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Jensen on the Race Track!!!!  Rating:  Rating
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 Posted: 04-26-2006 01:16 am
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Ron Earp
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Well, we got the Jensen out this weekend for the first test day it has ever been on.  We didn't really intend to race the Jensen since we knew we'd have problems.  We just wanted to get out and shake the car down and find out where the problems were.
 
First session out we made it about 3/4 the way around Roebling Road and had a fire! The header wrap, which was soaked in oil form engine run in, finally got enough temperature in it to light the oil off.  So, into pit road we go, trailing black smoke and flame, to get it extinguished.  Driver was shaken but little damage done.  We spent the next couple of hours getting the wrap off and washing off all the fire retardant in the engine compartment.
 
Second session we got a few laps in but the water temperature wouldn't stay down.  It'd get up to about 210 or so, oil temperature the same, and I'd bring it in and shut her down.  But, the laps I got in were good! Car cornered flat on 650lb springs and turns in sharply with low steering effort despite the 225-45-13 Hoosier race meats.  Welded rear and panhard rod were planted solid as a rock, scary planted actually.  I think this car will acheive some high corner speeds if she'll hold together.  In short I liked it!
 
The third session was missed but we did get out the fourth session to collect more data.  The engine Judson built pulls very smoothly and strongly and I was able to get in a couple of 80% laps running the car to 6500-7000 RPM.  I've only driven one other JH, one with some sort of Paco stage two motor with Delortos, and this Stromberg carbed motor I have will walk all over that thing, no doubt about that.  Torque was surprisingly pretty good throughout the rev range and top end power decent.  I had it on the straight at 6000 RPM in 5th and it still pulled pretty good when the hammer was dropped, and at that point we're doing like 110-115mph or so. 
 
The engine needs more sorting - carbs out of sync, timing is conservative at 10 BTDC, and we've not optimized cam timing, porting, etc. - this is just a first effort to get the little guy on track.  But I am happy, Judson's motor is holding up well and I think will do the job!  The engine has 75 psi of oil pressure at idle WHEN COLD, but once temps get up around 210 F we only get around 30-40psi at 3000 RPM and I don't like that.  The oil pressure stays high when the temps are around 160-180F, but above that they drop off and drop hard. We also have some flicker on the gauge in long sweepers so we need some oil protection. I don't think we did any engine damage because I didn't hear anything bad and the lowest I ever saw, when bringing it back in hot at idle, was 15-20psi and that is about par for a 907 engine. 
 
What we learned we need to fix is the following:
 
*More radiator - I've ordered a big aluminum radiator for a Ford and will make it fit for more cooling.  That means I'll have a super nice 4 core brass stock one (converted to four core) for sale if anyone wants to upgrade their cooling system.  It'd work great for a street car, but not for a race car that will spend 30 minutes at 5000-7000 RPM.
 
*More oil cooler - I tried the stock cooler but it isn't enough for race duty. If I can keep the oil cooler and maintain good pressure I'll be a lot happier driving the snot out of the car.
 
*Plumb Accusump for some oil safety in the turns.
 
All in all I am pleased.  She weighed in at 2290 lbs with a 195lb driver (not me), so with me it'll be about 2260lbs with half tank of gas, just about where we want it since spec weight is 2240lbs. I plan to knock these issues out and have it back on track at VIR in two weeks! Here are some pictures:
 


Last edited on 04-26-2006 01:24 am by Ron Earp

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 Posted: 04-26-2006 06:17 am
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Jensen Healey
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Congrats Ron! Sounds like a blast. I'll just live vicariously on my couch.

Keep the reports coming,

Kurt

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 Posted: 04-26-2006 07:34 pm
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Brian Kelly
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Since this remains out there for public consumption (and at this point has been viewed 41 times) I feel I must comment:

you said…..
“I've only driven one other JH, one with some sort of Paco (PAECO) stage two motor with Delortos (Dellortos), and this Stromberg carbed motor I have will walk all over that thing, no doubt about that. “

Since I’m the one who so kindly allowed you to drive “that thing” I’d like to mention that when you drove “that thing” it was and is still in a state of untune.  I have not had the time equipment or resources to dyno and tune it properly.  It does however run well enough to put a smile on my face.

When you post info for public consumption please try to be more considerate of those you choose to mention.

 “walk all over that thing”   Yes, I am offended!

Brian

Last edited on 04-26-2006 08:18 pm by Brian Kelly

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 Posted: 04-26-2006 08:17 pm
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Ron Earp
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Brian, again, I definitely didn't mean anything negative by the use of "that thing".  In my Southern vernacular that is the way I speak about things in general and didn't mean any offense. 
 
However, since it appears you will not let the issue go, per your email this morning I do take offense at being called an "a$$hole" for the comment.  As I replied this morning in my email to you at 921AM:
 
-----
Brian,

My wording of "that thing" is not meant to be negative toward your car and I wish you wouldn't take it that way.  It is just the way I generally speak about objects.  If it really is a horrible thing to say I'll change the post to "that car", your car, or whatever you like.  Your JH, as I mentioned on the forum last year, is the nicest one I have ever seen in person, flat out beautiful. 


Simply because we disagree on what makes a good motor for a car isn't a reason to call me an a$$hole, at least I don't think. I'm not a bad fellow and generally very helpful to any gear heads in the area any time that I can be.


Regards,


Ron


----


Again, I apologize if I've upset you with my choice of wording.  It was not my intent at all.  My intent was to simply indicate a couple of things:


*Stromberg motors are oft times maligned, to the point where people unfortunately write them off as not being able to produce power


*It does not take an expensive motor build to produce a 907 that makes good power, it takes a good builder with a good understanding of matching things up who doesn't necessarily have to be the most expensive or best known.


I'd be happy to help and tune your motor and help out with dyno runs, as I told you last year.  I'm in good with the two local dyno shops and will get mine over once I do the radiator and oil cooler fixes. You are welcome to bring your car too if you like and I'll be happy to assist with the work. And you're welcome to drive my car if you like.



Best,



Ron

Last edited on 04-26-2006 08:38 pm by Ron Earp

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 Posted: 04-26-2006 08:39 pm
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Brian Kelly
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What was said in private should have been left in private.  This is a fairly small community and when you mention my car publicly I must respond.  That's all. I'm sure others would have been offended had you referred to their car that way.  I’m not trying to make a big deal about it I just don’t want my car to be shown in a bad light. Your car looks wonderful and I’m sure it’s a blast to drive.  I am sorry that my temper faired this morning but when I see the number of hits on your post increase my blood pressure goes up. All I was asking is that you be more considerate of others who may be reading this list.

I’m sorry to have detracted from joyful occasion.  You should be proud of what you’ve done.  I’ll cool down now.

Brian

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 Posted: 04-27-2006 05:21 pm
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Ron Earp
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It is small, but as such we all need to get along - in 20 years there won't be many of us and we'll need parts! Both of us, that is the people and the cars. 
 
Again, sorry if my wording caused some problems but the folks should know you've got a very nice JH and the motor is fine too.  My car is different, a ratty car just for racing, and the motor is built that way as well - functional, barely, but not nice.  Everything looks good at 20ft - come no closer!  It does run well and has the advantage of light weight, open exhaust and headers, ported head, re-worked strombergs, 5 speed tranny with 4 speed rear end, and a welded rear that doesn't break traction putting power through slicks. 
 
I think there is more power to be had though through fuel and timing tuning on the dyno as well as cam timing (that is a can of worms!). And, now the motor is running and things seem okay we'll be taking it to the dyno to get her setup.  You are welcome to bring your JH too and we can tune it as well, nothing beats a dyno to find out what works and what doesn't. 
 
The motor surprised me somewhat for drivability.  The only other Lotus engine I'd owned was the 2.2L turbo in my Esprit and it is another ball of wax entirely.  This thing had a surprising amount of low/mid range torque which I didn't expect at all.  I really thought it would be gutless til about 5k and then produce some power and peter out around 7k or so.  But, it really feels powerful from about 3500 to about 7000, maybe 6800 or so. And this might be a good thing because I HATE this 5 speed.
 
The ratios in the 5 speed are fantastic - close, 1:1 5th, great for a sporting road car, or race car.  But the shifting is like shifting a wooden dowel plugged in some mud - no positive engagement, very loose shifter, very vague feel.  By contrast, the 4 speed I drove in Judson's car with this motor was great - positive, very tight, nice feel, and shifted well.  I'd just hate to give up one gear, but, if the engine can be torquey (well, as torquey as 2L get) then it might live with a 4 speed.
 
I have a 4 speed downstairs and it also feels positive and good.  Anyone have feedback on the 5 speeds and feel? Are they all this way? Mine drives well, doesn't make funky noises, but this thing is definitely not a "nice" shifting tranny.   Might have to put the 4 speed in for racing since they are plentiful and the 5 speeds are worth money, and money allows racing.  And no, I can't run any tranny that didn't come with the car but with the number of Jensen Healey's racing in ITS, 1, who would know?  No, can't do that.
 
Anyhow, I'm impressed with the little JH.  We've still got a lot of sorting to do but my track time with it, however limited, didn't make me want to quit trying to race it - I think there is potential there (naturally, but remember - SCCA racing has changed a lot in the last 10 years and the White Lady might not fare so well these days) but it'll require a lot of development.  Still, it takes a lot of energy to make this thing into a race car - I swear, it would prefer to lie in a field and rust away, or maybe sit outside on a Sunday at a car show.  But, we're going to make it race anyhow!
 
R
 
 
 

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 Posted: 04-27-2006 06:23 pm
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Mitch Ware
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I got a call last week, a local guy wants to know if I'm interested in buying his E Production JH. hmmm, how could I explain its sudden appearance to my wife.....

Mitch Ware

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 Posted: 04-27-2006 06:42 pm
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Greg Fletcher
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Since I'm the moderator I'm going to put my 2 1/2 cents in here- it's all been said before; I think it's very easy to misread what someone else has written and either imply or read something more into it than may actually be there or intended, as demonstrated by the ridiculous posts I've been having with Tim Engel recently. What can I say? I know how easy it is get defensive of my pride-and-joy and no one wants to get rolled under the bus, but we happy few are tiny in numbers and it certainly behoves us all to blow off the lame comments and I suppose in my case, just suck it up once in a while for the benefit of the group. Besides, I don't have time to dissolve Parliament and declare martial law.

This is all about sharing information to make our hobby more pleasant, hopefully save some money and have fun. I'm sure we can all agree on that.

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 Posted: 04-27-2006 07:45 pm
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Ron Earp
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I've spoken with him before,  I think he has moulds etc. too to do fender work etc.

One thing that is interesting to ponder regarding Production (Prod) and Improved Touring (IT) - mod and prep level in IT is now ahead of where Prod was back in the 70s.  IT has really become a wide open test bed of ideas with anything that doesn't involve the motor per say.  Prod has liberal rules on the motor that IT doesn't, so, folks can run their 14:1 compression Spridget and blow it up every third weekend. 

IT doesn't allow the crazy motor mods, but is free on suspension/chassis - so spherical bearings are used extensively, lots of shock/spring tricks, etc - but the motor is relatively stock with only minor porting, 0.5 compression hike, free exhaust, etc. That being said, there are a lot of tricks and attention to detail on cars - who would have thought a legal 240z could put 180 hp to the wheels when the car was only rated at 150hp at the flywheel? 180 rwhp happens in IT, and it is legal.

What I'm trying to say is if the Prod car he is selling is old, then it has little chance to be competitive today in Prod or IT.  Similar to my comment about Huffakers car, it did come out and win in the mid-90s, but, coming out today would be a different ball game.

If you have a lot of cash and want to race with the same five guys every weekend, go Prod.  If you have similar or less cash, but want to have heavy competition and large fields to race against, go IT.  Prod is cool, but Prod cars and numbers have taken a heavy hit because they appeal to a limited crowd - not everyone thinks a British 1970 Whatsamafloozit is the pinicle of racing.  As IT got popular, and now Spec Miata (don't laugh until you've raced one, and then you won't laugh) Prod really has a low subscription group these days and each group, D, E, F, etc. generally has less than five members at a track on a weekend.  Not exactly a big field.

But, no matter what, getting some seat time in something is what counts!

Now, the JH is the lightest car in ITS, where it races, but we're going to need about 160 rwhp to really be in the hunt. I hope we can get it, but I've yet to see any solid real world data from a Dynojet on a Jensen motor.  Anyone else seen any?

Ron

 

Last edited on 04-27-2006 08:00 pm by Ron Earp

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 Posted: 04-27-2006 08:47 pm
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Mitch Ware
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I understand what you are saying RE prod. I just got my SCCA license last year and drove a '68 MGB. I will driving it again this year. There were races last year where it was me and 4 Acura Integras. The MG really didn't stand a snow flake's chance in hell of being compettitive, but I had a lot of fun. Probably once I get enough seat time in, I'll start worrying about where I finish instead of just finishing and improving my lap times. However, it is still a hoot!

 

Mitch Ware

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 Posted: 04-28-2006 08:36 am
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Harkes
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Hey Ron, fantastic news. I'm sure you 'd make all JH owners proud esp. when you start finishing in top 5.

About the stromberg/dellorto peaco stage II discussion... if you'd could help Brian out with tuning his car on the dyno which was very generous of you to offer then i'm very sure that his engine will be very hot!!  having said that and to bring back some humor: imagine what your engine could do when slapping on some dellorto's...

do they allow you to run the JH with dellorto's (since it came on EUR JH's), probably not.

Isn't your sump baffled to protect the engine from oil surge? Accusump will definitely work (yellow dog? has installed one i believe)

good luck and i look forward to pictures/reports and if possible some film?

cheers

erik

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 Posted: 04-28-2006 09:00 am
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Harkes
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Ron, one more thing regarding your troubles with your 5sp gbox. I'm assuming you are running the getrag box. As i mentioned Yelodog's accusump...the bright yellow JH (check out http://www.jhppg.com/album62 earlier, the very same guy runs the getrag box too but with improved shifter bracket assy!

now i think you can get this getrag shifter bracket assy from Pete's Kits, who also sells the improved engine damper kit...

EDIT: i found Pete's Kits webpage for you: http://jhppg.com/pk0604.htm

this might work for ya

cheers

erik

Last edited on 04-28-2006 09:03 am by Harkes

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 Posted: 04-28-2006 03:14 pm
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Ron Earp
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Thanks for the help there! I did do a similar repair on my 5 speed, but it isn't the play in the lever/bushing, it is just a general vague feeling and no positive engagement.  Might be related, but I'll drive it a bit before doing anything about it.

The pan is baffled and I do have an accusump, but the accusump was not plumbed this time out. It will be next time!!!! 

Roebling  has a long right hand turn that is three turns, but the net result is you'll pull high g turning right for like 15-20 seconds. Even good baffles, which I don't have, don't particularily like this setup.  Onthe other hand, stock Mazda Miata oil pans have no problem with it whatsoever, but design has marched on since the early 70s.

No dellorto's in IT.  In fact, I'm convinced you don't have to have them for high power build.  I think they will help for throttle response, but, for pure hp/air flow I don't think they'll add any peak hp over the Strombergs (properly setup and jetted, ported manifold, and water bypassed out of the blasted manifold). 

The twin 175 Strombergs are plenty big enough for a 2L or 2.2L motor. We are forced to use them on my partner's raing TR8 at 3.5L and there is plenty of flow to support that motor with more hp and torque than we produce using the JH motors.  We're learning how to tune them properly and I feel they are somewhat used as a scapegoat for other issues with the 907s.  Don't get me wrong, I'd rather use dellortos or Webers for throttle response and ease of tuning, but I don't think they are a magic hp fix. 

We'll see if my theory is right once we get some dyno numbers, and if Brian brings is out to tune as well then we'll have some godo solid back to back numbers same dyno, dame day, etc.  Although I suspect his motor tuned is going to produce more peak hp due to cams/compression/size so it isn't a true comparison of what Dellortos vs Strombergs can do.

Ron

Last edited on 04-28-2006 04:32 pm by Ron Earp

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 Posted: 04-30-2006 07:27 am
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Harkes
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i think you are right about the dellortos/strombergs: i think it is the throttle responsiveness and not so much an increase in HP. If there would be any, then we are talking 5HP or so, but that is hard to notice.

i have some dyno figures from my new 2.2 engine, but that won't help you in your comparison either. I will scan it and post it none the less next week.

my 2.2L engine has 10.9:1 compr, JE pistons, lotus x drilled crank, 104/107 cams, ported head and inlet manifold and 45mm dellortos with 38 venturis. Output is around 215 BHP and around 185 lbs/ft torque at around 5500 rpm.  This is out of my head..

i will still run with the 13" stock wheels and current tires (185x13x70)

good luck with sorting out the gbox and good luck in racing your fine JH.

erik

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 Posted: 04-30-2006 12:07 pm
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Ron Earp
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The hp figures are healthy and if on the mark would be really strong, but the torque suprises me even more, at around 84 ft/lb per liter! 

Getting more than around 80 ft/lb per liter is extremely difficult to do with a motor.  Even very modern 4 valve designs using variable camshaft timing and/or variable valve lift, such as the E46 M4 3.2L 4 valve six is at 81 ft/lbs per liter and Honda's S2000 2L 4 banger Wondermotor is at 81 ft/lb per leter too. 

Most 4 valve engines, like say an arguably less technically advanced 4 pot like the Yamaha designed  2ZZ-GE built by Toyota and used in the Toyota Celica as well as the Lotus Elise/Exige puts out around 122 ft lbs with 2L, or about 60 ft/lb per liter.  Nice write up on those motors here and the reason I mentioned it is I've been looking at it since my racing buddy Jeff has ordered a new Lotus Exige, lucky dog. http://www.sandsmuseum.com/cars/elise/thecar/engine/toyota.html

Are your dyno plots from a engine stand type dynometer? And what sort of SAE procedure were the numbers taken under, it can make a big difference.  I don't supposed we'd be lucky enough to have rear wheel hp/toque figures for the combination? If the little Lotus 907 will produce torque at levels of 60 ft/lbs per liter I'd be pretty happy, but really excited if it'd produce more and I'd need to duplicate some of your combination pronto (might be a little cheating there!).  I imagine my output will pale to yours, but without a common procedure between the methods,  comparison and conclusions will be difficult to make.

Last edited on 04-30-2006 12:23 pm by Ron Earp

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