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Race Engine Building  Rating:  Rating
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 Posted: 12-12-2011 08:46 pm
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Mitch Ware
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I'm starting to figure out the budget for switching over from racing the MGB/GT and going to racing a JH. We have been building our own race engines for quite a while, but all of the little things that we have learned that let us acquire HP and longevity probably don't cross over from the MG 1800 to a 907.

We have been running historic SCCA race groups which lets us be a little bit looser with the rules than a strictly legal E Production car. Of course this means that the competition isn't quite as high since we don't have to run against miatas and integras that just rechip for more HP.

What is a good source for learning how to build a racing version of the 907, and what parts/sources/etc. are recommended?

I have a spare 5 speed and stock engine to start with. Is the getrag 235/5 acceptable? Or should we look for an overdrive tranny to convert to to gain a little top speed? How about wheel and tire sizes to get the best compromise of low end acceleration and top speed? Not to mention rear end ratios? (damn, I mentioned them.)

I'm not trying to win a national championship, but would like to build something reasonably competitive.

Thanks,

Mitch


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 Posted: 12-12-2011 08:55 pm
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JodyKerr
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I would start with the articles listed here: http://theymightberacing.com/Projects/FrameOff/JH74G/Literature.aspx

Most of these documents were written/compiled by Tim Engel who is insanely knowledgeable about the lotus motors.

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 Posted: 12-12-2011 09:13 pm
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JodyKerr
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Now, I don't know how much governing rules will impact what you'll do. I also don't know the track constraints where you'll be racing. But, if I were to build the penultimate Jensen Healey here's what I'd do:

1) Vauxhall Viva GT IRS rear end. Drops right in. Good luck finding one in the U.S. You'd have to acquire it from the UK and they're not cheap.

2) Toyota transmission conversion. Second choice would be overdrive.

3) Engine:
2.2 L crank.
Doweling upgrade as per Tim E.'s instructions
Hinge plate modification in the oil pan
Accusump oil system.
higher compression coated .030" over pistons
adjustable cam gears from Dave Bean
oversized oil cooler
front air scoop.
fibreglass bonnet
I'd get the head built/flowed by West Coast with the oversized valves.
Dellorto 45's
Delta's exhaust header.

Of course everything in the engine is balanced, etc. If I had one available I'd start with a 910 block rather than a 907.

I would also contact the fellow in the UK that had done all the brake upgrades (Martin Shirley) and beg him for a set.

and I'd set it up on 15" wheels.

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 Posted: 12-13-2011 02:31 am
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Jensen Healey
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If I were to build the ultimate JH (penultimate means second to last which is bad for racing :-)) I would contact the experts:

Huffaker racing Sonoma, CA. http://huffakerengineering.com

Also: Lind Brothers Racing,
http://lindbros.wordpress.com/vehicles/jensen-healey-racecar/

And pbahr on this site.

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 Posted: 12-13-2011 03:10 am
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JodyKerr
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Heh, I hadn't thought of penultimate in that term. I used it as any "ultimate" version will eventually be updated. :)

Jody

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 Posted: 12-13-2011 04:32 pm
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Jensen Healey
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How true Jodi!

My car is in it's preantepenultimate iteration.

Thanks for the articles!

Kurt

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 Posted: 12-13-2011 04:53 pm
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pbahr
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I have no problem with dowling the lower sub-frame in the engine, but I see the oil pan flapper as a not-needed extra cost if you have the Accusump.

Below are the YELODOG upgrades.  1500 miles on Summit Point track.  No problems mate..........well, the brakes do fade a bit after about 15 minutes !  I could not find any easy brake upgrade back when, but I think they are readily available now.

185 ft-lb,  240 hp

1.      2.2 liter
2.      Carrillo Rods
3.      J.E. pistons, 11.1 : 1 compression
4.      Lightweight Flywheel
5.      High Torque Clutch
6.      racing clutch disk
7.      Weber 45DCOE - 9
8.      COLD AIR INTAKE
9.      3” VELOCITY STACKS
10.  Custom Cams by West Coast Cylinder Heads inc.
11.  Heads Ported/Polished and flow matched
12.  Lotus "HTD" Cambelt with vernier adjustment gears
13.  Electromotive Crank-fire Ignition.  MODEL HPV-1
14.  SST 0.120” Oversize Valves
15.  Accusump 3 qt Oiler
16.  S&S Racing Headers, 4:1 merge, Ceramic Powder Coated
17.  Getrag 5 spd Tranny with Pete's Kits shifter bracket assy
18.  Compomotive 15X6 ML Wheels
19.  205/50ZR - 15 Kumho ECSTA competition Tires
20.  Spax Shocks
21.  Stiff Delta Springs
22.  ADDCO 7/8” Anti-Sway Bars
23.  Porterfield R-4 compound Brake Pads and Shoes
24.  Glasurit paint to match original Buttercup Yellow
25.  3-core Radiator
26.  50% Larger Oil Cooler
27.  Thermostat & Switch controlled Electric radiator Fan
28.  Autopower Roll bar with additional braces
29.  Driveshaft Safety Hoop
30.  Pete's Kits Engine Damper
31.  5 spd JH Rear
32.  Pete's Kits custom, single piece, stronger Driveshaft
33.  Clutch Scatter Shield

    BTW, just let West Coast build the entire engine for you, and you won't have any engine concerns, EVER.


Pete

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 Posted: 12-13-2011 05:52 pm
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Mitch Ware
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Thanks Pete, that is a good start for what I was looking for. But, of course that leads to more questions.
 
Who’s 2.2L crank?
What are the specs on the rods?
Sources for the lightened flywheel, clutch.
What are the grinds on the cams? Are they custom, or is it the 104 cams, 107’s or a combination?
Main bearings? Can the Chrysler 318 bearings be used or do I need to hunt up the vandervells?
 
I talked to Richard out West Coast at length, great guy. I will send my head out there to have the oversized valves done and all of the porting, etc. I wasn’t aware they built the whole engines there. He did mention 10 doweling the block as being almost a necessity, is there any other stiffening that should be done? I know about reducing oil flow to the head. Are there other items like that that I should know about?
 
 Mitch

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 Posted: 12-13-2011 11:59 pm
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pbahr
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Hi Mitch,

My engine is a repair (for burnt pistons) of an engine that Richard had in one of his cars.  I would have sent him my engine, but he offered his rebuild directly, with no core.

Given that history, I’ll answer what I can:

·         Believe the crank is just a standard Lotus 2.2L.

·         Rods are Carrillo Type 4.

·         Only Richard knows the flywheel and clutch info, but the Flywheel is not super light.  I did not want the instability of super light Flywheel.

·         Cam is Richards own grind:

o    Intake lift (net) = 0.4085”

o    Exhaust lift (net) = 0.4065”

o    Duration at 0.050 lift: Intake 235 deg, Exhaust 240 deg.

·         Crank bearings are Vandervelle.

I’ll send the engine build sheets to your direct email………..

Pete

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