Blended BR285s (12degree), Ported MSD, Stroked w/.720” lift cam
#41
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Good move keeping it oversquare. I done undersquare motors in trucks but much prefer oversquare for most uses
#42
I talked extensively with Anthony Forney and Erik Koenig at Horse Power Research, before pulling the trigger on my LS7 based 468 stroker.
For a max effort N/A motor, the Darton sleeves were more than capable of supporting my needs. I went forward with using my original usable LS7 block for this project, to take advantage of the bay to bay breathing abilities. I had the option of saving a few dollars and going with the 5.3 option, but nostalgia and using my original motor won out
Going out to 4.185 bore on a stock sleeved motor is usually not recommended, but many have successfully built motors using this exact setup. The Dart iron sleeve adds significant strength and limits bore distortion. HPR sells this 468 as a max effort N/A setup....no boost or spray, as the custom pistons required for this stroker crank setup expose the upper rings to the combustion process much greater.
HPR prides themselves in selling the appropriate hardware based on the customer's wants and needs........ no big expenditures or big ticket items that are not needed.
They'll sell you a LSXR block, but they'll also tell you if and when they think one is needed.
From what I've learned from experts I've talked too, head deck thickness is more important than the 6 bolt head configuration when talking about head gasket issues and lifting heads on moderately boosted engines.
For a max effort N/A motor, the Darton sleeves were more than capable of supporting my needs. I went forward with using my original usable LS7 block for this project, to take advantage of the bay to bay breathing abilities. I had the option of saving a few dollars and going with the 5.3 option, but nostalgia and using my original motor won out
Going out to 4.185 bore on a stock sleeved motor is usually not recommended, but many have successfully built motors using this exact setup. The Dart iron sleeve adds significant strength and limits bore distortion. HPR sells this 468 as a max effort N/A setup....no boost or spray, as the custom pistons required for this stroker crank setup expose the upper rings to the combustion process much greater.
HPR prides themselves in selling the appropriate hardware based on the customer's wants and needs........ no big expenditures or big ticket items that are not needed.
They'll sell you a LSXR block, but they'll also tell you if and when they think one is needed.
From what I've learned from experts I've talked too, head deck thickness is more important than the 6 bolt head configuration when talking about head gasket issues and lifting heads on moderately boosted engines.
#43
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If you are staying n/a resleeving an alum 5.3 is the most cost effective and lightest... otherwise if you plan to spray/boost it the 6 bolts per cylinder head style aftermarket block is better.... Stay away from the RHS block as they have had many issues with porosity/leaking in the blocks. LSx iron block weighs an additional 130lbs+ over a factory aluminum.....
Building a big cubic inch n/a motor that really works is $$$$$$. Killer cylinder heads and aftermarket rocker arms alone are big coin.
Building a big cubic inch n/a motor that really works is $$$$$$. Killer cylinder heads and aftermarket rocker arms alone are big coin.
I so hope this is true!!! Lol. Time will tell
#44
Crower is one of the best with there steel* shaft mounted rockers.....will be using a Crower 1.9 ratio for ls7 heads
Stud mounted rockers can handle higher lifts if u know what to do....Tap for a larger stud and change trunnion for larger studs. Weld up guide plates *if needed. Used Comp cams adjustable stud mounted RR.
I'm at 730 lift on both sides with a stud ..Guy who showed and taught me has used over 800 lift. Works with ls3 and ls7 heads. And rocker stud guirdle. 1800 vs 700 and a little bit of thinking not straight OTB.
Stud mounted rockers can handle higher lifts if u know what to do....Tap for a larger stud and change trunnion for larger studs. Weld up guide plates *if needed. Used Comp cams adjustable stud mounted RR.
I'm at 730 lift on both sides with a stud ..Guy who showed and taught me has used over 800 lift. Works with ls3 and ls7 heads. And rocker stud guirdle. 1800 vs 700 and a little bit of thinking not straight OTB.
#45
Crower is one of the best with there steel* shaft mounted rockers.....will be using a Crower 1.9 ratio for ls7 heads
Stud mounted rockers can handle higher lifts if u know what to do....Tap for a larger stud and change trunnion for larger studs. Weld up guide plates *if needed. Used Comp cams adjustable stud mounted RR.
I'm at 730 lift on both sides with a stud ..Guy who showed and taught me has used over 800 lift. Works with ls3 and ls7 heads. And rocker stud guirdle. 1800 vs 700 and a little bit of thinking not straight OTB.
Stud mounted rockers can handle higher lifts if u know what to do....Tap for a larger stud and change trunnion for larger studs. Weld up guide plates *if needed. Used Comp cams adjustable stud mounted RR.
I'm at 730 lift on both sides with a stud ..Guy who showed and taught me has used over 800 lift. Works with ls3 and ls7 heads. And rocker stud guirdle. 1800 vs 700 and a little bit of thinking not straight OTB.
Most durable material you can get.
#46
Crower is one of the best with there steel* shaft mounted rockers.....will be using a Crower 1.9 ratio for ls7 heads
Stud mounted rockers can handle higher lifts if u know what to do....Tap for a larger stud and change trunnion for larger studs. Weld up guide plates *if needed. Used Comp cams adjustable stud mounted RR.
I'm at 730 lift on both sides with a stud ..Guy who showed and taught me has used over 800 lift. Works with ls3 and ls7 heads. And rocker stud guirdle. 1800 vs 700 and a little bit of thinking not straight OTB.
Stud mounted rockers can handle higher lifts if u know what to do....Tap for a larger stud and change trunnion for larger studs. Weld up guide plates *if needed. Used Comp cams adjustable stud mounted RR.
I'm at 730 lift on both sides with a stud ..Guy who showed and taught me has used over 800 lift. Works with ls3 and ls7 heads. And rocker stud guirdle. 1800 vs 700 and a little bit of thinking not straight OTB.
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Finally!
#54
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Personally I stopped looking into flow numbers for some debatable reasons. I noticed the use clay to gain some CFM again it's normal I'd say and also wonder what bore is the plate they are flowing it as well. If they flow that at a 4.125 I'd like to see what they flow on a 4.185 bore for the OP bore spacing. I'd like to see them on engine dynos tho. Looks pretty good so far.
#58
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Their stock ls7 data is on the extreme high end of anything I've ever seen. At least on the intake side. Exhaust numbers are reasonable.
The gains over stock are quite solid. Probably some of that is to do with the larger valve. Stalling at .740" definitely shows they aren't lying about it being a smaller runner.
The gains over stock are quite solid. Probably some of that is to do with the larger valve. Stalling at .740" definitely shows they aren't lying about it being a smaller runner.
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They used a 4.155 bore plate vs a 4.125. That may be why.