wanting to boost LS7

parker@gearone said:
Should I throw some dish style pistons in there to lower the compression, Lowering the compression should allow me to turn the boost up safely. by the way I am already tuned and set up for e85 and there is e85 on the pump 2 miles from my shop (tests at e80 - e90) $3-$4 a gallon 
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the Ls7 if you kept it stock is 11.1 compression  and that sound high - but cam design and incredible quench design of the heads prevent detonation better than any other LS  -  On pump you will Not be able to go over 11Lbs boost - even if you went to 9:1  - you could just run more timing (more power).  But since you are e-85.... e-85 is a wonder drug for Boost - not only is it 110 octane (likely) but its also got incredible cooling  - its more efficient than any heat exchanger and most intercoolers ... so you can crank up the boost - In theory -  

For a Dune car the ideal compression IMO is close to 10:1  at 11lbs boost - the higher compression makes the transition from non boost to boost way smoother - so when you are rolling through the dunes at 2000 Rom and you stomp it - the transition to boost is great - it feels smooth and presses you back and of course skys the car ... going to 9- 8.5:1 is great for drags where you need to pack 40Lbs in cylinders. 

9:5 and 16Lbs boost on e-85 is a dream - you can basically run a lot of timing and make close if not over 1000RWHP, I did a similar engine with LS3 heads and KB 4.7 and it makes 1030 safe HP on e-70 ( its set for flex fuel and his local e-85 station measures out at e-70 most of the time on his Holley dash) if he runs VP's version of e-85 iot makes more HP (2 degrees more timing ) his rev limiter is set at 5900PRM - its super safe.    - BUT on a stock bottom end  ... Crank is fine  - rods and pistons will be at their limit you will need to keep revs under 6K and you will need to swap out the ring pack for steel rings  - their are some tricks your builder should know.  If you can afford it - time to swap pistons and rods  and step up to a 4.5 SC.   That will give you 20Lb capable but you should not go over 16Lbs or the next issue will be head gaskets ... anyway a lot more to it than I can cover, but on e-85  and especially if you check the fuel if its station bought to make sure its e-70 or better - you can have a lot of fun 

By The Way if you go SC at 16lbs of boost your driving style will change pretty fast  - cruising will be at 2K and you will have your hands full when you stab it ... 

 
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Fullthrottleguy said:
the Ls7 if you kept it stock is 11.1 compression  and that sound high - but cam design and incredible quench design of the heads prevent detonation better than any other LS  -  On pump you will Not be able to go over 11Lbs boost - even if you went to 9:1  - you could just run more timing (more power).  But since you are e-85.... e-85 is a wonder drug for Boost - not only is it 110 octane (likely) but its also got incredible cooling  - its more efficient than any heat exchanger and most intercoolers ... so you can crank up the boost - In theory -  

For a Dune car the ideal compression IMO is close to 10:1  at 11lbs boost - the higher compression makes the transition from non boost to boost way smoother - so when you are rolling through the dunes at 2000 Rom and you stomp it - the transition to boost is great - it feels smooth and presses you back and of course skys the car ... going to 9- 8.5:1 is great for drags where you need to pack 40Lbs in cylinders. 

9:5 and 16Lbs boost on e-85 is a dream - you can basically run a lot of timing and make close if not over 1000RWHP, I did a similar engine with LS3 heads and KB 4.7 and it makes 1030 safe HP on e-70 ( its set for flex fuel and his local e-85 station measures out at e-70 most of the time on his Holley dash) if he runs VP's version of e-85 iot makes more HP (2 degrees more timing ) his rev limiter is set at 5900PRM - its super safe.    - BUT on a stock bottom end  ... Crank is fine  - rods and pistons will be at their limit you will need to keep revs under 6K and you will need to swap out the ring pack for steel rings  - their are some tricks your builder should know.  If you can afford it - time to swap pistons and rods  and step up to a 4.5 SC.   That will give you 20Lb capable but you should not go over 16Lbs or the next issue will be head gaskets ... anyway a lot more to it than I can cover, but on e-85  and especially if you check the fuel if its station bought to make sure its e-70 or better - you can have a lot of fun 

By The Way if you go SC at 16lbs of boost your driving style will change pretty fast  - cruising will be at 2K and you will have your hands full when you stab it ... 
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My problem is my engine builder , quoted me 4 weeks to tear apart inspect and rebuild engine with new cam. It took 12 weeks... Then I dropped the engine in the car and bought a Holley terminator from them and paid him to install the terminator and tune the car. he quoted me 2 weeks, it took 6 weeks for me to realize I had to pick up the car figure out the terminator myself and find a different tuner. I am at the point where I need to find a new engine guy or figure it out myself. Just trying to find the best way to get another 200 hp out of this engine.

 
parker@gearone said:
My problem is my engine builder , quoted me 4 weeks to tear apart inspect and rebuild engine with new cam. It took 12 weeks... Then I dropped the engine in the car and bought a Holley terminator from them and paid him to install the terminator and tune the car. he quoted me 2 weeks, it took 6 weeks for me to realize I had to pick up the car figure out the terminator myself and find a different tuner. I am at the point where I need to find a new engine guy or figure it out myself. Just trying to find the best way to get another 200 hp out of this engine.
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I am sure if you ask on GD for engine builders and tuners  in your area you will find some good ones- although finding ones that deliver on time  ...  thats another thing. I have been waiting for 12 weeks for pistons for an engine now.

 
parker@gearone said:
My problem is my engine builder , quoted me 4 weeks to tear apart inspect and rebuild engine with new cam. It took 12 weeks... Then I dropped the engine in the car and bought a Holley terminator from them and paid him to install the terminator and tune the car. he quoted me 2 weeks, it took 6 weeks for me to realize I had to pick up the car figure out the terminator myself and find a different tuner. I am at the point where I need to find a new engine guy or figure it out myself. Just trying to find the best way to get another 200 hp out of this engine.
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Weight  what You just want an extra 200 hp.  Dude slap some Speed stickers and a GD sticker.  And to top it off ad a Mr. Gadget sticker.  BOOM 200hp.   :rofl:

 
ROBERT L said:
Weight  what You just want an extra 200 hp.  Dude slap some Speed stickers and a GD sticker.  And to top it off ad a Mr. Gadget sticker.  BOOM 200hp.   :rofl:
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I was gonna say I know of a few dynos that will get you that ... but they who know .. know

 
Throw a Whipple 3.0 on it. 10lbs of boost. See if you like it or want more. Stock pistons will keep you somewhat sane, power wise until you get bored, then buy an RHS block and build something for the inevitable 4.0 motor... :biggrin:

 
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parker@gearone said:
My problem is my engine builder , quoted me 4 weeks to tear apart inspect and rebuild engine with new cam. It took 12 weeks... Then I dropped the engine in the car and bought a Holley terminator from them and paid him to install the terminator and tune the car. he quoted me 2 weeks, it took 6 weeks for me to realize I had to pick up the car figure out the terminator myself and find a different tuner. I am at the point where I need to find a new engine guy or figure it out myself. Just trying to find the best way to get another 200 hp out of this engine.
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I bought my motor from a dude in the East Valley he's an LS whiz kid. He's very knowledgeable and stuck to his word, held the motor for me without a deposit, and had all the parts I wanted plus some. I'll send you his number. 

 
parker@gearone said:
My problem is my engine builder, quoted me 4 weeks to tear apart inspect and rebuild engine with new cam. It took 12 weeks... Then I dropped the engine in the car and bought a Holley terminator from them and paid him to install the terminator and tune the car. he quoted me 2 weeks, it took 6 weeks for me to realize I had to pick up the car figure out the terminator myself and find a different tuner. I am at the point where I need to find a new engine guy or figure it out myself. Just trying to find the best way to get another 200 hp out of this engine.
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That is easy to get more HP, my naturally Aspirated beats a lot of boosted engines, 

if you want to run E85 you can do natural 13.5-13.8 to one on compression that will get you 100 right there, the LS7 has a very weak sleave, we will not boost them for a off-road vehicle without a Darton Sleeve upgrade $2000,  

To make 800 Crank HP Naturally Aspirated is expensive but doable, still cheaper than boosted, 

  • Frankenstein Alper Series Heads, 
  • .015-.030 Lash lifters  
  • Adjustable Rockers 
  • Alper Grind by Cam-Motion 
  • 4.100 Crank to make it a 440

10.5-10.8 can run 91 makes good HP, 

Boosted will have to fight some issues, i dont care if you have the best air cooling bla bla bla, will always fight air temps on long dune runs, the boosted guys never make it to the end of the run in Idaho without stopping 

Turbos more money than a SC to do it right, 

Whipple makes killer torque, but always will chuck a belt from time to time, and really makes some air temp,  

E85 will save from detonation, but when the air temps get hot, the power you loose from hot air temps will feel like a naturally aspirated motor, 

At the end of the day boosted motors will make killer power, but you cant be cheap about it,  just like comparing a empi 930 cv to Gear one CV, they both work, its how it works over time, 

For what you have now, to do a boosted correctly, from start to finish, from coolers to fuel pumps and all plumbing, it will be around $12,000-15,000 

 
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