Slp Zl-402 ?
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is that a good shortblock to buy ? the HC ZL402 IS IT WORTH THE $$$$ REASONMN I ASK IS CAUSE IM IN THE MARKET FOR A NEW SHORTBLOCK AND IT SEAMS LIKE A PREATY GOOD DEAL BUT IVE HEARD SOME BAD THINGS FRROM THOUGHS S/B ?
ANY HELP OR IDEAS ?
ANY HELP OR IDEAS ?
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I've got an SLP 402 with AFR 225 heads,Eagle crank and Manley forged pistons and rods. 11:1 compression, all factory intake system, 228/230 Comp cam with .595" lift, LG LongTube headers and factory TI mufflers. 481rwhp and 489rwt.
The engine now has about 3500 miles on it and was carefully broken in. I am not a neophyte when it comes to performance motors or cars. I have built several cars from the ground up and assembled more than a few motors making roughly the same power as this SLP402.
My hp numbers are good, even my highway mileage at 75mph is 26-28mpg.
BUT... I do not like the apparent piston slap and I really don't like going through a quart of 10-30 M1 every 750 miles!! The cars sounds like a bloody diesel EVEN AFTER IT IS WARMED UP. When accelerating up a hill in 6th it really sounds like a diesel. This is not detonation. I have HP Tuner, no knock recorded whatsoever. I can increase the timing and induce minor knock above 23-24 degrees advance WOT so I know it is not a faulty knock sensor.
I am inclined to agree that the 4" stroke really exposes a lot of piston skirt which makes sense that this would aggravate piston slap. A factory LS7 short block is sure tempting. I would probably seriously consider this if changing out these engines wasn't such a PITA. A good friend of mine has a '07 ZO6. His 4" stroke forged engine is smooth as silk. I am royally bummed that mine is not. For the $$ I should've just bought a new Z, but because a valve spring broke at 78,000 miles and toasted my engine my options were somewhat limited. I thought building a C6ZO6 equivalent with my C5Z made sense. My car still looks like the day I drove it off the showroom floor. I love the power, but it burns oil like and old farm truck and doesn't sound much better except at WOT (which is nothing short of fabulous!)
Would going to 50wt oil help? Living in San Jose, CA I don't have sub zero startup concerns. I know not to push a cold engine and know that doing so with heavy oil can blow a filter right off the block. I always used 50 wt Valvoline in my 69 L88. By the way, the factory 427 L88 made virtually the same rwhp and used a lot less oil even with its forged pistons.
Chuck
The engine now has about 3500 miles on it and was carefully broken in. I am not a neophyte when it comes to performance motors or cars. I have built several cars from the ground up and assembled more than a few motors making roughly the same power as this SLP402.
My hp numbers are good, even my highway mileage at 75mph is 26-28mpg.
BUT... I do not like the apparent piston slap and I really don't like going through a quart of 10-30 M1 every 750 miles!! The cars sounds like a bloody diesel EVEN AFTER IT IS WARMED UP. When accelerating up a hill in 6th it really sounds like a diesel. This is not detonation. I have HP Tuner, no knock recorded whatsoever. I can increase the timing and induce minor knock above 23-24 degrees advance WOT so I know it is not a faulty knock sensor.
I am inclined to agree that the 4" stroke really exposes a lot of piston skirt which makes sense that this would aggravate piston slap. A factory LS7 short block is sure tempting. I would probably seriously consider this if changing out these engines wasn't such a PITA. A good friend of mine has a '07 ZO6. His 4" stroke forged engine is smooth as silk. I am royally bummed that mine is not. For the $$ I should've just bought a new Z, but because a valve spring broke at 78,000 miles and toasted my engine my options were somewhat limited. I thought building a C6ZO6 equivalent with my C5Z made sense. My car still looks like the day I drove it off the showroom floor. I love the power, but it burns oil like and old farm truck and doesn't sound much better except at WOT (which is nothing short of fabulous!)
Would going to 50wt oil help? Living in San Jose, CA I don't have sub zero startup concerns. I know not to push a cold engine and know that doing so with heavy oil can blow a filter right off the block. I always used 50 wt Valvoline in my 69 L88. By the way, the factory 427 L88 made virtually the same rwhp and used a lot less oil even with its forged pistons.
Chuck
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Originally Posted by dame
stay away from slp....you get what you pay for remember that
Please let me know why you feel that customers should stay away from SLP ZL402.
Thanks
Hank
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Originally Posted by SLPPower
Dame,
Please let me know why you feel that customers should stay away from SLP ZL402.
Thanks
Hank
Please let me know why you feel that customers should stay away from SLP ZL402.
Thanks
Hank
What you are paying for are ALL high quality, ALL made in the USA parts assembled to OE tolerances.
If you have not seen any of my posts please read below on my introduction posted in Nov.:
My name is Hank Daniecki and I am the new Director of Engineering at SLP Performance Parts. I am intimately familiar with ALL SLP parts as I have worked for SLP as an engineer for the last 6 years. SLP's engineering department will be taking a much more active role on LS1Tech and many other boards on the web to help clear up any issues or problems that anyone might have with any and all SLP products. There are many rumors and false claims being made that we want to clear up as soon as they are spotted on LS1 tech. The SLP Engineering Department loves input from customers and the challenge to make our customers as happy as humanly possible. We take our jobs very seriously. We do not like to see members bash our products that we spend long days and nights designing without solid ground to stand on. The SLP Engineering Department and I welcome with open arms constructive criticism and factual replies. I will make sure all questions are answered with great detail. Any and all on the board, please do not hesitate to email me with any issues or problems you might have. Please include in your email a phone number so that we can communicate by phone if needed. I look forward to getting SLP a better reputation on this board. Our products are top notch and we take the greatest pride in the work that we do. Please take the time to check out our website and our new 100pg catalog; I am sure you will agree our products are top notch. Also, we have re-opened the SLP Installation and Dyno Center. Please find the link below.
http://www.slponline.com/20061006_install_dyno.asp
Thank You.
Hank
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SLP Performance Parts
www.SLPonline.com
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what ever happened to that guy that had the motor frag apart, the one that blew up while teh guy was in a parking lot... never did hear the results of the findings on that one... coming clean with stuff like that, would go miles for bettering the reputation of the motors.
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Originally Posted by SLPPower
Dame,
What you are paying for are ALL high quality, ALL made in the USA parts assembled to OE tolerances.
If you have not seen any of my posts please read below on my introduction posted in Nov.:
My name is Hank Daniecki and I am the new Director of Engineering at SLP Performance Parts. I am intimately familiar with ALL SLP parts as I have worked for SLP as an engineer for the last 6 years. SLP's engineering department will be taking a much more active role on LS1Tech and many other boards on the web to help clear up any issues or problems that anyone might have with any and all SLP products. There are many rumors and false claims being made that we want to clear up as soon as they are spotted on LS1 tech. The SLP Engineering Department loves input from customers and the challenge to make our customers as happy as humanly possible. We take our jobs very seriously. We do not like to see members bash our products that we spend long days and nights designing without solid ground to stand on. The SLP Engineering Department and I welcome with open arms constructive criticism and factual replies. I will make sure all questions are answered with great detail. Any and all on the board, please do not hesitate to email me with any issues or problems you might have. Please include in your email a phone number so that we can communicate by phone if needed. I look forward to getting SLP a better reputation on this board. Our products are top notch and we take the greatest pride in the work that we do. Please take the time to check out our website and our new 100pg catalog; I am sure you will agree our products are top notch. Also, we have re-opened the SLP Installation and Dyno Center. Please find the link below.
http://www.slponline.com/20061006_install_dyno.asp
Thank You.
Hank
__________________
Hank Daniecki
Director of Engineering
SLP Performance Parts
www.SLPonline.com
What you are paying for are ALL high quality, ALL made in the USA parts assembled to OE tolerances.
If you have not seen any of my posts please read below on my introduction posted in Nov.:
My name is Hank Daniecki and I am the new Director of Engineering at SLP Performance Parts. I am intimately familiar with ALL SLP parts as I have worked for SLP as an engineer for the last 6 years. SLP's engineering department will be taking a much more active role on LS1Tech and many other boards on the web to help clear up any issues or problems that anyone might have with any and all SLP products. There are many rumors and false claims being made that we want to clear up as soon as they are spotted on LS1 tech. The SLP Engineering Department loves input from customers and the challenge to make our customers as happy as humanly possible. We take our jobs very seriously. We do not like to see members bash our products that we spend long days and nights designing without solid ground to stand on. The SLP Engineering Department and I welcome with open arms constructive criticism and factual replies. I will make sure all questions are answered with great detail. Any and all on the board, please do not hesitate to email me with any issues or problems you might have. Please include in your email a phone number so that we can communicate by phone if needed. I look forward to getting SLP a better reputation on this board. Our products are top notch and we take the greatest pride in the work that we do. Please take the time to check out our website and our new 100pg catalog; I am sure you will agree our products are top notch. Also, we have re-opened the SLP Installation and Dyno Center. Please find the link below.
http://www.slponline.com/20061006_install_dyno.asp
Thank You.
Hank
__________________
Hank Daniecki
Director of Engineering
SLP Performance Parts
www.SLPonline.com
Hank,
Do you have any response or input about Chuck's post???
Originally Posted by Chuck Harmon
... I've got an SLP 402 .... I do not like the apparent piston slap and I really don't like going through a quart of 10-30 M1 every 750 miles!! The cars sounds like a bloody diesel EVEN AFTER IT IS WARMED UP. When accelerating up a hill in 6th it really sounds like a diesel. ...
Chuck
Chuck
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Originally Posted by JL ws-6
what ever happened to that guy that had the motor frag apart, the one that blew up while teh guy was in a parking lot... never did hear the results of the findings on that one... coming clean with stuff like that, would go miles for bettering the reputation of the motors.
JL ws-6,
It is not a matter of coming clean, because I wish that I could tell you ALL of the details and results. But, SLP and the customer came to a legal agreement that the results of the testing would not be published. I can tell you that the customer was completely satisfied with the outcome.
If this one incident is keeping people from purchasing a ZL402, that is a shame, because there are dozens of others that are very successful with these motors and a handful that are making 800+ with not an issue.
Thanks
Hank
Last edited by SLPPower; 12-22-2006 at 12:22 PM.
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Originally Posted by SideStep
Hank,
Do you have any response or input about Chuck's post???
![Lurk](https://ls1tech.com/forums/images/smilies3/lurk.gif)
Do you have any response or input about Chuck's post???
![Lurk](https://ls1tech.com/forums/images/smilies3/lurk.gif)
I am sure we could have a month long conversation about whether forged pistons make more noise then the stock LS1 pistons and everyone’s viewpoint and opinions. As well as the proper break in procedure. I do not want this to go in that direction.
My response to Chuck's post is:
750miles per quart is on the high side. There are numerous reasons for burning oil and it would become a very non-productive post to start questioning all the reasons. As for the piston slap; I would like to hear the motor. I am sure, Chuck you are reading this post. If you ever are in the NJ area, I will be more then willing to discuss and listen to the motor in person. As well, all of our blocks are serial # on the driver’s side rear deck surface with a ZL####, if you could get me that number I can give you the build sheet on that particular motor. All motors built by SLP have there own unique build sheet. This will have to wait though until Jan 2nd as SLP will be closed for the holidays starting today. And I am not in the shop, waiting for a plane actually. The fact that the car is getting great gas mileage and making good power leads me to believe that the piston slap is mild.
Thanks
Hank
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The above posts and the correseponding, ahem, responses are the reasons why vendors should refrain from ever posting on forums. It will almost never work to your advantage, no matter HOW right you think you are. Focus your efforts on making your customers happy, and let them be your voice. The downside is that people are generally quicker to post bad experiences than good, but that's life.
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Originally Posted by SLPPower
JL ws-6,
It is not a matter of coming clean, because I wish that I could tell you ALL of the details and results. But, SLP and the customer came to a legal agreement that the results of the testing would not be published. I can tell you that the customer was completely satisfied with the outcome.
If this one incident is keeping people from purchasing a ZL402, that is a shame, because there are dozens of others that are very successful with these motors and a handful that are making 800+ with not an issue.
Thanks
Hank
It is not a matter of coming clean, because I wish that I could tell you ALL of the details and results. But, SLP and the customer came to a legal agreement that the results of the testing would not be published. I can tell you that the customer was completely satisfied with the outcome.
If this one incident is keeping people from purchasing a ZL402, that is a shame, because there are dozens of others that are very successful with these motors and a handful that are making 800+ with not an issue.
Thanks
Hank
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Originally Posted by SLPPower
JL ws-6,
It is not a matter of coming clean, because I wish that I could tell you ALL of the details and results. But, SLP and the customer came to a legal agreement that the results of the testing would not be published. I can tell you that the customer was completely satisfied with the outcome.
If this one incident is keeping people from purchasing a ZL402, that is a shame, because there are dozens of others that are very successful with these motors and a handful that are making 800+ with not an issue.
Thanks
Hank
It is not a matter of coming clean, because I wish that I could tell you ALL of the details and results. But, SLP and the customer came to a legal agreement that the results of the testing would not be published. I can tell you that the customer was completely satisfied with the outcome.
If this one incident is keeping people from purchasing a ZL402, that is a shame, because there are dozens of others that are very successful with these motors and a handful that are making 800+ with not an issue.
Thanks
Hank
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Hank,
Thanks for your response. I look forward to speaking with you soon. I am hoping I can get you that engine number, but it is in a really tough place to see. There have been very numerous posts about SLP that I have read over the last year, including the one where an engine grenaded with 4 or 5 bad pistons. Speaking for myself, the consumer's story blaming SLP still doesn't convince me.
When you consider that the engine starts with a brand new LS2 block, not a used one; and is fitted with either Eagle or Callies cranks, Manley forged rods and pistons, this is a premium assembly. I prefer to give SLP the benefit of the doubt in working this out. The fact that their guy, Hank, would respond from an airport (hopefully not Denver) speaks volumes to me regarding customer care.
To All, have a wonderful Christmas!
Chuck
Thanks for your response. I look forward to speaking with you soon. I am hoping I can get you that engine number, but it is in a really tough place to see. There have been very numerous posts about SLP that I have read over the last year, including the one where an engine grenaded with 4 or 5 bad pistons. Speaking for myself, the consumer's story blaming SLP still doesn't convince me.
When you consider that the engine starts with a brand new LS2 block, not a used one; and is fitted with either Eagle or Callies cranks, Manley forged rods and pistons, this is a premium assembly. I prefer to give SLP the benefit of the doubt in working this out. The fact that their guy, Hank, would respond from an airport (hopefully not Denver) speaks volumes to me regarding customer care.
To All, have a wonderful Christmas!
Chuck
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I have a new ZL402 sitting in my garage. I like the look of it so far. Callies crank, manley rods & pistons, and a new block.
I'll be installing it in the next few weeks.
BTW, my sales guy (Joey) was very helpful. The only negative was they don't take credit cards, so I lost a bunch of US Air miles on the deal!
Bob K. (RGKSR)
I'll be installing it in the next few weeks.
BTW, my sales guy (Joey) was very helpful. The only negative was they don't take credit cards, so I lost a bunch of US Air miles on the deal!
Bob K. (RGKSR)
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Originally Posted by JL ws-6
I can personally think of 5 people that ended up going a differnet route because that whole situation scared them. if you've gotten the situation resolved, good for you and the customer, I just hope that the reason behind it was a one time deal, for your sake and all the other people that have/will buy one of those shortblocks that's all.
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Originally Posted by 429 Mustang
The above posts and the correseponding, ahem, responses are the reasons why vendors should refrain from ever posting on forums. It will almost never work to your advantage, no matter HOW right you think you are. Focus your efforts on making your customers happy, and let them be your voice. The downside is that people are generally quicker to post bad experiences than good, but that's life.
Since the inception of the internet it is important that companies communicate to their customers and potential customers using these forums as it is their cyber voice that needs to be heard in order to be successful in this age. It is a very effective way to serve customers as well as market products. Staying silent and not helping customers on this forum is why SLP has taken such a beating as of late on this site. My staff and I are hear to change that. Obviously not all responses and posts will be positive, this is understood and I believe that most know why, as you stated; people are quicker to post bad experiences then good, but as you can read above, my responding to this post will get Chuck the customer service he deserves and needs. SLP as a vender posting will at the very least get Chuck and I together to discuss possible reasons for the excessive oil usage. At best we will resolve the issue and Chuck can be more comfortable in his vehicle.
Thank you for your opinion but SLP will continue to post with the best intentions, providing accurate information while helping our customers with any issues they may have.
Thank goodness not in Denver. Now in a much warmer climate.
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Thanks
Hank