The need for more power results.427 dart shp block,ls3heads llsr cam
#1
The need for more power results.427 dart shp block,ls3heads llsr cam
So I've been working on this build for close to a year with planning and finding the right people to work with on parts.
I dont think I can mention venders if not sponsors so I'll update my signature.
dart shp iron block with k1 rods and 4" crank. Wiseco 4.125 pistons .
heads ported by Gaven Simcoe (823 ls3heads,milled to 64cc (11.8/1compression),stainless ferrera valves,pac1209x springs)
cam done by cam motion and specced by Geoff Skinner (246/262@.050-.689/.671-112lsa+2.5)
yella terra 6653 adjustable rocker arms.
for the intake I went with the Holley Sniper low profile in black. Looks bad a$$ and fit nice. Using a warr 102 throttle body(thing tuned out so nice and easy.highly recommended)
for exhaust I was reusing what I had so I wanted to make the best of it.
bassani true dual 2.5" and kooks 1-7/8"stainless headers. I loved the sound of this exhaust but I knew it would be a choke point. I used some turbo guys thinking and I wrapped my headers and xpipe to keep the heat in as much as I could. Between the llsr lifters being super quiet and the exhaust wrap, this is the quietest hot rod inside the car I have heard.
so after initially getting it running and fighting minor gremlins, I started test driving and working on idle tuning. Car drives better than my old 6.0 that made 454rwhp. The transmission was the same(stg3 200-4r rmvb with trans brake built by Lonnie Deirs).
after about 3drives with 2nd gear wot pulls the band broke and lost 2nd.
I called Lonnie and told him the situation,"no problem bud,let's upgrade you to a rmvb 4l80 with trans brake. (Awsome customer service)
so I called PTC for a converter as I wanted to trade my 2 converters I had for a single disk lock up for the 80. They built a 10" billet front cover converter . Flashed to 4600 and goes 4800 on the brake.
now to eps for dyno tuning
I had it on maf tuning for first pull just to get a base line. We maxed the maf at 5700 rpm and only made 500rwhp.
went speed Density and instantly 520 but air fuel was 10.5-11.2 so we leaned it to 12.6 and 526 rwhp with only 27 deg timing. We decided that the exhaust may be holding it back so we dropped the v bands and let the exhaust hang. I put on some 18" extension 3" pipe and finished tuning. Just from pipe it went to 535.
started going up in timing and it liked it. 31 degree timing on 93 octane fuel made 543rwhp with a curve that don't stop pulling. We stopped the pulls at 7375 but it was flat from peak hp at 6800. I'm sure I can rev to 7800 if needed but I'll find that out at the track.
I hooked exhaust back up and made a final pull to see it I got any knock from exhaust restrictions. No knock and made 538 through this 2.5" exhaust. It lost 20 through the mid range though.
the drive home and some cruises last night were fun. This thing rolls to say the least.
I will post some pictures and videos in next comment.
I dont think I can mention venders if not sponsors so I'll update my signature.
dart shp iron block with k1 rods and 4" crank. Wiseco 4.125 pistons .
heads ported by Gaven Simcoe (823 ls3heads,milled to 64cc (11.8/1compression),stainless ferrera valves,pac1209x springs)
cam done by cam motion and specced by Geoff Skinner (246/262@.050-.689/.671-112lsa+2.5)
yella terra 6653 adjustable rocker arms.
for the intake I went with the Holley Sniper low profile in black. Looks bad a$$ and fit nice. Using a warr 102 throttle body(thing tuned out so nice and easy.highly recommended)
for exhaust I was reusing what I had so I wanted to make the best of it.
bassani true dual 2.5" and kooks 1-7/8"stainless headers. I loved the sound of this exhaust but I knew it would be a choke point. I used some turbo guys thinking and I wrapped my headers and xpipe to keep the heat in as much as I could. Between the llsr lifters being super quiet and the exhaust wrap, this is the quietest hot rod inside the car I have heard.
so after initially getting it running and fighting minor gremlins, I started test driving and working on idle tuning. Car drives better than my old 6.0 that made 454rwhp. The transmission was the same(stg3 200-4r rmvb with trans brake built by Lonnie Deirs).
after about 3drives with 2nd gear wot pulls the band broke and lost 2nd.
I called Lonnie and told him the situation,"no problem bud,let's upgrade you to a rmvb 4l80 with trans brake. (Awsome customer service)
so I called PTC for a converter as I wanted to trade my 2 converters I had for a single disk lock up for the 80. They built a 10" billet front cover converter . Flashed to 4600 and goes 4800 on the brake.
now to eps for dyno tuning
I had it on maf tuning for first pull just to get a base line. We maxed the maf at 5700 rpm and only made 500rwhp.
went speed Density and instantly 520 but air fuel was 10.5-11.2 so we leaned it to 12.6 and 526 rwhp with only 27 deg timing. We decided that the exhaust may be holding it back so we dropped the v bands and let the exhaust hang. I put on some 18" extension 3" pipe and finished tuning. Just from pipe it went to 535.
started going up in timing and it liked it. 31 degree timing on 93 octane fuel made 543rwhp with a curve that don't stop pulling. We stopped the pulls at 7375 but it was flat from peak hp at 6800. I'm sure I can rev to 7800 if needed but I'll find that out at the track.
I hooked exhaust back up and made a final pull to see it I got any knock from exhaust restrictions. No knock and made 538 through this 2.5" exhaust. It lost 20 through the mid range though.
the drive home and some cruises last night were fun. This thing rolls to say the least.
I will post some pictures and videos in next comment.
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30th t/a (07-05-2019)
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#8
She got to 7200 rpm quick! Sounds great! I had to LOL at the LLSR is so quiet. it really is, but nobody believes you until they hear it first hand. I doubt I'll ever build a hydraulic valvetrain again -- at least not in my own car. If I stealth-cam my wife's I'll leave it hydraulic...
#10
Possibly. Still deciding on that and track day will help make up my mind.
It really is quiet. I need to run the valves again just to see where they are at now but have a set of custom built valve covers coming mid February. Hate to pull them and fight these spacers again
Never cared for pulling a piston out the bottom of a cylinder with 4" stroke. Plus I like cubic inches, pure preference and ability to go much wilder and bigger in the future
She got to 7200 rpm quick! Sounds great! I had to LOL at the LLSR is so quiet. it really is, but nobody believes you until they hear it first hand. I doubt I'll ever build a hydraulic valvetrain again -- at least not in my own car. If I stealth-cam my wife's I'll leave it hydraulic...
Never cared for pulling a piston out the bottom of a cylinder with 4" stroke. Plus I like cubic inches, pure preference and ability to go much wilder and bigger in the future
#11
That's cool, I absolutely understand. I hurt my turbo ls3 motor and decided to go dart lsnext shp as well. I probably could get away with a factory block but didn't want to feel limited right away. It was worth the piece of mind for me on a turbo set up. It is mega overkill for what you are doing but agree it would be nice to be able to slap a big turbo or lots of spray on it and not worry.
#12
Good numbers, I'm really surprised it like that much timing, especially with 11.8:1
The LS3 heads typically like less timing than the LS1 stuff, at least in my experience anyway.
Is this on pump gas or E?
The LS3 heads typically like less timing than the LS1 stuff, at least in my experience anyway.
Is this on pump gas or E?
#13
Its 93 pump gas. It liked it on the dyno, but it lost oil pressure on the track Sunday so not sure what happened yet. Looking at the filter vs pre dyno filter, the issue was starting already.
will have it out next week to diagnose what happened
will have it out next week to diagnose what happened
#14
Just a little update here. Number 4 main cap was tight and burnt that bearing.
Block has been line bored,decked and rehoned. New rings and bearings going in,checking the balance of the rotating assembly this week then going back together with it. Compression going up to 12.05:1 and putting on a engine dyno to break it in and look for best valve lash with this Low lash solid roller.
I'm looking at doing a GZ motorsports vacuum pump as well this time. Power should be more,the results of engine dyno will be sent with my converter to Ptc to adjust it to my set up. Then it will go back to Geoff's dyno at EPS to compare rwhp to before.
Block has been line bored,decked and rehoned. New rings and bearings going in,checking the balance of the rotating assembly this week then going back together with it. Compression going up to 12.05:1 and putting on a engine dyno to break it in and look for best valve lash with this Low lash solid roller.
I'm looking at doing a GZ motorsports vacuum pump as well this time. Power should be more,the results of engine dyno will be sent with my converter to Ptc to adjust it to my set up. Then it will go back to Geoff's dyno at EPS to compare rwhp to before.
#16
#20
There was a few things over looked on original build. This time is all about checking over every single thing several times and make sure its right.
I think it will perform much better this time,now I just need time to work on it.
I think it will perform much better this time,now I just need time to work on it.