traveler501 Posted December 14, 2015 Author Share Posted December 14, 2015 (edited) Not sure if anyone else will find this interesting but I've had a long discussion with Isky and sorted out the cam. Based on the valve lift and idling behavior, they figure it has to be their Competition Grind and a valve lash of .018. So, Dingo…many thanks for suggesting that I check this. I would have gone with .012/.022 per the book. It wouldn't have run well at all and might have broken something. Now…back to the exhaust system! PS in double-checking online it seems that .018 gap is for setting when hot. Further discussion with Isky admits that .022 is the catalog cold setting for that cam but .018 cold/hot is recommended for all but heavy racing. So that's that. Edited December 18, 2015 by traveler501 Link to comment Share on other sites More sharing options...
traveler501 Posted December 21, 2015 Author Share Posted December 21, 2015 Just to wrap up this thread, I got the valves adjusted to .018 1/2 per the factory, the carb is completely rejected for altitude and I did an oil change since the motor has completed about 500 miles since the rebuild. So….took it out today and it runs like a top! It's nicely tractable under 3000 and really comes on the cam above that. Sweet sound, lovely car!! Just a quick thanks to everyone for helping me get sorted. I still have to think about the exhaust. I mocked up an extension and took my wife for a drive and she didn't have any problem with fumes,while I still did. I think my COPD and asthma may be complicating things for me, but we'll see. I have a friend in Phoenix who's an old Lotus 7 mechanic and I'm going to get him up here to review the situation. Thanks again! Link to comment Share on other sites More sharing options...
lotusman1951 Posted December 21, 2015 Share Posted December 21, 2015 Not sure if anyone else will find this interesting but I've had a long discussion with Isky and sorted out the cam. Based on the valve lift and idling behavior, they figure it has to be their Competition Grind and a valve lash of .018. So, Dingo…many thanks for suggesting that I check this. I would have gone with .012/.022 per the book. It wouldn't have run well at all and might have broken something. Now…back to the exhaust system! PS in double-checking online it seems that .018 gap is for setting when hot. Further discussion with Isky admits that .022 is the catalog cold setting for that cam but .018 cold/hot is recommended for all but heavy racing. So that's that. Hi if you have COPD-I would not free vent these gases-they go into the air-and unless you are moving -you breath them Kevin Link to comment Share on other sites More sharing options...
traveler501 Posted December 21, 2015 Author Share Posted December 21, 2015 (edited) Thanks, Kevin….I guess dealing with the vent gases is the next step. Do most people vent to a catch can and then into the carb? Edited December 21, 2015 by traveler501 Link to comment Share on other sites More sharing options...
coffee break Posted December 22, 2015 Share Posted December 22, 2015 Thanks, Kevin….I guess dealing with the vent gases is the next step. Do most people vent to a catch can and then into the carb? It depends on which motor you have. My crossflow has a breather pipe only (no PCV) and I have a hose to a catch can. I was curious if anything was being pushed out. Nothing so far I'm glad to report. Link to comment Share on other sites More sharing options...
traveler501 Posted December 22, 2015 Author Share Posted December 22, 2015 hi, coffee break I have the 1600 Cortina GT crossflow engine with the funny dogleg breather and PCV. I could remove the PCV and run a tube directly to a catch can. I like the simplicity of doing it that way. I'm still researching options though such as a) where to vent the catch can (ie center of intake manifold or filter air box) and b) best kind of valve cover available for both venting and also location of oil filler. I'm convinced that venting is needed… now,just looking for the most straightforward approach that actually works (like for example, this crossflow may respond well enough to a manifold vent, certainly that's a easy way to go, and typical for the Cortina GT). I'm interested in success story/strategies for the Vent system…and also sources of useful valve covers, notably that have a filler cap on the scuttle end (right now I just have a vent on the radiator end and no oil filler at all!). Sorry if I sound up in the air….really am at the moment though, doing lots of reading and open to all solutions. cheers, John PS here's what I'm working with... Link to comment Share on other sites More sharing options...
traveler501 Posted December 22, 2015 Author Share Posted December 22, 2015 Ok, so just a quick update. I've read tons of stuff and have a tentative plan for now, which includes the suggestions from everyone above. I'll run a line from the PCV to a catch can, a separate line from the valve cover vent to the same catch can, and then run a catch can vent line to the carburetor plate inside of the K&N air filter. I'll get a cheapie, Ebay catch can and modify it extensively for good oil separation etc…also get a Summit push in Oil Filler cap and drill a hole in the middle of my valve cover to fit it. The line to the carb will be 3/8" ID…I could probably go with a larger ID if I connect to the manifold instead. Does anyone thinks that's a good idea? Should I optimize evacuation and a clean carb but risk leaning the carb and even detonation from oil fumes (manifold port) ….or risk a dirty carb and less vent flow but get better fuel/air metering (carb connection/port)? I'm preferring the carb connection only because I'm trusting the catch can to do a decent job of scavenging and I'm hoping that blowby will be reasonably low on a newly rebuilt engine. Thanks to everyone for all the help so far! I'm pretty psyched after my blast up the local road last Sunday….can't wait for more!! John Link to comment Share on other sites More sharing options...
slomove Posted December 22, 2015 Share Posted December 22, 2015 .... I'm preferring the carb connection only because I'm trusting the catch can to do a decent job of scavenging and I'm hoping that blowby will be reasonably low on a newly rebuilt engine.... Sounds like a plan and this should work, as long as you don't forget to drain the catch can in a timely fashion. Spitting a lot of oil into carbs is not that great. On my old engine, it spew very little oil under normal highway driving (mostly condensed water/oil slurry, drain every couple of months). But it spit out a lot of oil on the track. The windage and aeration at continued high revs, high temps, increased blow-by and cornering/braking hard (sloshing the oil in the sump) made a big difference and required draining after every track session. Link to comment Share on other sites More sharing options...
traveler501 Posted December 25, 2015 Author Share Posted December 25, 2015 Thanks for the response, slomove. I have ordered the catch can, I do have one quick followup question though. Do you think I'll generate enough vacuum by hooking up inside that K&N filter? Does anyone else have a simple downdraft Weber and K&N running to a catch can? (oh, and Merry Christmas everyone!) Link to comment Share on other sites More sharing options...
slomove Posted December 25, 2015 Share Posted December 25, 2015 ....Do you think I'll generate enough vacuum by hooking up inside that K&N filter?... I don't believe this is an issue. I have the catch can vented to the engine compartment, not the intake. No problem with my old Zetec and so far not with my new SVT Zetec as well. I don't smell oil and the little oil mist that does come out takes care of the corrosion proofing But if you vent into the intake, the minor vacuum (intake flow greater than blowby flow) will probably make sure that the fumes go back into the engine and do not escape through the air filter. Link to comment Share on other sites More sharing options...
traveler501 Posted December 25, 2015 Author Share Posted December 25, 2015 Thanks, slo…that makes sense. In hindsight, my crankcase is venting directly into the engine compartment right now (without a catch can)…and it idles fine despite spitting fumes. I got my head twisted around for a minute there :jester: Link to comment Share on other sites More sharing options...
traveler501 Posted January 1, 2016 Author Share Posted January 1, 2016 (edited) So I finally got a few minutes to myself (working around holiday family stuff) and hooked up the PCV and valve cover vents and that solved everything! Turns out I wasn't actually smelling the exhaust at all, it was just fumes from venting the engine to atmosphere under the hood (as many of you suggested). Took it out for a test drive and no fumes…took the wife with me, and as much as I like the 7 judging by her wide grin I suspect she likes it even more (we've been together 15 years and she continues to surprise me!). Thanks to everyone for all the helpful advice. Happy New Year!! Edited January 2, 2016 by traveler501 Link to comment Share on other sites More sharing options...
Off Road SHO Posted January 2, 2016 Share Posted January 2, 2016 Good to hear. We're going for a blat on Sunday if it's not too cold. You know, down in the 60's. :-) Tom Link to comment Share on other sites More sharing options...
traveler501 Posted January 3, 2016 Author Share Posted January 3, 2016 hi, Tom Thanks for the offer (which I saw a bit late, I'm afraid!). Hope you had a great blat. As for me, I'm still getting acquainted with my car. I took it for the first protracted run yesterday and am noticing that my reasonable top speed (considering gearing) is about 60 mph. I think it's been set up for autoX maybe…so not sure how that will fit in with you guys (or commuting to Phoenix either). Do you ever get up this way? Link to comment Share on other sites More sharing options...
Off Road SHO Posted January 3, 2016 Share Posted January 3, 2016 We haven't ventured too far from the Valley yet, but plan on a blat on Highway 89 and 89A from Wickenburg to Sedona in the Spring. We'll give you a heads-up when we finalize the plan. Tom Link to comment Share on other sites More sharing options...
Kitcat Posted January 3, 2016 Share Posted January 3, 2016 501: How many RPM's at 60 mph? I vaguely remember that my 5sp X-flow turned about 3800 at a cruising speed of 70 in the overdrive 5th gear. And that was plenty buzzy, tho somewhat muted by deafening wind noise:). Link to comment Share on other sites More sharing options...
traveler501 Posted January 4, 2016 Author Share Posted January 4, 2016 (edited) hi, Kitkat As you know it's hard to even see the tach around the steering wheel (!)…my best sense of it was that I was hitting 3500 or so at 60 mph. I think I have a stock Cortina 4 sp with 4.10 diff gearing. I'm going to try and get her out again tomorrow (between the expected raindrops)…I'll try to get a better reading. (I'm being a bit conservative on revving it right now since the motor only has about 750 miles since being rebuilt). Tom: that sounds good, I'd really enjoy meeting up with you guys…seeing your cars and comparing notes. Later in the Spring gives me more time to get to know my machine. You know how that is…looking for any surprises….leaks etc. Edit: the weather turned surprisingly ugly…constant rain then snow for the next week. I'll report back as soon as I can though. Itching to get back in the car ! Edited January 6, 2016 by traveler501 Link to comment Share on other sites More sharing options...
traveler501 Posted January 12, 2016 Author Share Posted January 12, 2016 The weather has been too cold and wet for a drive, so I've moved full speed ahead on my exhaust system. Long story short, I hope to have the Magnaflow that Skip Cannon recommended in place early next week. In removing the old exhaust I found several leak points btw…another contributor to the fumes I was breathing. I assume a new (and welded this time!) exhaust should wrap things up nicely. I just have one idle thought before putting this to bed for good. I'm wondering about the uncovered area in the back where the gas tank and diff are. I've noticed that some people have shelves, and some have tonneaus over this area. Does anyone have any experience whether this is another source of fume circulation? I can imagine it pulling fumes up…also imagine it allowing air flow from the rear of the car to move forward, down and through. I hate to re-invent the wheel…has anyone already explored this one way or the other (taped ribbons to the gas tank while driving etc?). Do racers feel the need to cover it? If it effects top speed it must be creating drag one way or the other. If nothing else I'll do the tape trick myself when I get my car back, and report on it. Thanks in advance for any thoughts! Link to comment Share on other sites More sharing options...
traveler501 Posted February 12, 2016 Author Share Posted February 12, 2016 So, it's a month later…weather is nicer and my Tig welder guy finally found a free day to come over. Long story short I installed a Magnaflow muffler per Skip Cannon's recommendation and bumped the exhaust tubing size up to 2". I'm thrilled with the results. Great sound, not as loud as before, motor runs better with 2" (versus 1.5 before) but the big news is that the whole fume issue totally "evaporated!" Thanks to everyone involved…had my first real blat today and loved it…. cheers, John Link to comment Share on other sites More sharing options...
Off Road SHO Posted February 12, 2016 Share Posted February 12, 2016 Looks good. I hope the rear mounts are flexible because that much tubing is going to expand when hot and will move the muffler back about 1/4". Are you ready for a blat down the switchbacks to Sedona? Link to comment Share on other sites More sharing options...
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