SL-C powerplant possibility?

[Fran Hall RCR]

Henry.

It was not just the crest that created the flip with the Merc or the Porsche....both cars were following closely behind other cars....slipstreaming or drafting as they say in the USA...this created less downforce for the trailing car , and infact created lift...and at the speeds these cars were doing...200mph plus.. they actually flew ...they were obviously helped a little by the rise in the road too though...

F1 cars suffer the same problem when they draft very tightly they lose front grip due to the decreased airflow over their front wings......

http://www.mulsannescorner.com/techarticle1.htm

 

[Henry]

I just posted the first pic That came up to show what can happen and that the wing and canards prove vital at that speed. Thanks for the article, good reading.

 

[Fran Hall RCR]

The rear wing is actually very helpful for braking balance too....not just going fast...

It keeps the rear of the car planted during the forward weight transfer of braking...

Not an intuitive thought but very real and extremely important when playing at big boy speeds..

 

[Matt K]

Fran,
Have you heard of any SLC owners pushing their cars close to 200 MPH? I know you said a while back that you thought 650 hp would get the SLC to 200. Do you still believe that or do you think more/less power is needed?

 

[Kyle]

Why does everyone think you can just throw a 1600 hp engine in a 2200 lb car and not die? People have equivalent power and weight in highly dedicated drag cars with big race slick and a full drag suspension and lose control and crash or die, so how they hell does someone plan on hooking with street tires and much less skill than a professional drag racer? Please people, be realistic! This is life, not some video game where you can smack a wall at 170 mph and back off then slam in to a wall head on and be perfectly fine, you can crash at 40 mph with a 200 hp car and be dead, I promise 99.9% of people who try to race a car with a 1.5-1 lb/hr ratio would die if they tried to race, dropped a gear and got on the throttle... Please people, try to think!

 

[Michael]

Why does everyone think you can just throw a 1600 hp engine in a 2200 lb car and not die? Please people, try to think!

LOL!!!! I've been asking myself the same question for a few years now. I think it's just the same old story... "Mine's bigger than Yours"...

 

[Henry]

I think people lose sight of the weight of the car and are used to 3-400 hp/3-4000 lb cars. Anything north of 600 hp is approaching the line of question. With that said there are high HP supercars that are completely tame with the aid of traction controls. Well to a limit I should say.

 

[Josh]

^Exactly, with aids. I agree completely....600 hp is crazy, at least on the street, in a car as light as the SLC.

Speaking of crazy power, how about a 2jz? A little heavier, but with the stock snails and a few simple mods, they push out 500 hp which I think would be great in an SLC. Make it white with red graphics and you have a winner.

 

[Yos]

I guess I'm in the minority here, but I'm glad that people are pushing the HP boundaries.

20 years ago 5.0 Mustangs had 215hp, and were pretty fast...not to mention dangerous as hell. Should the Ford guys have stopped there?!

I thought this was a forum about fast cars...

 

[Josh]

^No, don't get me wrong....I enjoy watching it and am still happy it is being done. The majority of the pushes today are due to the weight of our cars ballooning due to safety standards.

For me, I personally would enjoy more manageable power in the SLC as I would tire fastly with feathering the accelerator to avoid spinning. For me, top speed matters little. I am a handling and acceleration man, addicted being pushed back in my seat. I am, however, enjoying watching your LS7 build.

 

[Mesa]

Well, HHhmmmm... people don't die racing vehicles with a 1.75 lb per HP ratio, so it is possible to survive such things. Although I would be concerned if the builders with a billion HP were fresh off the video game circuit. That might be a problem - good thing is that not too many people young enough to be vidiots are wealthy enough to build such a car.

Truth be told 200hp cranky roadrace bikes are not much fun on the street, plain and simple they are way too fast to enjoy, first gear often exceeds the national speed limit....tedious and boring.

It was important that my engine be boost adjustible so that it might be possible to drive the car in a mellow fashion and enjoy it at that speed. Then when it is time for the track, dial up the boost to more demanding levels, we shall see how this works out. For now it continues to be a technology excersize, we might be able to have our cake .... or maybe the cake will be all over our faces.

 

[Dave]

Bunch of pu$$ie$.
This is what you need in your SL-C or gtfo. I bet even Alex would consider turbos after this....
3100+ HP BBC twin turbo - YouTube

 

[john b]

I think the standard for the SL-C has been very well established last year by the achievements of Ryan Ellis and the SL-C 01 race car. Did everyone here forget that this car won every Super Unlimited NASA race that it finished while also setting new track records and winning the Super Unlimited Championship finals by over 8 sec????

Look at THAT car's powerplant! How is that car not enough? As Fran always often says,.. it's about making a completely BALANCED sportscar.

It's not about making Frankenstein monsters that will only scare small ignorant children who don't know better. Make a car that the real sportscar racing professionals will respect.

If I were making a new SL-C, I would choose the the LS3 or a NA LS3 or equivalent. I have a custom LS7 in my car, only because the engine was completely custom made, it came in the car, and the car was put together by a reliable racing group, and the price was right. ( I do know that many of the SL-C's here are being put together with even better skill and intelligence. So many of the guys here are really really amazing!)

The one thing I believe in 100% is that if 500-600HP is insufficient in a 2200 lb. SL-C on the track, the problem is ME, and I solve that by going to more racing schools and increase my hi-performance driving understanding and skills level. That's the performance gap. NOT the HP.

Guys,.. the SL-C performance standard has already been established. It's completely balanced, and it works!

 

[Justin]

I believe Mesa said it best when he said, "Five to one power to weight is the best way to go."

That's going to be my plan (LQ9 with basic bolt ons). My SLR is 5 to 1 (when it's running correctly-damn LNF!), and it's frighteningly fast!!! Everything gets blurry when you press the go pedal. My track instructor told me that the SLR would almost run with a Radical if it had the right tires and aero package (needs a front wing... The rear end is planted!).

 

[Henry]

^LQ9 all the way

 

[Troy Truglio]

I just watched some more video of the Honda HSV-010. That has a V8 that is 3.4L and the same bore as the LS376 so it makes me go hmm. It does have a rev limit of 10,000 though. I am still pondering the flat plane crank LS376. Maybe in the 4.0L range and build up the valve train to rev to 9000rpm. So custom crank about 3k, custom cam 1K, custom rods 1K, valves, spring, retainers, solid lifter conversion maybe 2K. I think the stock ECU can run it with a rev limit increase and proper wiring. If not stand alone then. A 8-4-2-1 header design and a sick sounding high reving motor for maybe 500hp. This is what I ponder sometimes and maybe a future build. Who knows.

 

[Scott]

I believe Mesa said it best when he said, "Five to one power to weight is the best way to go."

That's going to be my plan (LQ9 with basic bolt ons). My SLR is 5 to 1 (when it's running correctly-damn LNF!), and it's frighteningly fast!!! Everything gets blurry when you press the go pedal. My track instructor told me that the SLR would almost run with a Radical if it had the right tires and aero package (needs a front wing... The rear end is planted!).

Just out of curiosity, why the LQ9? Cost? I tried looking for someone selling new crate LQ9's (not shot blocks) and came up empty.

 

[Justin]

I would get a used engine. They can be picked up with the ecu, gas pedal, etc for a grand with low mileage. A couple grand later and it will produce 400-450 hp (on the conservative side).

 

[Roger]

Just out of curiosity, why the LQ9? Cost? I tried looking for someone selling new crate LQ9's (not shot blocks) and came up empty.

Yes, they look difficult to find. Googling with the part number (12491857 from here) got me City Crate Motors who say "Available new or remanufactured". I've never researched them or used them.

When the time comes (hopefully before I die ..), I'd be tempted by an LSX with twin turbos.

 

[Henry]

Just out of curiosity, why the LQ9? Cost? I tried looking for someone selling new crate LQ9's (not shot blocks) and came up empty.

There are tons of them out there and they are cheap reliable engines. Plus if you swap the heads for L92 heads from chevy trucks, custom cam, and L76 intake you will get 500+ hp for 4-5K.

Here are a few articles that explains more:

http://www.gmhightechperformance.com/tech/0702gm_ls2_engine_l92_heads/viewall.html

http://www.carcraft.com/techarticles/ccrp_0705_chevrolet_ls2_l92_cylinder_heads/viewall.html

http://www.silveradoss.com/forums/topic/66146-2004-lq9-l92-heads-l76-intake-cam-build-up/