Put Ls7 Engine or Stroke My ls3?
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Instructor
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Put Ls7 Engine or Stroke My ls3?
Hey..
I have a C6 AT '08. It has a Haltech CAI and Kooks L. Headrs no cats and corsa extreme catback. Ran around 50k miles and dynoed with this set up 420 rwhp.
Not a daily driver but once or twice a week for fun. I go for drag like once every two months and thats why mainly I want to do the work (occasionally on street
.
My aim is to go now NA targeting 600 rwhp and around 10.5 seconds on quarter mile.
What do you recommed?
1.
Stroke my ls3 engine 416 ci with cam kit (valve springs etc)
port the heads
fast 102 and throtle
or
2.
put an ls7 (will buy from a friend that has forged pistons and coated bearings but still 427 ci).
cam package
port the ls3 heads
fast 102 and throtle
do the wet sump conversions.(not sure if it fits well though)
Which of those will be closer to my target and more reliable?
I have a C6 AT '08. It has a Haltech CAI and Kooks L. Headrs no cats and corsa extreme catback. Ran around 50k miles and dynoed with this set up 420 rwhp.
Not a daily driver but once or twice a week for fun. I go for drag like once every two months and thats why mainly I want to do the work (occasionally on street
. My aim is to go now NA targeting 600 rwhp and around 10.5 seconds on quarter mile.
What do you recommed?
1.
Stroke my ls3 engine 416 ci with cam kit (valve springs etc)
port the heads
fast 102 and throtle
or
2.
put an ls7 (will buy from a friend that has forged pistons and coated bearings but still 427 ci).
cam package
port the ls3 heads
fast 102 and throtle
do the wet sump conversions.(not sure if it fits well though)
Which of those will be closer to my target and more reliable?
Last edited by VetteArts; Feb 7, 2015 at 03:23 PM.
Safety Car
Joined: Jul 2009
Posts: 3,755
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From: Baton Rouge LA
St. Jude Donor '14, '16
You'd also need ls7 heads in your second scenario.
I'm thinking of doing a 416 myself because it is cheaper than an ls7 swap, not to mention the added trouble that the dry sump swap would add (unless the ls7 is already setup for wet sump).
I'm thinking of doing a 416 myself because it is cheaper than an ls7 swap, not to mention the added trouble that the dry sump swap would add (unless the ls7 is already setup for wet sump).
Thread Starter
Instructor
Joined: Feb 2015
Posts: 143
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Thread Starter
Instructor
Joined: Feb 2015
Posts: 143
Likes: 0
The attraction in the ls7 is the 427 ci ready to build on i.e. the cam and heads. And avoiding opening my ls3 engine.
Last edited by VetteArts; Feb 7, 2015 at 05:19 PM.
Race Director
Joined: Aug 2005
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From: Hudson WI
NCM Sinkhole Donor
Fast Intake, NW 102 TB, Calli crank and rods.
Cam, http://www.compperformancegroupstore...de=GEN3CamsLSR
Race Director
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Option 3,
Super charge with a centrifugal supercharger and meth kit to 670hp, and you are sure to have 600rwhp with even a Automatic trans at the rear wheels.
Cost to do this, around $6K, very drivable in traffic, and all the while, on the stock motor as it sits now.
Bluntly, supercharging in the most value to dollar you can do to get HP, and about the only place that you don't want to use one, is when you are road coarse racing, where heat soak and lack of meth solution amounts will bite you instead (standard meth tank will last you less than a hour on road course track with the motor being push that long).
Super charge with a centrifugal supercharger and meth kit to 670hp, and you are sure to have 600rwhp with even a Automatic trans at the rear wheels.
Cost to do this, around $6K, very drivable in traffic, and all the while, on the stock motor as it sits now.
Bluntly, supercharging in the most value to dollar you can do to get HP, and about the only place that you don't want to use one, is when you are road coarse racing, where heat soak and lack of meth solution amounts will bite you instead (standard meth tank will last you less than a hour on road course track with the motor being push that long).
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Thread Starter
Instructor
Joined: Feb 2015
Posts: 143
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Option 3,
Super charge with a centrifugal supercharger and meth kit to 670hp, and you are sure to have 600rwhp with even a Automatic trans at the rear wheels.
Cost to do this, around $6K, very drivable in traffic, and all the while, on the stock motor as it sits now.
Bluntly, supercharging in the most value to dollar you can do to get HP, and about the only place that you don't want to use one, is when you are road coarse racing, where heat soak and lack of meth solution amounts will bite you instead (standard meth tank will last you less than a hour on road course track with the motor being push that long).
Super charge with a centrifugal supercharger and meth kit to 670hp, and you are sure to have 600rwhp with even a Automatic trans at the rear wheels.
Cost to do this, around $6K, very drivable in traffic, and all the while, on the stock motor as it sits now.
Bluntly, supercharging in the most value to dollar you can do to get HP, and about the only place that you don't want to use one, is when you are road coarse racing, where heat soak and lack of meth solution amounts will bite you instead (standard meth tank will last you less than a hour on road course track with the motor being push that long).
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
I do track days and since I am not a very good driver, I always sign up for a slow class and take an instructor. The 416 scared the hell out of my instructor (he is a spec Miata driver) and the 3:73 gears, "woke it up" a bunch.
Melting Slicks
Joined: Jun 2005
Posts: 2,396
Likes: 52
From: Sicamous BC
I did the LS3 stroker & with 10* overlap & extensively modified cathedral heads. Its very driveable & explosive power wise, easily 600rw....bad part was "very expensive".
I also did the LW clutch flywheel set up & did not like it at all, so its is back to a not so lite & not as heavy version. A very street friendly RST.
Re cam'd last fall, down to 5* overlap, I'm trying for perfect driveability. As well I would to like soften how the motor hits, with the 4:10's it is a little unnerving in fourth
I also did the LW clutch flywheel set up & did not like it at all, so its is back to a not so lite & not as heavy version. A very street friendly RST.
Re cam'd last fall, down to 5* overlap, I'm trying for perfect driveability. As well I would to like soften how the motor hits, with the 4:10's it is a little unnerving in fourth
Race Director
Joined: Aug 2005
Posts: 13,592
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From: Hudson WI
NCM Sinkhole Donor
Thanks!
Burning Brakes
Joined: Jul 2014
Posts: 757
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From: Tracy CA
If 10.5 in the quarter is the goal heads/cam stock bottom end ls3 would get you there no problem. Im cam only ls3 a6. Stock heads and stock intake manifold and do a 10.7 and am still getting the shifts dialed in so it has more left in it. If 600whp is the more important goal Id vote 416ci.
Melting Slicks
Joined: Jun 2005
Posts: 2,396
Likes: 52
From: Sicamous BC
It wasn't easy, a little out of the box thinking from the traditional CF & LS1 Tech forums. It's getting the cylinder heads(I'm on the second set) to do the work rather than the Donkey style cam, I'm one #3 in this motor. The little things help as well, under drive pulley, EWP & a complete 3" exhaust with cats BTW. FAST 102 ported, NW 102 TB & a C6 LS7 from Haltech.
The last time I hit dyno with my street tune the first run was 596 if I remember correctly, we left off @ 604 with only a few runs. That was MAF only, then we ran it in SD with a lot less timing still running 604. There was some valve train instability so we didn't spin it higher.
Did I mention it is very expensive to get here
The last time I hit dyno with my street tune the first run was 596 if I remember correctly, we left off @ 604 with only a few runs. That was MAF only, then we ran it in SD with a lot less timing still running 604. There was some valve train instability so we didn't spin it higher.
Did I mention it is very expensive to get here
Race Director
Joined: Aug 2005
Posts: 13,592
Likes: 187
From: Hudson WI
NCM Sinkhole Donor
It wasn't easy, a little out of the box thinking from the traditional CF & LS1 Tech forums. It's getting the cylinder heads(I'm on the second set) to do the work rather than the Donkey style cam, I'm one #3 in this motor. The little things help as well, under drive pulley, EWP & a complete 3" exhaust with cats BTW. FAST 102 ported, NW 102 TB & a C6 LS7 from Haltech.
Did I mention it is very expensive to get here
Did I mention it is very expensive to get here
Thread Starter
Instructor
Joined: Feb 2015
Posts: 143
Likes: 0
It wasn't easy, a little out of the box thinking from the traditional CF & LS1 Tech forums. It's getting the cylinder heads(I'm on the second set) to do the work rather than the Donkey style cam, I'm one #3 in this motor. The little things help as well, under drive pulley, EWP & a complete 3" exhaust with cats BTW. FAST 102 ported, NW 102 TB & a C6 LS7 from Haltech.
The last time I hit dyno with my street tune the first run was 596 if I remember correctly, we left off @ 604 with only a few runs. That was MAF only, then we ran it in SD with a lot less timing still running 604. There was some valve train instability so we didn't spin it higher.
Did I mention it is very expensive to get here
The last time I hit dyno with my street tune the first run was 596 if I remember correctly, we left off @ 604 with only a few runs. That was MAF only, then we ran it in SD with a lot less timing still running 604. There was some valve train instability so we didn't spin it higher.
Did I mention it is very expensive to get here
What specific under drive pulley and EWP you had?
What porting level too?
I would appreciate some details as this thread will be good reference going forward.
Thread Starter
Instructor
Joined: Feb 2015
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If 10.5 in the quarter is the goal heads/cam stock bottom end ls3 would get you there no problem. Im cam only ls3 a6. Stock heads and stock intake manifold and do a 10.7 and am still getting the shifts dialed in so it has more left in it. If 600whp is the more important goal Id vote 416ci.
Melting Slicks
Joined: Jun 2005
Posts: 2,396
Likes: 52
From: Sicamous BC
The porting I would call extreme, the heads were ordered as a rough casting TF 235. This is so the head guy can do his own porting, both CNC & hand finish. The reason? final port does not end up huge killing air speed, port size finished 237. Compression is 11.5.
I choose Cathedral heads over LS3 @ that time as I wanted a hard hitting explosive motor. Debates back then & solid LS3 porting was up in the air, as well, this was my second cylinder head purchase as the first set had been very disappointing to say the least(brand name & ported by the big name). At that same time I was on the second cam shaft, the first cam was 17* with the first set of heads I was rewarded a dismal 518rw & the worst manners ever
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I did consider supercharging but it will take me another class in drag races where SC alone will not be enough to win competition. I would then need some internals which may include a pistons and bearings. Therefore if I will end up opening the bottom end I would go stroker and get higher torque.
Hate to say it, but the stock motor will get you where you want to be. So stop focusing on it, and instead focus on getting out of the hole hotter instead. You need to bullet proof the drive line so you can get more grip via the tires, and not blow the drive line up in the process of putting that new grip to use. Also gearing is huge is here as well.
Hence no reason to try to make up time after the 60 by throwing more HP at that, when its the 60ft times that you need to focus on instead for the quicker passes instead.
Or just sell the vet, and buy a smart car instead,
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Yes it is a 416 stock bore 4" stroke. I don't remember the specifics of the under drive other than I did it twice, the APS wobbled, currently it is a Power dyne. The EWP is a Meziere @ that time I was planning to Auto X, would have been a nice to cool down in between.
The porting I would call extreme, the heads were ordered as a rough casting TF 235. This is so the head guy can do his own porting, both CNC & hand finish. The reason? final port does not end up huge killing air speed, port size finished 237. Compression is 11.5.
I choose Cathedral heads over LS3 @ that time as I wanted a hard hitting explosive motor. Debates back then & solid LS3 porting was up in the air, as well, this was my second cylinder head purchase as the first set had been very disappointing to say the least(brand name & ported by the big name). At that same time I was on the second cam shaft, the first cam was 17* with the first set of heads I was rewarded a dismal 518rw & the worst manners ever
The porting I would call extreme, the heads were ordered as a rough casting TF 235. This is so the head guy can do his own porting, both CNC & hand finish. The reason? final port does not end up huge killing air speed, port size finished 237. Compression is 11.5.
I choose Cathedral heads over LS3 @ that time as I wanted a hard hitting explosive motor. Debates back then & solid LS3 porting was up in the air, as well, this was my second cylinder head purchase as the first set had been very disappointing to say the least(brand name & ported by the big name). At that same time I was on the second cam shaft, the first cam was 17* with the first set of heads I was rewarded a dismal 518rw & the worst manners ever
What cam numbers are you running now.?
How much cfm does the intake port let in? 365?