Cherik

Breezy 7, where are you located? There's a few of us in IL / WI. BTW nice site! Cherik

having had a few non-catastrophic-catastrophic suspension failures (deDion tube, 1/2" bolts, balljoint) on the car, I have since replaced the Grade 3 bolts with grade 8 plated. Anything that mates up with a bushing (suspension arms etc.) should be verified to really mate up with the bushing, i.e. no dirt or rubber pieces in between. A rear shock bolt sheared off, dropping the car down "pretty far". The lower front A-arm balljoint was perhaps expected, as these are of the "exposed" type. Given the high miles on the car and Wisconsin's weather pattern, I should have replaced these earlier: The left front slowly tightened and caused the nyloc to back-off over time. I had heard slight crunching when parking the car a few times and one day just before driving out, the left front arm fell down inside the rim... oops. No damage, but the joint had to be replaced. As a standard measure, I check all main suspension bolts before any major event (big drive or track day). The spares I carry: clutch cable, bulbs, fuses, lots of ty-raps, some bolts. Cherik

Al, glad you enjoyed the site. The "water pressure" depression is a measure of the vacuum. 394" H2O is 100% vacuum. More vacuum (50") is more flow. However, it's not linear.... can't just multiply the numbers with 50/28 and come up with the matching flow. All I meant to say is, a fair comparison is a bit obscured by using different vacuum levels. But it looks they are actually very similar. Ignore the lifts >.4". You'll find most cams doing around 9.75mm lift. However, I recall from when we recently put a new head on Graeme's engine, he compared the two heads you are looking at and we found that the cossy head uses stock size valves, whereas the Focus sport head uses 2mm larger valves and will thus flow more because of that ( at the same pressures) He decided for the Focus Sport head. (as you pointed out - similar price). The Focus head was not skimmed however, so that had to be done separately at a local engine shop (approx $70), but we had to do the "cleanup" afterwards. Cherik

one other thing to consider is if you plan to race in a particular class - i.e. modifications: valve sizes, porting etc are limited in certain classes. I'd check to see which classes these heads are allowed in. As far as a build-up, used ZX3's are not expensive, a short block costs much less ($300...$750) than all the parts you're going to add. It's a lot more fun to take your time building the new engine that way and not have your car out of commission. Cherik

Al, I can't say enough how much we enjoyed being part of the magical event! Ok, here goes $.02 - it's not all personal opinion, there's some trial and error experience in here as well :-) The flow numbers look very good. The 28" / 50" would translate to.... 10mtr H20 Column = 1 Bar, or 14.5 psi, so then 40" is about 1 mtr, or .1 Bar or 1.45psi. Point of that is to acknowledge the inherent turbulence effects which make the flow numbers non-linear with the degree of vacuum. The pics on the Cosworth website look very good. The CNC method should yield a very predictable result and with their enormous knowledge base likely a very good one. Having said that, it's interesting to see that for most commercially available 300...400cc cylinders the .4" lift is viewed as a reasonable limit for street ( The graphs confirm that. But.. think about where you want to go make the power with that head. A cam with a fast rising opening profile is what you'd be looking for. The best way to extract max performance is to consider the whole path: TB's, manifold, tract, valve profile. Then dynamically look at the opening transition (as fast as the cam drive allows) and the edge turbulence effects - these are usually quoted at or near .040" lift. This is the initiation of the stream into the chamber. The interesting parameter to play with is the intake cam adjustment - small steps can cause big changes in torque profile. From my past tinkering I know that small edges and steps can really spoil the flow in any intake system. Somewhat less so in the exhaust, due to the higher pressures. Intake trumpet profile is critical as well. Make sure you have at least 90dg curled flares, but better is to get the full 180dg curled intakes. Look at their flow numbers (!). Anyway, many chapters have been written on this, but in the end you have to go play with it to get the maximum. I'd suggest to ask RMSCI if that head was ported.... I thought Jon N. quoted 220HP with his combined TB/Manifold with a slightly ported head, 270dg/9.7mm cams, and 10.5 CR, but I could be wrong. Cherik

Al, do you have one of Jon Nelson's (RMSCI) ported heads on there now? That TB/manifold he made is quite good. The standard TB's (like Jenvey / Lumenition) have a kink that limits power >7000rpm. Contouring the TB/head transition and gasket with a dremel tool (sanding drum / polish weheel) can solve some of that. I doubt if the Cossy head will give more, although combined with Jon Nelson's TB/Manifold it might. Of course, this is probably for flow >7000rpm. Not sure it'd help for Auto X. You'd want to play with gear ratio's for that :-) As far as cooling issues - I agree with Bruce regarding the Raceline water rail. It does clean up the mess. I use a plastic vented over flow bottle to check the water level. The filler cap has the dual vent valve in it to prevent undue evaporation. Cherik

Bruce is correct. The latest is 69,500 miles as of this evening. Mostly daily driving miles. Two to four track events a year. No salt miles :-) The speedo indicates 4 k miles less, as I had to replace two of them in the early days. Cherik

all true. I assumed he was talking about 1/4 throttle and that it ran ok past that (main jets / mix jets). The standard jets that C'ham (Grand Prix Enterprise/London) puts in the Webers are quite good, but that can't do anything below 1/4 throttle, which is at least what I experienced. The transition circuit (progression holes) are fine on the DCOE 40's, but not the 45's - John Hartley had to drill a few extra's to get those to run properly. Cherik

ha! My very supportive wife thinks I'm married to the car. I spent 28k miles with that Crossflow and the procedure was repeated until it was so well choreo-graphed, I could do it in my sleep. The Zetec is so much easier, just put gas in and drive, and only tinker with the map when the season changes. Cherik

Two rides. I gave Preston Lerner (Automobile mag journalist) a ride during the parade and later Bruce W. after the photoshoot. As Bruce mentioned, it started to rain, which could have been even more fun, except there were a couple motor bikes in front... Cherik

Many thanks to the 7-7-7 team. Super job. The solid preparation was evident in everything. Brilliant event. How can anyone top this? Here are some pics . We (Greame G., Jeff P., John M. and myself) were putting Fred K's car back on the trailer when Mr. Wilson with his well running classic S1 arrived. Asked if he could help and if there were more 7's around. He mentioned he'd rarely seen another se7en... We send him to the Tapoco lodge, figuring someone would direct him to the meet. Glad to see him in front at the photoshoot. Fred's car had broken the rear A-arm joint, fortunately he "landed" it without indicent. The 1st pic is at the overnight stop in Kentucky... ok, so there were a few cops around. Next is Mr. Wilson stopping by to help. Other pics from the magical Saturday 6AM dragon run Last pic from the 4pm Sat photoshoot and also Graeme's and myself with our cars. http://www.usa7s.com/aspnetforum/upload/997661593_IL-WI-team-Jul6-07.jpg http://www.usa7s.com/aspnetforum/upload/1193101921_Mr-Wilson-1.jpg http://www.usa7s.com/aspnetforum/upload/1369385956_6AM-Dragon-run-2.jpg http://www.usa7s.com/aspnetforum/upload/147322935_6AM-Dragon-run-9.jpg http://www.usa7s.com/aspnetforum/upload/276759397_6AM-Dragon-run-Lookout-5.jpg http://www.usa7s.com/aspnetforum/upload/981192898_6AM-Dragon-run-Lookout-7.jpg http://www.usa7s.com/aspnetforum/upload/485668153_USA7-ps-2.jpg http://www.usa7s.com/aspnetforum/upload/1392426026_Tapoco-12-GG-n-CB.jpg Cherik

Got my EE & ME degree in the Netherlands where Lia and I both grew up. My 7 intro was by means of the Prisoner series. I wanted one since I was 15. I used to build "experimental" motorcycles back then from scrap. One even had two engines (front and and rear) but was confiscated by the Dutch police and subsequently crushed. Rode a bicycle for the next two years. Got heavily into two stroke tuning. A major pass time in the Netherlands at that time. I got back into that in the late 80's. I keep a very good Suzuki T500 and a nice Yamaha RD250. Came to the US in '80 and went to work as an Electrical development engineeer for a large engine control company (Cooper) - fuel / ignition control for the big 50,000hp machines. They were 300..600rpm hot-rods at the time, two stroke 8..16 cylinder, 20..30" diameter pistons :-) We moved to Wisconsin to work for GE Medical. MRI was just starting. Spent 22 years there. Left in '05 to with three others form a wireless bio-implant company. Got the "7" finally in '99 - see my website. After 70k miles it's still as exciting to drive and work on as when I first got it. I also have come to appreciate the people associated with this hobby. A very special crowd, typically humble enthousiasts and with great energy. Other interests: High end audio, RC helicopters (crashed many), hiking Cherik

I used to run this exact configuration and found the setup to require a few sequential steps to address this. Depending on the altitude you will need to correct a bit, but 1/4 throttle A/F is all set with the "idle" mix screws. They are really for all 1/4 throttle and below settings. The progression circuit is for 1/4 to 1/2 throttle. The main jets matter from 1/4 and up. Smaller venturies (30mm) make for very strong low end ( 32mm is probably about right for that cam and exhaust, 34 and up is large. Weber recommends 80% diameter for good low and mid range fuel mixing. 1. Assuming idle timing is 14dg and climbs to around 20dg at 2000rpm and lands somewhere around 28-30 at 3500. 2. Set the idle with the throttle screw to around 1500rpm 3. check the flow in the 1/2 vs 3/4 carbs - adjust until absolutely equal - use the-hose-and-ear method (1/2" hose in each barrel and listen for equal noise) or best is a flow meter. Avoid using a vacuum meter on these large carbs, it's not accurate. Flow meter I used is the German STE Synchrometer model SK. Set flow to about 5kg/hr. Take several turns to do the balancing. 4. stop the engine and while keeping track of the turns close all the mix screws gently - note these are tapered screws, so if you overtighten them, they'll deform. 5. reopen them 1.5 turns careful to note 1/8 turn increments - use the slot as a guide. 6. restart and leave idle around where it was (1500rpm). If it's slow, crank it back up to 1500, if fast slow it down 7. If it's rich, it'll run "heavy" and slow, if it's lean it runs fast and "fizzy" and will spit 8. Settle it until it runs smooth - keep readjusting the idle back to 1500 and rebalance again 9. once happy add 1/16 of a turn open to ensure you stay on the rich side of things. 10. now set the idle back to 1000..1100rpm (Crossflow oilpumps are large clearance items and should not run enjoy Cherik http://my.voyager.net/~quadrant19/index.html

Thanks Bruce! That's a nice tool. For anyone else wondering why this tool matters.... See my gearbox page http://my.voyager.net/~quadrant19/Gearbox-upgrade.html Cherik