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Discussion Starter #1 (Edited)
This is the beginning of a long post in my rebuild and attempt to build a 400HP Naturally aspirated Jalpa that will redline at 10K .Here are pics of the motor out. Everyones input is welcome. I see no reason that with custom made 4 valve heads, Carillo rods , titanium valves and retainers and block reinforcement that it cannot be done. We Shall see.
 

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Discussion Starter #3
The problem is that it has sleeves. They are not that thick to begin . I would have to machine the block to accept larger sleeves then have sleeves made. I can bore the existing sleeves slightly but this only yields a small increase in displacement. My lathe is not large enough or precise enough to turn a set. It is an interesting idea. I will measure how much displacement I could gain from larger sleeves , They would probably cost 4 or 500 each. If I could gain 1 liter total it would be money well spent. That would be good for probably 75 to 100hp. Combine that with the ability to have larger valves, more head flow and increasing the rpm it could push me well into the 400s without having to turn more than 9K. Here is the math
Current output 275 HP (From Dyno)
Increase displacement 30% 85 Hp
Raise rpm to 9 to 10 k and move power band up higher 20% 70HP
4 Valve super high flow heads 25% 80 hp
Obviously all numbers are estimates but it seems very possible. If I don't add the displacement , I still think 400 is possible. But with displacement...….
Who cares if it sounds like a formula one car LOL
 

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Discussion Starter #4
Jalpa Formula one project

I went to the Frankenstein engine dynamics yesterday. They build custom heads , intakes, etc. We looked at the Jalpa heads. He believes we can build a Jalpa motor that will produce from 450 to 500 Hp and turn 10K . I am engineering a replacement system for the water pump, alternator and distributor drives. I am going to put dual distributors on the cam ends and run dual coils. (that will provide plenty of separation and time for coil charging on a 10K motor.) I am fabricating a shaft in a housing that runs off a belt from the crank pulley and drives the alternator, water pump and oil pump on the other end of the engine. (basically a high speed jackshaft)This will take all the stress off the cams and chains and allow the engine to rev faster. I think we will make four valve heads with titanium valves. I will post pics as I do it. I am buying material tomorrow. Lee
 

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Discussion Starter #5
Jalpa jackshaft

I bought everything to make the jackshaft today and started fabrication. It should work really well. . The alternator and water pump will be on the back of the engine driven off the crank via jackshaft. The Distributor will de driven directly on the cam. (It puts very little load on the cam)I got forged pulleys and high speed bearings good up to 15k rpm.
 

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Discussion Starter #6
I found a supplier that can make custom sleeves for 180 each. I have sent off my piston and rod to Carillo. I think I can manage a 92 mm bore to get me over 4 liters. I am planning a lot of measuring this weekend to see what the limit will be . I plan to replace the block spacer with a cnc machined insert that extends the block and holds the sleeves to replace that steel piece of crap there now. Attached are pictures of the jackshaft I am going to use to disconnect the cam from the distributor,water pump and alternator
 

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Discussion Starter #7 (Edited)
Jalpa valvetrain revelations

In my quest to build a high revving Jalpa , I have made some amazing discoveries. In order to turn really high rpm you must either have a very stiff spring or very light valve components or both. (The problem with really stiff springs is that they tend to destroy the valvetrain)The stock setup with the manley stainless valves is as follows (Both intake and exhaust weigh the same:
Valve 93 grams, Lambo stock bucket lifter 75 gr, Shim from 31 to 38 gr depending on thickness. Titanium retainer 17 Gr and keepers 3 gr. This is a total without spring of about 220 Grams. (not far from stock weight) This setup allows me to easily turn 7500 rpm using a Crower spring number 68406 with an open pressure of 380 lbs. However going from 7500 to 10 k is a substantial jump. I figured a way to cut the valve train mass to half . This should allow all the rpm I dare turn. I am going to put bushings in the lifter holes and run 31 mm shimless performance lifters (I am shopping all my options) They weigh only 28 grams total. I will use a smaller od Beehive spring with about the same open pressure. The retainer is only 7 grams and titanium valves weigh about 65 grams each, That should put my total moving mass excluding the spring at around 103 grams or under 4 ounces. That is less than half what it is now and I will not have to fight to find shims. That is very light. I do not expect valve float past 10K rpm. I am removing all the drag on the cams so the whole assembly should rev like a formula one car. I will post all the specifics once we work out the exact lifters etc.
 

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Discussion Starter #8
I spoke with WEB Cams out of California and they can hard weld and regrind the cams both increasing lift and extending duration. I am packing them up to send off tomorrow. They came highly recommended by Carrillo. I will post the specs on the stock cams and what the proposed regrind will be as soon as they profile them. Really nice people. 10K here we come. Lee
 

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I spoke with WEB Cams out of California and they can hard weld and regrind the cams both increasing lift and extending duration. I am packing them up to send off tomorrow. They came highly recommended by Carrillo. I will post the specs on the stock cams and what the proposed regrind will be as soon as they profile them. Really nice people. 10K here we come. Lee
Interesting, they are only 20 miles away from me and I just received my reworked Espada cams with all lobes rewelded to factory specs (actually to a master they had for a Jarama) from them. They look good.

What happened to your 4-valve plans?

Laust
 

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Discussion Starter #10 (Edited)
The company going to make the heads let me wait a month without even a quote and then talking 6 months, more money (over 30K) . I think they really did not want the project unless I paid a ridiculous amount of money. If I spend the money on cams, rods, pistons , titanium valves etc, I may still get close to 400 Hp. It will only cost me about 12K . I am cutting the valvetrain weight in half, increasing compression , displacement and RPM. The math says I should get close with the baseline numbers I have. Plus Carillo is designing the pistons and rods for over 10K RPM operation and 600 HP. I want a formula one Jalpa .Displacement is 10% more so 275HP x1.10 is 302.50 x 10% for compression about 330 HP then raise RPM another 2 to 3 k. Probably 60 or 70 HP. So it is entirely within the realm of possibility to hit 400. Lee
 

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The company going to make the heads let me wait a month without even a quote and then talking 6 months, more money (over 30K) . I think they really did not want the project unless I paid a ridiculous amount of money. If I spend the money on cams, rods, pistons , titanium valves etc, I may still get close to 400 Hp. It will only cost me about 12K . I am cutting the valvetrain weight in half, increasing compression , displacement and RPM. The math says I should get close with the baseline numbers I have. Plus Carillo is designing the pistons and rods for over 10K RPM operation and 600 HP. I want a formula one Jalpa .Displacement is 10% more so 275HP x1.10 is 302.50 x 10% for compression about 330 HP then raise RPM another 2 to 3 k. Probably 60 or 70 HP. So it is entirely within the realm of possibility to hit 400. Lee
Thanks, that makes a lot of sense.

Have you thought about doing simulations for some of the design decisions?
I have used this package https://performancetrends.com/Engine-Analyzer-Pro.htm for my Espada and Jalpa, mainly for finding optimal cam timing. Unfortunately I only borrowed the program and no longer have it.
 

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This is turning into some impressive engine work. What is the plan for tuning and fuel/air?
 

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Discussion Starter #13
I plan to run the Webers and will re-jet as necessary for optimal performance. I am going to custom build a distributor or 2 for the ends of the cam or cams. My old Ferrari used a single two level distributor mounted on the end of the cam to maximize spark separation. I will either take two 4 cyl distributors and modify them to mount on the end of each cam or get a single dual stage double coil distributor on the end of 1 cam. I have to see what is out there that is capable of 10K . At really high RPM the separation between sparks is important due to the high turning speed. That is why a lot of high RPM motors have such large diameter (or dual)distributors. Also coil charge time would be really short for a single coil setup. With dual coils, there will be double the charge time. I have even looked at magnetos. I may even completely custom build a pair.(I love fabricating) I can probably find something I can modify and save the work. The idea is make this a car that uses 1980s technology (except the rods and pistons) and has huge HP for its displacement. I will make badge in Lambo script that is SV or especiale or prototipo or something like that. I love it at car shows when "experts" know all about your special edition and proceed to tell everyone that walks up hpw rare the car is. LOL
The idea is to build what the Japla should have been.(A 10 k RPM 400 HP supercar) Imagine what the Jalpa sales would have been configured like that.Plus the engine will look pretty original. Heh heh heh. I don't have any software to model the changes , just baseline dyno data ,lots of Hot rod experience and average increases for the type of changes I am making. We shall see...………. Lee
 

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Discussion Starter #15
I went way beyond that. I fabricated intakes with injector bungs, cut notches in the balancer to use a hall effect sensor and fabricated a full set of turbo intake and exhaust . I even spent 2500 on a turbo. The problem is that if I change it to electronic with a computer, I am fundamentally changing the era of the technology. I like the idea of a stock looking Jalpa motor with webers that will scream at 10K and run webers. I am very adept at jetting and tuning them. They are almost as efficient as fuel injection. Ignition would obviously benefit from tunable curves but I think I can get it pretty good with the ideas I have. I just like the challenge of doing something no one else has ever done. At 9500k rpm the Jalpa should hit close to 200mph without gear changes.Once I get mine in the 400 hp range, everyone will want to do the conversion. I don't think it would hurt resale at all. Also, with HP increase instead of torque, I don't have to worry so much about fragging tranny, axles, etc. With the turbo setup , I was going to almost double torque. That could break lots of irreplaceable parts. However, when I finish, I am specifying the rods to handle 10k rpm and 600Hp. I can always boost it and convert later.
 

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Discussion Starter #16
Cam Decisions

I got back the cam profile today from the grinder for the Jalpa. The stock cams are really pretty mild. They only have 224 duration at .050 and total lift of .395. That means effective lift with valve lash is .383. I plan to increase base lift to .435 or .440 and extend duration by 24 degrees. That should raise the powerband substantially and drastically increase hp in the 5 to 9k range. I even considered a 262 duration cam at .050 but that is pretty radical and would have to idle very fast probably 2K . I am already going to need a vacuum pump for the brakes and will idle in the 1600 range. It will lope like a drunken politician on debate night but I like the sound of loping. I am going to increase the compression to 11 or 11.5 to one to offset the radical cams. I just hope it is not too peaky . With a standard I should be ok. I hate running low rpm anyway. I will let everyone know when I make my final pick. Any of your experience with regrinds would be useful> Lee:cool:
 

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Discussion Starter #17
Dyno sim

I bought dyno sim 6 and am running combinations. It was very close on the original dyno numbers based upon my inputs. It looks like with 11.5 to 1 and 9000 rpm I can make 450 HP . Yes you read that right . A 10 k rpm 450 HP Normally aspirated Jalpa. I will post the results when I finish all the simulations.
 

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Discussion Starter #18
I ordered the cams today from WEB racing cams. After many hours running dyno sims , I settled on a 254 degree duration At .050 with .435 lift. Sims show pretty good torque from 3000 up and HP above 400 from 7500 up to 450 at 9,000 . Is anyone even reading my posts ? I thought everyone would be interested in the project. Lee
 

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Did you order 4 new cams using new blanks or a weld/build-up and cut on your present cams ?

Paul
 

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Discussion Starter #20
Hi Paul,
I went with the weld regrind since it will save some money and I will probably never use the stock grind. (They did profile it so I can always go back to that)Blanks would have cost me about 5 k. My rods alone will be about 400 each. Titanium valves are 140 each. I figure I will have 12K in the build by the time I am done. If it makes 400HP I think it is money well spent. Plus what fun. Have you ccd the stock chambers. I am around 40 or 41 but Carillo thinks they are 35 CC. I measured using a lexan sheet and a hole with a cc syringe. The syringes (for horses) are usually pretty accurate. Probably on par with a pipette. When I cross checked the math, the stock CR stroke, bore and head gasket was giving similar results. About 40 or 41. I am going to double check this weekend. I am ordering pistons Monday and want 11.5 to one compression to offset the long duration cams. I should still be able to run pump gas on that. If anyone has ordered domed pistons, what was the CR and dome CC size. Lee
 
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