You take me back to my yoof days!, pair of 40mm dellortos, short duration high lift cam, standard size valves machined flat on the back as per david vizards book.
I build a similar setup in the mid 80’s. I build my own flow testing setup and used Vizard’s Mini book for insights. That was before he revealed his flat back valve hack, but raise the intake port floors with inserts. The highest praise came from from a Harley rider’s thumbs up as I passed him flat out. There is something about the bark of twin DCOE which demands respect.
Great back to back test, really impressed with the 38 DGAS. Had a few rs2000 s back in day, loved the noise of the twin 40s but the 38 was much more drivable.
I enjoy watching all the R&D, if i could afford an engine dyno ide be in there every chance i had 😁😁😁 the single 45 was very interesting to see and it makes me wonder would it be better as a open plenum manifold 🤔 you could do a nice big balance passage in the plenum to see if you can gain more up top but keep some of that meaty torque 😁😁😁
Great test, practical and useful data. Thanks for sharing Graham! The reworked head you will use will utilise the full capabilities of the 38, I think.
Great vid thanks Graham. I've asked for a Lynx test before and now you've done one. Not just a Lynx test though, a 2.1 pinto with 45DCOE , same as mine! I don't get the fuel stand off problem though with my Burton BF134 cam. I was hoping it would be better than a 32/36 and it looks as though it is. My other alternative is twin 40's which may be a little better, but possibly not enough to warrant the swap.
Lynx 45 meaty torque is probably thanks to its manifold. Cylinders paired 1-4 and 2-3 as it should be on a 4 banger. Split 45 appears to pair cylinders 1-2 and 3-4.
Did you hear the miss when running the Splits? Didn't hear it on any of the others. Hell of a jump on the mounts when starting as well LOL! This cam / head / carb /capacity matching lark is well complicated ! ! !
This is the only set ive had anything to do with but they seem to work just fine, unlike the other unbranded chinese weber i tried a couple of years ago
Another very good back to back test thanks for the information. In regards to trumpets or velocity stacks which has proven better the full radius or the 45deg. The full radius won’t fit inside the ‘small oval K&N filters part number 56-9107 filter housing’ so what is the best option. I did notice it looked like on the full race pinto you built up the Jenvy adjustable length trumpets looked to be the 45deg style and not the full radius,correct me if I am wrong. Thanks in advance 👍
Those “ jenvey “ adjustable trumpets are actually made by emerald. From testing I’ve seen and done full radius trumpets don’t work as well as a simple 45 degree flare just like Weber designed for their carbs
Hi Graham. Another great R&D Video. Is there an alternator running on the dyno engine ? Just wondering as an information if an alternator robs any power during tests.
i dont normally run an alternator, How much power one robs is primarily down to state of charge of the battery and electrical loads, if you have a fairly flat battery and lots of electrical load on a cars electrical system your loose something like 4-5 bhp, but low electrical load and a charged battery 1-2bhp
another excellent vid so, it's either a 28/36 or 45s... it beggars belief how much petrol was floating about with the lynx, that will go wrong in an engine bay... your rocker cover bolts are/were loose..
interresting how far you can get with a DGAS 38. That Ike engineering is some i did not have seen yet. Noticed however, a caugh at raised idle before power dynopull? And it sounds different, something in between a single two barrel and a twin dcoe setup. Nice video.
When I am only dyno testing different products not setting an engine up to go in a car I don’t worry about getting part throttle and progression spot on, there’s no point all people want to know is how much horsepower
ok , understood Graham. another question i am asking. Did you know of a David Brooks who developed a exotic 8 valve cylinderhead in the late 1980'ties somewhere who got as stated a 240 HP from a 2000 cc ohc Pinto? In that era as where Holbay and warrior 16 valvers where famous. Did you know about this Brooks cylinderhead ? I believe this guy is still in bizz? I could then ( 30 years ago ) bought a Holbay from a known friend, but price to high@@PenguinMotors
By that saying what you you said, "people only concerned by output" Well , teach them a lesson. because i know what counts, you do! Low down torque and a decent organic heavy springloaded clutch at best, No sinter as crazyman i do, but just on empty roads!! Wannabe enthousiast or "road" warriors, often don't know what its like to what works on road, and mixed up having a racecar goin on. Just tell the story. I can handel a solid sinterplate clutch and power down the road, but its no fun at all in traffic. Springloaded heavy duty clutch and 3500-7000 rpm OHC PINTO mainly torque 4 cyl. engine works best for fun. Just my opinion@@PenguinMotors
yes im with you, which is why i tend to start dyno tests from fairly low down, but as we are testing WOT it doesnt necsasrily represent actual light throttle driving, time is also a factor, im really short of time and for noise reasons even shorter on time when i can actually run engines on the dyno so i have to make dyno time count and tend not to bother with part throttle set up unless i have to
I seen one of those heads in Ireland...owned by one of the Nevin family and fitted to a MK2...his father had a Brooks all alloy pinto in his escort....and they could both drive them as well!@@guidorollard2944
Great test, just saved a customer of mine the expense of the splits on his road rally engine...2hp/2ibft certainly isnt worth the extra cost. Was the 38 tested with or without the "free power" spacers under the carb/between the manifold & head?
That would be really interesting, and with a more relevant cam like a 4.75 Newman perhaps?...in the middle of one now. What chokes were in the splits, if you can say?
Very interesting test. I have a Lynx manifold for an Avenger/Sunbeam 1600 and no 1&4 runners are much longer that 2&3 and was wondering if you had a very short trumpet on 1&4 and a very long trumpet on 2&3 would there be any power gain. I plan on using a Dellorto 45.
@@PenguinMotors good to know. Just swapped a 32/36 onto my 2.0 instead of the 30/34, but got some fueling issues that I'll drop on the turbosport forums soon ;)
The trumpet on the carburetor input improves the airflow into the engine ?.. The DGAS was tested without a trumpet, so not sure this was an exact comparison
Why do not you tell the punters exactly why the twin DCOE's were better up top and sacrificed some down low, then they may learn some very basic tuning principals. esp if they are looking to buy a 'supposedly' better intake manifold
