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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
Id like to see what u get from both dynos...Im planning similar upgrades...and spray meth...I hope you get 700....but 660 and up would be nice...140+mph 1/4 mile......do dyno with good tires like hoosier or mickeys ...you have light wheels and tires? Some tires are 26lbs hoosiers 315 and others 39lbs..some rims are 19ibs c5z06 fronts and other 31lbs..changing front rotors used for 450 dollars will shed 20lbs off the front ..Back to rear tires ....so if you are running a 140lb rear tires that dont grip dyno instead of an 84ib rear tire setup that does grip ...60lbs of unsprung rotation weight eats horse power change it maybe.Just trying to help...gl
The walbro 450 is almost a complete drop in. I should have taken pictures and written a DIY.
One modification needed is to cut the connector off the 450, leaving as much of the two wires left as you can. You will need to solder the old harness onto the 450, so that your 450 will "plug in" to the Corvette fuel pump module.
The module comes out of the tank as one long cylinder. The top of the cyl holds the fuel filter, FPR, and the float assembly. The bottom half is the fuel pump/bucket.
From a workbench: You need to separate the two halves by gently prying the two apart with a small flathead screwdriver. Once apart, you will see the two halves are still connected by the fuel hose and the electrical harness. The factory fuel hose will not be reused and can be cut off. It will not come off by tugging on it. Using a razor, cut a vertical slit in the factory hose about 2" long down the nipple at the bottom of the fuel filter. You can then use a small screwdriver to gently pry the hose away from the nipple.
Your new fuel pump requires the purchase of SUBMERSIBLE fuel hose. This 3/8" submersible fuel hose is relatively expensive, the short length I bought (can't remember if it was 12" or 18", think it was 12") was like $35 from O'Reilly's auto parts. I don't have a part number, just make sure you get submersible 3/8". Regular fuel hose will disintegrate within 24 hours and you'll be dropping your fuel tank to replace it, which would suck.
If you are careful you can transfer the old fuel pump sock to the walbro. Be very careful, take your time. I did mine successfully. If you reuse the factory sock, zero modification are needed for your factory bucket. The only "mod" is the soldering on the harness, and the aftermarket submersible fuel hose with small worm clamps. That's it.
There is no hard starting with the new pump. At all. That sounds like snake oil from people who aren't familiar with the mod. The factory fuel line maintains over 40 psi overnight so fuel is always right there when you hit the key. Mine lights same as stock.
My 450 has been absolutely reliable for 10k miles.
Here is a related thread that might give some detail. The author did some fuel bucket mods that are unnecessary if the factory inlet sock is retained, but the pictures are great.
The walbro 450 is almost a complete drop in. I should have taken pictures and written a DIY.
One modification needed is to cut the connector off the 450, leaving as much of the two wires left as you can. You will need to solder the old harness onto the 450, so that your 450 will "plug in" to the Corvette fuel pump module.
The module comes out of the tank as one long cylinder. The top of the cyl holds the fuel filter, FPR, and the float assembly. The bottom half is the fuel pump/bucket.
From a workbench: You need to separate the two halves by gently prying the two apart with a small flathead screwdriver. Once apart, you will see the two halves are still connected by the fuel hose and the electrical harness. The factory fuel hose will not be reused and can be cut off. It will not come off by tugging on it. Using a razor, cut a vertical slit in the factory hose about 2" long down the nipple at the bottom of the fuel filter. You can then use a small screwdriver to gently pry the hose away from the nipple.
Your new fuel pump requires the purchase of SUBMERSIBLE fuel hose. This 3/8" submersible fuel hose is relatively expensive, the short length I bought (can't remember if it was 12" or 18", think it was 12") was like $35 from O'Reilly's auto parts. I don't have a part number, just make sure you get submersible 3/8". Regular fuel hose will disintegrate within 24 hours and you'll be dropping your fuel tank to replace it, which would suck.
If you are careful you can transfer the old fuel pump sock to the walbro. Be very careful, take your time. I did mine successfully. If you reuse the factory sock, zero modification are needed for your factory bucket. The only "mod" is the soldering on the harness, and the aftermarket submersible fuel hose with small worm clamps. That's it.
There is no hard starting with the new pump. At all. That sounds like snake oil from people who aren't familiar with the mod. The factory fuel line maintains over 40 psi overnight so fuel is always right there when you hit the key. Mine lights same as stock.
My 450 has been absolutely reliable for 10k miles.
Here is a related thread that might give some detail. The author did some fuel bucket mods that are unnecessary if the factory inlet sock is retained, but the pictures are great.
Any reason for not bumping up to 13.8 or so SCR? What DCR will 13:1 net you?
Mostly finances in terms of keeping the stock bottom end. 13.8 would have been easy with aftermarket pistons, but there just were not any reputable machine shops local to me that could have done the machine work and balancing. And I really didn't want to send the block off for that work...and if I sent my block off...might as well just send it to ERL for it to be resleeved and go to a 440. So for me, I was looking for local machining or I would just keep it SBE. I would be OK with angle milling and higher SCR on E85. I just don't know if angle milling is something that Tony provides, I haven't asked him. It's an interesting thought though. I'm planning MS109 for an upcoming event, I'm not sure how MS109 compares to E85, very curious actually.
Josh, I don't put too much stock in DCR regardless of how it is computed. Cylinder pressure is what will determine sensitivity to detonation and cylinder pressure will vary by RPM. It would take some pretty sophisticated software to accurately model the cylinder pressure of engines of various displacements, STR, valve timings, and fuel types. The simple DCR calculators found online have no such capability and in my opinion are virtually useless. The OEMs have huge capability in this area of computational modeling. When modifying our cars, this is one area where the aftermarket is largely left to trial and error. Not that trial and error isn't OK, but we must rely heavily on the collective experience of the racing and engine building community and therefore I think it's best to stick with those vendors with the best track record of success and greatest R&D capability.
Here is a link with some instructive plots of RPM vs cylinder pressure. This is a comparison a of gasoline to CNG. It would be cool if we could find a comparison to 93 octane vs E85. Other good graphs here include a look at heat release rates and efficiency metrics. https://www.researchgate.net/figure/...soline-and-CNG
Thank you for the great information Scott. I agree that DCR is difficult to analyze, let alone compare.
A big reason as to why I decided to go with Mamo Motorsports was Tony's expertise in engine dynamics and design. There really hasn't been an aspect of this build that wasn't collaborated with Tony.
An excerpt from Steve at RED regarding high compression, cracking sleeves, octane, and detonation.
"Stock LS7 blocks hold up fine with race gas. You must keep the stock block out of detonation or you will split a wall.
It is a lot easier for me and cheaper for you to sleeve the block before it cracks if you intend to run pump gas with high compression, boost or nitrous."
An excerpt from Steve at RED regarding high compression, cracking sleeves, octane, and detonation.
"Stock LS7 blocks hold up fine with race gas. You must keep the stock block out of detonation or you will split a wall.
It is a lot easier for me and cheaper for you to sleeve the block before it cracks if you intend to run pump gas with high compression, boost or nitrous."
I wish he could provide some updated feedback. I'm debating 13.8:1 but I have a forged bottom end on stock sleeves. I'd also like to slam it with a 200-225 shot on top of that. I know the sleeves are the weak link but it's tempting.
I know of several LS7s in the 12.0-12.4:1 SCR range but the DCR is 8.3-8.8. I'm currently at 11.5:1 and 8.9:1, respectively. They've all been ran hard for the past several years with no known issues.
I can only imagine the torque curve of a 13.0+ compression LS7 on the gun.
Still on the east coast visiting family but wanted to chime in quickly. After the additional cut on the deck (another .012 or so), we will have a 60 cc chamber and a true static CR of 12.75 to 1 taking into account head gasket volume etc. While this is certainly a stout number its not much higher than a handful of other shops E85 builds and less than others even more aggressive.
It is the limit of what I am comfy with using stock pistons etc and any more than this could also create fitment issues with the manifold plus excessive milling of the heads starts to effect airflow (CFM) in a negative fashion as well.
12.5 - 12.75 on a stock block (IMO) is about all you would want to push the CR to in a more aggressive race gas or E85 style build. Needing more than that is better achieved with domed aftermarket pistons and less milling of the heads.
Typing all this from a phone so excuse the right down to business approach of this post....LOL
Josh has been great to work with and Im very much looking forward to the outcome of this build!!
Thank you for the great information Scott. I agree that DCR is difficult to analyze, let alone compare.
A big reason as to why I decided to go with Mamo Motorsports was Tony's expertise in engine dynamics and design. There really hasn't been an aspect of this build that wasn't collaborated with Tony.
No problem Josh! It gave me a break from decorating the Christmas Tree! For me, its Mamo Motorsports and Katech! Best in airflow and durability.
Originally Posted by Josh B.
An excerpt from Steve at RED regarding high compression, cracking sleeves, octane, and detonation.
"Stock LS7 blocks hold up fine with race gas. You must keep the stock block out of detonation or you will split a wall.
It is a lot easier for me and cheaper for you to sleeve the block before it cracks if you intend to run pump gas with high compression, boost or nitrous."
Steve is very accessible and generous with information, and he has been doing sleeves for race engines for a long time. That link I posted is from 2009, and today I think the "science is settled" (at the warmers would say!) on durability of LS7 sleeves.
Going to E85, and getting the valve events right and most significantly the tune will be key to the stock block surviving. In the long run, I can see you ending up with that 440/sleeved block. These builds are too expensive to run the risk of breaking a piston or sleeve for very long. A good E85 build incorporates several of the ideas used in the Mazda Skyactive engine technologies.
1. Higher mechanical compression for increased power and efficiency. (Skyactive = 13.1 for U.S. market and 87 octane fuel, and 14.1 for other markets and higher octane fuels.)
2. Lower cylinder charge temperature via better exhaust scavenging (and lower intake overlap in the case of Skyactive). E85 also helps to lower charge temp due to the 85% ethanol content. Skyactive engines actually use a long tube merge type header to improve exhaust scavenging to help lower cylinder temps.
3. Intensifying airflow for more efficient cylinder filling. Tony's ported MSD and efficient 265cc intake ports will work in the same way.
Skyactive also incorporates a number of friction reduction technologies, many of which can be applied to the LS7. Cylinder roundness, and the seal and efficiency of the ring pack can have a significant influence on power and efficiency. The Gen V LT1 and LT4 engines use the new Mahle HV385 1mm, 1mm, 2mm ring package which provide better gas sealing and less friction than Gen IV LS rings. As Steve noted in that LS1tech post, "Wet MID liner is a bit more but will take a lot more abuse and the cylinders will stay rounder than any dry liner block, factory, resleeved, or after market". This along with the right rings will reduce blow-by and decrease the amount of oil getting sucked into the intake or catch can.
I recently picked up an LS7 short block with a crack in the #7 cylinder sleeve due to detonation. It's hard to find these at a decent price, but patience will eventually reward. I'm sending the block to Steve for the Darton MID "wet" sleeves. The following is from a communication with Steve a few months ago. I was gathering information on sleeving versus using an RHS block for a road course engine <650 crank HP and NA. " There is no advantage to the RHS block at that power level. There is a disadvantage in price and weight. I am a WD for Dart which will go out to 4.185" bore. Waste of money for what you are doing. " I'm still on the fence between going 440 in. or staying with 427 in. The 4.125 bore would lower the cost for the pistons and rings as I can use Mahle forgings with the rings I wan't and retain the LS7 Ti rods and forged crank. I need to figure out if 440 in. will need bigger ports vs. 427. I'm watching your build very closely!
I have been really interested in the SkyActive approach to engine efficiency. Mazda is headed in the right direction. Did I read correctly that Steve charges less than ERL for a resleeve (4.185)? ERL sounds nice with their ductile iron dry liner. They wanted to install 1/2" head studs for an extra $600, seemed like an upcharge if you ask me, but that's just my .02. Is more head retention bad? No. Required at 700hp? Maybe...maybe not.
I have been really interested in the SkyActive approach to engine efficiency. Mazda is headed in the right direction. Did I read correctly that Steve charges less than ERL for a resleeve (4.185)? ERL sounds nice with their ductile iron dry liner. They wanted to install 1/2" head studs for an extra $600, seemed like an upcharge if you ask me, but that's just my .02. Is more head retention bad? No. Required at 700hp? Maybe...maybe not.
I'm pretty sure that was a comparison of ERL's "Super Deck" to RED doing dry sleeves. Super Deck is similar to RED's Darton MID sleeves, a full ductile iron water cooled sleeve that eliminates the aluminum cylinder component entirely. Both RED and ERL offer dry and wet sleeves for similar cost. I don't think you need to go with larger head studs if you are staying NA. All that stuff is aimed at 1000+HP boost/nitrous engines. If I needed that much HP, I would just go with an LSX iron block or Dart block.
Id like to see what u get from both dynos...Im planning similar upgrades...and spray meth...I hope you get 700....but 660 and up would be nice...140+mph 1/4 mile......do dyno with good tires like hoosier or mickeys ...you have light wheels and tires? Some tires are 26lbs hoosiers 315 and others 39lbs..some rims are 19ibs c5z06 fronts and other 31lbs..changing front rotors used for 450 dollars will shed 20lbs off the front ..Back to rear tires ....so if you are running a 140lb rear tires that dont grip dyno instead of an 84ib rear tire setup that does grip ...60lbs of unsprung rotation weight eats horse power change it maybe.Just trying to help...gl
Thanks for your advice regarding wheel/tire combo for use on the dyno. I just bought some 17" rear Weld RT-S wheels with M&H drag radials. The tires are about 2lb's lighter per tire compared to MPSS 345s (my street tires) but the wheels are significantly lighter at 22lbs versus the 26lbs of the stock 19x12. 6lbs lighter per wheel/tire, 12lbs less total rotating mass. Might free up a pony or two, but then, drag radials have more rolling resistance, so who the hell knows. Great stuff to think about.
"660-700rwhp" would be a really awesome reward for Tony's hard work and my wrench turning. A fellow forum member hit 642rwhp with a hyd roller cam of similar dimensions. I think I will be close. This build has a crank scraper, a vacuum pump, and maybe some more compression, so we will see where the chips fall. I'm also hopeful that the LG ram air intake will improve 1/2 mile MPH, LG claimed that his race car would pick up 2 mph on a long straight away with his intake. If I had unlimited access to a tuner who would calibrate my MAF curve I would be willing to do back to back testing to validate the LG gains, if any. Tested against a traditional Halltech.
It seems like this combo has made, in theory, small improvements all around the engine. Not one big one like a power adder, so I am REALLY looking forward to seeing how it all comes together. Anyone who has spoken to Tony Mamo about cylinder heads or engines knows that he is all about offering products in a total package that all come together to work in harmony, greater than the sum of the parts.
I'm also considering some "race mufflers" just for the 1/2 mile competition, basically just some 3" bullets after the X-pipe with turn downs. Depending if I have the time. I might be busy working on a customer's Z06 mufflers with my true 3" Muffler Mod. The Bullets might be worth a few hp, ungodly loud, but on a closed runway....who the heck cares
I'm also considering some "race mufflers" just for the 1/2 mile competition, basically just some 3" bullets after the X-pipe with turn downs. Depending if I have the time. I might be busy working on a customer's Z06 mufflers with my true 3" Muffler Mod. The Bullets might be worth a few hp, ungodly loud, but on a closed runway....who the heck cares
Or those tiny Burns mufflers straight off the collectors!
If I had unlimited access to a tuner who would calibrate my MAF curve I would be willing to do back to back testing to validate the LG gains, if any. Tested against a traditional Halltech.
If I lived closer I'd do it for you. It is two tokens for HPTuners which I'd split the cost with you just to find out. $50 each. I'll be at the 1/2 mile logging my runs with my modified Halltech. Could easily do it there but that's race day and I'm sure you don't want to make changes on race day. I'll throw the offer out there for you though.
Thanks for your advice regarding wheel/tire combo for use on the dyno. I just bought some 17" rear Weld RT-S wheels with M&H drag radials. The tires are about 2lb's lighter per tire compared to MPSS 345s (my street tires) but the wheels are significantly lighter at 22lbs versus the 26lbs of the stock 19x12. 6lbs lighter per wheel/tire, 12lbs less total rotating mass. Might free up a pony or two, but then, drag radials have more rolling resistance, so who the hell knows. Great stuff to think about.
"660-700rwhp" would be a really awesome reward for Tony's hard work and my wrench turning. A fellow forum member hit 642rwhp with a hyd roller cam of similar dimensions. I think I will be close. This build has a crank scraper, a vacuum pump, and maybe some more compression, so we will see where the chips fall. I'm also hopeful that the LG ram air intake will improve 1/2 mile MPH, LG claimed that his race car would pick up 2 mph on a long straight away with his intake. If I had unlimited access to a tuner who would calibrate my MAF curve I would be willing to do back to back testing to validate the LG gains, if any. Tested against a traditional Halltech.
It seems like this combo has made, in theory, small improvements all around the engine. Not one big one like a power adder, so I am REALLY looking forward to seeing how it all comes together. Anyone who has spoken to Tony Mamo about cylinder heads or engines knows that he is all about offering products in a total package that all come together to work in harmony, greater than the sum of the parts.
I'm also considering some "race mufflers" just for the 1/2 mile competition, basically just some 3" bullets after the X-pipe with turn downs. Depending if I have the time. I might be busy working on a customer's Z06 mufflers with my true 3" Muffler Mod. The Bullets might be worth a few hp, ungodly loud, but on a closed runway....who the heck cares
I have the perfect catback for you if you're interested. I'll be posting it up for sale soon. It's B&B bullets that were professionally modified to have turndowns. When I say professional I mean they are so nice I was convinced they came from B&B with the turndowns. So convinced I even called them asking what I had. Turns out they knew the exact ones I had and who modified them. With the tips bullets shed 22lbs so I suspect these are around a 26-30lb savings. They did seem to help me at the track a touch as I got a new PB after installing them.
If I lived closer I'd do it for you. It is two tokens for HPTuners which I'd split the cost with you just to find out. $50 each. I'll be at the 1/2 mile logging my runs with my modified Halltech. Could easily do it there but that's race day and I'm sure you don't want to make changes on race day. I'll throw the offer out there for you though.
What did u modifiy on the halltech? I have a Halltech and I'm convinced it's holding me back due to the amount of vacuum I'm seeing at WOT and not being able to keep the IATs down enough.
This LG intake on paper seems to be the ticket, but dang it's expensive. I think there is a huge need for a new intake for our cars. Something like the LG but cheaper. All that carbon isn't needed and likely adds a lot of cost. I've been very tempted to design something new. Just hard to pay for any tooling with such small volumes, so it really limits the design possibilities....
11-26-2016, 06:19 PM
