!
Reet, fitted the spraybars, modified caps and bolts today. I couldn't get the spraybars working with the VC off cranking it on the key but I hope they are. I tried to look inside the oil filler while it was running but you cant see anything at the speed the lobe flys round. Just hoping they have enough pressure to work!
On inspection, the cams are in OK condition. A few marks but no scoring, couldn't feel anything with my nail. They were coated in oil too so they must have been getting some lubrication.
Before:
After:
And a video I tired to take through the filler cap. please just turn the sound off as it sounds awful, but that's not the engine so don't worry, just the way the camera has picked up the noise.
On inspection, the cams are in OK condition. A few marks but no scoring, couldn't feel anything with my nail. They were coated in oil too so they must have been getting some lubrication.
Before:
After:
And a video I tired to take through the filler cap. please just turn the sound off as it sounds awful, but that's not the engine so don't worry, just the way the camera has picked up the noise.
Nice work mate, I really hope it is spraying the cams as it would be a big shame seeing a sweet DE engine fail.
I LOVE those lobes
The spray bars should still spray some oil out even at cranking over rpm, even if it is just a dribble, maybe wipe the spray holes clean so it is easier to see new oil coming out of the holes? Any chance that the bars are clogged up?
I LOVE those lobes
The spray bars should still spray some oil out even at cranking over rpm, even if it is just a dribble, maybe wipe the spray holes clean so it is easier to see new oil coming out of the holes? Any chance that the bars are clogged up?
If it were me I might be tempted to drill the needed holes down into the oil gallery and use the matching cam caps?
- I'M ON MY MOOOBBIILLEEEE!!!!!!!! -
- I'M ON MY MOOOBBIILLEEEE!!!!!!!! -
I've got a whole non rr lowport head in my shed at the moment, has everything connected on it, so if you need any pics mate just let me know 
Cam lobes look fine still, no different to when they were installed.
Glad you got the spray bars fitted okay, I dont think theres enough oil pressure when cranking on the key. Even with mine, It takes a good 20-30 seconds on my highport to get anything coming out, this is with its own dedicated oil feed.
On the lowport head, we've pinched from the feed for the cam journal, so I think the pressure is too low and the oil is taking the easiest route out of the cam journal hole.
Glad you got the spray bars fitted okay, I dont think theres enough oil pressure when cranking on the key. Even with mine, It takes a good 20-30 seconds on my highport to get anything coming out, this is with its own dedicated oil feed.
On the lowport head, we've pinched from the feed for the cam journal, so I think the pressure is too low and the oil is taking the easiest route out of the cam journal hole.
both cars are looking good lads, nice pics too :shades:
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