402 Stroker Results (came up slightly short) - NA experts step inside
04-03-2013, 08:12 PM
#1
On The Tree
Thread Starter
402 Stroker Results (came up slightly short) - NA experts step inside 5/1/13 (holy SLOW-***** Batman!) finally uploaded my dyno graph! At bottom of this post...
Took eons to get graph from tuner, and another 2 weeks for me to get it transported onto laptop and into photoshop to resize.
Blue line is my old setup with PRC LS6 heads and MS4 cam. Greenish lines are the TFS 235s and current 243/251 cam.
Graphs will look peaky because of how Dynapack charts them. Keep that in mind as a Dynojet curve will look way prettier and broader.
Details below in OP...
4/9/13 - updates on my findings in Post #32 for the missing power, and post 35 for the final report (along with a 'victory close') .
4/4/13 UPDATE:
-Added pics because this thread is looking dull...
-A good GTO pal has a 3" magnaflow catback (custom true 3" not their necked down competition unit), we are going to swap next week and look for improvements. This is a truly great friend for lending me his exhaust!
-May purchase a 3" catback when I have the coin, torn between building my own w/Bullets again vs buying a clean mandrel bent expensive setup like this: http://marylandspeed.com/kooks-stree...06-p-2870.html
-Will probably sell my 92 for a 102 and port match that correctly to the smaller ports on my 235s (still staggered by the narrow width of the 235 runners)
-Will top off the combo with a GZ vacuum pump end of this year unless someone cautions me otherwise. They seem to have the best performing kit that can be bolted on in a day headache free for a GTO. I like having NO gasket leaks for a change and would like to keep it that way!
Determined to hit my goal with stock WP...
Thank you to EVERYONE who has posted up intelligent thoughts, feedback and support. You guys are great and helped make this build possible by letting me study your successes and frustrations over the years as I pieced this thing together. :salute:
ORIGINAL POST:
I don't post very often on here, just research, but I need help from the veterans on here like Excessive, Spinmonster, Cray and others.
I don't have a copy of the dyno yet but I will have it posted by next week, along with the MAP tables so we can examine the kPA values for intake and flow restriction.
Motor is a 402ci aluminum LS2 in a 2005 GTO with a built M6 and lots of weight reduction (curbs 3490# with two Corbeau front seats, retains heat/AC/stereo, half tank gas and no driver). Driver is a 225# fat *** who eats too much and needs human weight reduction mods...
402 is a TSP shortblock with everything else set up by me (15 years automotive experience).
Car started life as a fun street car and has progressed to weekend warrior and track-car for auto-x, HPDEs, and occasional drag racing.
My goal with this motor (in its current form with top-shelf parts) was 550whp/505wtq NA, with a usable 7000rpm of power. These were not arbitrary numbers, mind you. I have seen numerous 402-408s with TFS 225s hit 540whp or better with the right parts and rev to 6800, so with TFS 235s and some very special custom work by Brian Tooley himself, I did not see 550whp being an issue. I wanted a max-effort LS2 stroker that retained a streetable torque curve and would raise eyebrows of many LS7 owners.
...Tuned by Reckart Performance in Cedar Park, TX on 3/22/13...motor made 535whp/501wtq, NA, SAE on 93-pump on a Dynapack through stock 3.46 rear. SO CLOSE!!!!
Please look over the specifics of the build and let me know where you thing I can gain the missing 15whp and 500rpm without breaking out another grand...
-402ci LS2 with -8cc Wisecos, plasma moly rings gapped at .022"
-ARP 2000 rod bolts, ARP crank bolt
-ATI super damper 10% UDP
-Stock WP
-TFS 235s with custom shallow chamber setup (63cc), then milled to 58cc for 12:1 SCR w/Cometic .045" gaskets
-Heads were hand-polished by Brian Tooley to reduce hot spots in the chambers, stave detonation, and were custom built with powdered metal valve guides to facilitate stock rocker arms (YTs and Scorpions fail constantly)
-Comp Cams trunion upgrade to stock RAs
-243/251 113* LSA cam on LSL lobes (cam was spec'd specifically for these heads and my power goals)
-C5R timing chain (because the LS2 f**ker broke after 21k miles with an MS4 cam)
-TSP ported LS6 oil pump
-Ported Fast 92 w/90mm LS2 TB (manifold was port-matched to old PRC heads, and the intake ports are wider than the current intake runners on TFS 235s...if that helps)
-NGK TR6 plugs gapped at .040", MSD plug wires
-Vararam intake, no MAF, SD-tuned
-Kooks 1-7/8" longtubes, 3" catted mids into 2.5" straight through catback (Dynomax Bullets and Magnaflow X-pipe)
That should be damn near everything.
Only things I can think of to overcome this deficit are:
-GZ vacuum pump
-3" catback (lot of debate here, some see little to no gain off this NA)
-sell Fast 92, buy Fast 102 and port-match the runners to my heads
-V-Max ported TB (4-5whp on this motor at most according to Mike Norris)
-EWP (not cost effective which is why I have shunned this mod...$700 for 4-5whp)
I have gone to great lengths and spent hundreds of hours researching the parts for this setup. Ron @ Vengeance, Brian Tooley of TEA, Brian Hinson of HSC and many others have all been tremendously helpful in the research phase. I just want to hit my goal so I can call the motor build complete.
Post up your thoughts and experience, or email me at: detailaddicts@gmail.com
I will post the dyno curve soon so you can all better see what is happening (or not happening).
Thanks!
-Michael
Took eons to get graph from tuner, and another 2 weeks for me to get it transported onto laptop and into photoshop to resize.
Blue line is my old setup with PRC LS6 heads and MS4 cam. Greenish lines are the TFS 235s and current 243/251 cam.
Graphs will look peaky because of how Dynapack charts them. Keep that in mind as a Dynojet curve will look way prettier and broader.
Details below in OP...
4/9/13 - updates on my findings in Post #32 for the missing power, and post 35 for the final report (along with a 'victory close') .
4/4/13 UPDATE:
-Added pics because this thread is looking dull...
-A good GTO pal has a 3" magnaflow catback (custom true 3" not their necked down competition unit), we are going to swap next week and look for improvements. This is a truly great friend for lending me his exhaust!
-May purchase a 3" catback when I have the coin, torn between building my own w/Bullets again vs buying a clean mandrel bent expensive setup like this: http://marylandspeed.com/kooks-stree...06-p-2870.html
-Will probably sell my 92 for a 102 and port match that correctly to the smaller ports on my 235s (still staggered by the narrow width of the 235 runners)
-Will top off the combo with a GZ vacuum pump end of this year unless someone cautions me otherwise. They seem to have the best performing kit that can be bolted on in a day headache free for a GTO. I like having NO gasket leaks for a change and would like to keep it that way!
Determined to hit my goal with stock WP...
Thank you to EVERYONE who has posted up intelligent thoughts, feedback and support. You guys are great and helped make this build possible by letting me study your successes and frustrations over the years as I pieced this thing together. :salute:
ORIGINAL POST:
I don't post very often on here, just research, but I need help from the veterans on here like Excessive, Spinmonster, Cray and others.
I don't have a copy of the dyno yet but I will have it posted by next week, along with the MAP tables so we can examine the kPA values for intake and flow restriction.
Motor is a 402ci aluminum LS2 in a 2005 GTO with a built M6 and lots of weight reduction (curbs 3490# with two Corbeau front seats, retains heat/AC/stereo, half tank gas and no driver). Driver is a 225# fat *** who eats too much and needs human weight reduction mods...
402 is a TSP shortblock with everything else set up by me (15 years automotive experience).
Car started life as a fun street car and has progressed to weekend warrior and track-car for auto-x, HPDEs, and occasional drag racing.
My goal with this motor (in its current form with top-shelf parts) was 550whp/505wtq NA, with a usable 7000rpm of power. These were not arbitrary numbers, mind you. I have seen numerous 402-408s with TFS 225s hit 540whp or better with the right parts and rev to 6800, so with TFS 235s and some very special custom work by Brian Tooley himself, I did not see 550whp being an issue. I wanted a max-effort LS2 stroker that retained a streetable torque curve and would raise eyebrows of many LS7 owners.
...Tuned by Reckart Performance in Cedar Park, TX on 3/22/13...motor made 535whp/501wtq, NA, SAE on 93-pump on a Dynapack through stock 3.46 rear. SO CLOSE!!!!
Please look over the specifics of the build and let me know where you thing I can gain the missing 15whp and 500rpm without breaking out another grand...
-402ci LS2 with -8cc Wisecos, plasma moly rings gapped at .022"
-ARP 2000 rod bolts, ARP crank bolt
-ATI super damper 10% UDP
-Stock WP
-TFS 235s with custom shallow chamber setup (63cc), then milled to 58cc for 12:1 SCR w/Cometic .045" gaskets
-Heads were hand-polished by Brian Tooley to reduce hot spots in the chambers, stave detonation, and were custom built with powdered metal valve guides to facilitate stock rocker arms (YTs and Scorpions fail constantly)
-Comp Cams trunion upgrade to stock RAs
-243/251 113* LSA cam on LSL lobes (cam was spec'd specifically for these heads and my power goals)
-C5R timing chain (because the LS2 f**ker broke after 21k miles with an MS4 cam)
-TSP ported LS6 oil pump
-Ported Fast 92 w/90mm LS2 TB (manifold was port-matched to old PRC heads, and the intake ports are wider than the current intake runners on TFS 235s...if that helps)
-NGK TR6 plugs gapped at .040", MSD plug wires
-Vararam intake, no MAF, SD-tuned
-Kooks 1-7/8" longtubes, 3" catted mids into 2.5" straight through catback (Dynomax Bullets and Magnaflow X-pipe)
That should be damn near everything.
Only things I can think of to overcome this deficit are:
-GZ vacuum pump
-3" catback (lot of debate here, some see little to no gain off this NA)
-sell Fast 92, buy Fast 102 and port-match the runners to my heads
-V-Max ported TB (4-5whp on this motor at most according to Mike Norris)
-EWP (not cost effective which is why I have shunned this mod...$700 for 4-5whp)
I have gone to great lengths and spent hundreds of hours researching the parts for this setup. Ron @ Vengeance, Brian Tooley of TEA, Brian Hinson of HSC and many others have all been tremendously helpful in the research phase. I just want to hit my goal so I can call the motor build complete.
Post up your thoughts and experience, or email me at: detailaddicts@gmail.com
I will post the dyno curve soon so you can all better see what is happening (or not happening).
Thanks!
-Michael
Last edited by Stang2Goat; 05-01-2013 at 09:53 AM.
04-03-2013, 10:39 PM
#5
On The Tree
Thread Starter
It's a Goat, not an f-body. 
But the other fella was right, easiest diagnosis for exhaust restriction is to drop the exhaust from mids back and re-dyno.
I neglected to mention it made 505whp and 485wtq with PRC heads through these same Kooks LTs and cats. Heads were PRC LS6 heads, stage 2.5. Real basic except for the milling to 59cc. So it's tough to say if cats are truly holding me back. They are tiny 200cell cats so not much corking there.
I will never return to catless unless I am running E85, which is rare in Austin (2 stations on far ends of town). I hated the rasp, drone, and smell of my catless mids with pump gas.
At this point, I'm leaning heavily towards this:
http://www.gzmotorsports.com/SVPK-LS...-pump-kit.html
I will contact GZ again and see what kit they recommend for my setup and goals. Want to make 650bhp on motor and lay a 150 shot on it so I can stop getting railed by GT500s and Supras.
Searching for threads on the vacuum pump LS users here to see any good and bad real-world.
Thank you to everyone who has contributed so far!
But the other fella was right, easiest diagnosis for exhaust restriction is to drop the exhaust from mids back and re-dyno.
I neglected to mention it made 505whp and 485wtq with PRC heads through these same Kooks LTs and cats. Heads were PRC LS6 heads, stage 2.5. Real basic except for the milling to 59cc. So it's tough to say if cats are truly holding me back. They are tiny 200cell cats so not much corking there.
I will never return to catless unless I am running E85, which is rare in Austin (2 stations on far ends of town). I hated the rasp, drone, and smell of my catless mids with pump gas.
At this point, I'm leaning heavily towards this:
http://www.gzmotorsports.com/SVPK-LS...-pump-kit.html
I will contact GZ again and see what kit they recommend for my setup and goals. Want to make 650bhp on motor and lay a 150 shot on it so I can stop getting railed by GT500s and Supras.
Searching for threads on the vacuum pump LS users here to see any good and bad real-world.
Thank you to everyone who has contributed so far!
04-03-2013, 10:42 PM
#6
On The Tree
Thread Starter
Trending Topics
04-03-2013, 10:46 PM
#8
On The Tree
Thread Starter
For the 7000rpm goal I am probably going to have to. Just sucks because...
http://marylandspeed.com/kooks-stree...06-p-2870.html
No affordable true 3" exhausts for Goats. I priced it out and even with me buying the same parts in a 3" configuration and paying someone to weld it all up, I am still gonna spend $650-700.
Decisions...
The hesitation is like anyone who has worn these shoes...not wanting to spend mad bucks for small to no gains.
I will keep everyone posted. Can't get back to the dyno until late next week due to working 2.5 jobs.
http://marylandspeed.com/kooks-stree...06-p-2870.html
No affordable true 3" exhausts for Goats. I priced it out and even with me buying the same parts in a 3" configuration and paying someone to weld it all up, I am still gonna spend $650-700.
Decisions...
The hesitation is like anyone who has worn these shoes...not wanting to spend mad bucks for small to no gains.
I will keep everyone posted. Can't get back to the dyno until late next week due to working 2.5 jobs.
04-03-2013, 11:25 PM
#9
FormerVendor
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I would def look into either a ported by Brian FAST102 or even a Edelbrock Pro-Flow. The torque is there and just needs to breath a little better in the upper RPM's to attain your goal. Between the restrictive exhaust and the less desireable FAST92 I believe those two items are your current restriction.
If you like your exhaust currently then I would have some nice cutouts installed... best of both worlds at that point.
If you like your exhaust currently then I would have some nice cutouts installed... best of both worlds at that point.
04-04-2013, 06:44 AM
#11
Staging Lane
You can gain or lose 5-10 hp from dyno to dyno or even from day to day. I don't know that I'd throw any more money chasing 8-10 hp.
I went the opposite way. I have a LS3-based Vengeance 418 with all forged internals, TrickFlow 235cc heads, a medium cam (234/238 .602/.604 112 LSA), FAST 92, AR 1-7/8ths headers, etc. I had it tuned for mid-range power and torque. I probably gave away a few hp at the top end, but it was noticably stronger all across the powerband below 5500 rpm. It's making 525 rwhp and 490 fptq.
My car is an '01 Corvette coupe that gets driven only once a week or so on the street and one or two track days a month at VIR. To be honest, I don't know if I'd notice 10-15 hp more or less on the track.
I went the opposite way. I have a LS3-based Vengeance 418 with all forged internals, TrickFlow 235cc heads, a medium cam (234/238 .602/.604 112 LSA), FAST 92, AR 1-7/8ths headers, etc. I had it tuned for mid-range power and torque. I probably gave away a few hp at the top end, but it was noticably stronger all across the powerband below 5500 rpm. It's making 525 rwhp and 490 fptq.
My car is an '01 Corvette coupe that gets driven only once a week or so on the street and one or two track days a month at VIR. To be honest, I don't know if I'd notice 10-15 hp more or less on the track.
04-04-2013, 07:40 AM
#12
I share your pain with this, my 416 has been a ******* dud.
Your port mis match would give me sleepless nights, I can just see the weird turbulence if it was the other way, maybe.
Even as your combination is your wheel torque seems high, that's alright if all your comparisons are on the same dyno. Gains are gains.
Currently I've a set of custom TF 235's that sound very similar to yours, I've not been back to the dyno. My goals are similar to your's.
Your port mis match would give me sleepless nights, I can just see the weird turbulence if it was the other way, maybe.
Even as your combination is your wheel torque seems high, that's alright if all your comparisons are on the same dyno. Gains are gains.
Currently I've a set of custom TF 235's that sound very similar to yours, I've not been back to the dyno. My goals are similar to your's.
Last edited by ctd; 04-04-2013 at 09:41 AM.
04-04-2013, 07:41 AM
#13
On The Tree
Thread Starter
These are all good suggestions. James thank you for jumping in on this one! Your Camaro build on motor and bottle is what I aspire to. I just don't want to make the leap to a full-on carb style intake manifold - pricey swap and I would have to cut my hood up.
I have seen nothing but good things on the 102, but I will be stuck rocking my lightly ported LS2 TB since I don't have $600 laying around for a NW 102 unit.
Is $750 shipped too much to ask for a ported Fast 92 with hardware that is all cleaned up? I ask because that will cover most of the cost switching to the Fast 102 on my setup.
I have seen nothing but good things on the 102, but I will be stuck rocking my lightly ported LS2 TB since I don't have $600 laying around for a NW 102 unit.
Is $750 shipped too much to ask for a ported Fast 92 with hardware that is all cleaned up? I ask because that will cover most of the cost switching to the Fast 102 on my setup.
04-04-2013, 07:43 AM
#14
On The Tree
Thread Starter
I sure your pain with this, my 416 has been a ******* dud.
Your port mis match would give me sleepless nights, I can just see the weird turbulence if it was the other way, maybe.
Even as your combination is your wheel torque seems high, that's alright if all your comparisons are on the same dyno. Gains are gains.
Currently I've a set of custom TF 235's that sound very similar to yours, I've not been back to the dyno. My goals are similar to your's.
Your port mis match would give me sleepless nights, I can just see the weird turbulence if it was the other way, maybe.
Even as your combination is your wheel torque seems high, that's alright if all your comparisons are on the same dyno. Gains are gains.
Currently I've a set of custom TF 235's that sound very similar to yours, I've not been back to the dyno. My goals are similar to your's.
PM me about your setup and dyno #s. I have seen 416s sink and swim depending on the heads/cam. I would love to have your 4.070" bore!
04-04-2013, 08:41 AM
#16
On The Tree
Thread Starter
I don't have enough posts to sell stuff on here sadly... :-(*
I am tired of dealing with the 'kidiots' on LS1GTO. Bet the Corvette Forum folks would pay good money for this intake. I keep all my parts as clean as possible and don't shortcut anything.
Been there, broken s**t and been towed home. Shame has some bit to it!
04-04-2013, 09:20 AM
#17
On The Tree
Thread Starter
Hoping my tuner is kind enough (and not swamped) to post up my dyno files from Cedar Park. I PMed him last night.
While we wait, more pics to cause smiles and laughter while raising eyebrows...
On the old setup with an MS4 cam, PRC 2.5 LS6 heads and crappy Pacesetters, car made 485whp/471wtq before I rebuilt everything.
To test/prove endurance of the setup, we drove cross country and back to visit the folks at their new home...Austin, TX to Cumming, GA (north central GA) stopping only for fuel every 350 miles. We averaged 80-85mph and clicked off 23-24mpg and came up with a dozen different rotten T-shirts utilizing the phrase 'Cumming' at the expense of my retired parents... [shameless we are]
This with 400# of Seabrooke brothers, a 55# pit bull made of love, and 250# of crap in trunk. My Pedders 5/16 drag springs and Koni shocks were an f-ing godsend! Car didn't sag or drop more than half an inch out back with all that baggage...
While we wait, more pics to cause smiles and laughter while raising eyebrows...
On the old setup with an MS4 cam, PRC 2.5 LS6 heads and crappy Pacesetters, car made 485whp/471wtq before I rebuilt everything.
To test/prove endurance of the setup, we drove cross country and back to visit the folks at their new home...Austin, TX to Cumming, GA (north central GA) stopping only for fuel every 350 miles. We averaged 80-85mph and clicked off 23-24mpg and came up with a dozen different rotten T-shirts utilizing the phrase 'Cumming' at the expense of my retired parents... [shameless we are]
This with 400# of Seabrooke brothers, a 55# pit bull made of love, and 250# of crap in trunk. My Pedders 5/16 drag springs and Koni shocks were an f-ing godsend! Car didn't sag or drop more than half an inch out back with all that baggage...
04-04-2013, 09:24 AM
#18
I definitly not an expert but I'll chime in anyway. I definitly think adding a gz pump will exceed your goals. I'm running the same cam but with tea tfs 245s on a 416. I'm also using a gz pump. My first dyno tune went 549/480 on 9" vacuum with break in oil. It was a little disappointing.
Fast forward a few months, I turned the vac up to 13" and am now on ls30 oil it put down 582/520. I'm not saying the vacuum is completely responsible but it definitly helped. I think opening your exhaust and a little vacuum will exceed your goals. Good luck!
Fast forward a few months, I turned the vac up to 13" and am now on ls30 oil it put down 582/520. I'm not saying the vacuum is completely responsible but it definitly helped. I think opening your exhaust and a little vacuum will exceed your goals. Good luck!
04-04-2013, 10:59 AM
#19
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Stang2Goat:
You can follow the details for my LS2-402 in my signature. Fairly good numbers on 93-octane with 3.73 gears and 2.50" exhaust through cats. Two differences are mine had 250cc heads with 2.10" intake valves and a somewhat larger camshaft with Harland-Sharp 1.8:1 rocker arms. Static compression was about 12.4:1.
Note: The motor is out now as a new LS2-430 with 285cc All-Pro heads is being prepared. In all honesty, I would go with their 330cc heads next time.
- Greg
You can follow the details for my LS2-402 in my signature. Fairly good numbers on 93-octane with 3.73 gears and 2.50" exhaust through cats. Two differences are mine had 250cc heads with 2.10" intake valves and a somewhat larger camshaft with Harland-Sharp 1.8:1 rocker arms. Static compression was about 12.4:1.
Note: The motor is out now as a new LS2-430 with 285cc All-Pro heads is being prepared. In all honesty, I would go with their 330cc heads next time.
- Greg
Last edited by Gregory; 04-04-2013 at 11:05 AM.
04-04-2013, 11:14 AM
#20
On The Tree
Thread Starter
I definitly not an expert but I'll chime in anyway. I definitly think adding a gz pump will exceed your goals. I'm running the same cam but with tea tfs 245s on a 416. I'm also using a gz pump. My first dyno tune went 549/480 on 9" vacuum with break in oil. It was a little disappointing.
Fast forward a few months, I turned the vac up to 13" and am now on ls30 oil it put down 582/520. I'm not saying the vacuum is completely responsible but it definitly helped. I think opening your exhaust and a little vacuum will exceed your goals. Good luck!
Fast forward a few months, I turned the vac up to 13" and am now on ls30 oil it put down 582/520. I'm not saying the vacuum is completely responsible but it definitly helped. I think opening your exhaust and a little vacuum will exceed your goals. Good luck!
582/520 on a 416 is f**king awesome. You know there are some heads/cam LS7 Z06s not touching that?
Your motor is what I would build if doing it over again, though properly ported LS3 heads from AI or TEA would be superb to run a smaller, more torque-friendly cam.
Did you run the smaller GZ pump or the larger one? They make two LSX kits and my power goals are between the two recommended HP ratings.
Post up a link or PM me with the URL for your dyno sheets if they are on here. I would love to see that nasty 416's output!