Michael's New LS 807hp on Pump Gas Naturally Aspirated

Michael wanted to get the same power on motor as he had been getting from the bottle. And he wanted to stick with an aluminum engine. This 427ci LS got the job done for him with 807hp using an RHS - Racing Head Service aluminum block. Watch the video to see the dyno and build details.
Borowski Race Engines, Inc.
Joliet Illinois
Tel: [phone]
[e-mail]
www.borowskirace.com

[@onecargarage7621]

Placing my order here in a few months. Looking forward to working with you.

[@borowskirace]

That sounds great! What is your ride?

[@danmyers9372]

That’s amazing power out of an NA LS small block. Guessing it must have been pretty large ci (454?), high CR and a really big cam.

[@borowskirace]

Hi Dan. The displacement of this engine is 427ci (4.125" bore, 4.00" stroke). It has a very streetable hydraulic roller cam and a pump gas type CR. The power we get is a result of our machining, parts, selection and tune done on our dyno. For example, the heads are All Pros which we machine from raw porter castings. The fininshed heads therefore have our port and combustion chamber designs with all machining done either on our 5-axis Rottler CNC or 2-axis Newen CNC seat & guide machine. You'll notice that peak horsepwoer is at 6,800 rpm. This is thanks in good measure to our use of a shaft rocker system to better stabilize the hydraulic roller valve train. You can learn more about our machining on our TH-cam Engine Machining playlist. Here is a link to more details on this engine: borowskirace.com/collections/ls-street-engines/products/800-hp-427-ci-aluminum-hydraulic-roller-ls-engine-for-road-and-track?variant=39270632456366

[@thatmand4542]

@@borowskirace hello guys i wanted to ask since id like to do a similar build,i wanted something that could take 87 octane pump gas and still run 700 hp or so,so will this setup be safe to run on 87 pump all day everyday
i was also thinking about doing a small block chevy dart block build with 427ci,id like this since its going in a 76 square body and i would like to keep it period correct and this truck will be a daily driver as well
what's yall's take on it ?

[@vanilla_jupiter]

​@@thatmand4542 87 octane just won't work bro, with 87 you are looking at compression ratio of 8.0:1 or less. You just can't get enough power with that kind of compression ratio not even mention 700hp. In this situation you just can't get the best of the both worlds.

[@borowskirace]

@Daniel Ortego For some reason, your comment is only partially showing on our notifications and not showing at all here. As custom engine builders, we can easily switch you to one of our more aggressive cams. Since I can't see all of you comment, I can only guess what else is on your list. Best is to call us and discuss your list. 815-725-2727.

[@lancelanphier9509]

Very nice horsepower number.
Did this thing fall off on horsepower at the big end because it was recording the dyno slowing down and or letting off, or because it didn't have any more camshaft to benefit?
(Seems like that engine would have easily sung past 8,000 and beyond)

[@borowskirace]

Things are happening pretty quickly when doing a dyno pull. The technician knows what the engines capabilities and proceeds accordingly. THe will be watching the gauges and listening for the indication that peak horsepowr has been reached. By the time he reacts, he has already past peak. There is no point in over-revving past that. This build had a hydraulic roller cam and shaft COMP BSR shaft rockers. We like this set up to about 7,200 rpm. At that point, we know the valve train is stable. If we want higher rpm capbilities, it woud be a different build - mechical cam, Jesel rockers, etc. The C4 Bonneville car on our PRI booth last month was an ideal example of a high rpm build. The dyno tech took tat one up to 9,300 rpm. th-cam.com/video/4x-5BDfJ9Sc/w-d-xo.htmlsi=KuUofBbKs3peg8Ez

[@lutherjackson_]

Wow! Could you get close to that number with an Iron Block?

[@borowskirace]

HI. Using an aluminum block for this build does not change the expected horsepower versus say a Dart LS Next iron block using the same parts. The main reason that Michael wanted aluminum was the 100 lb weight savings. In drag racing, the key metric for going fast isn't horsepower, it's weight to horsepower. That being said, he'd only be gaining the equivalent of about 25 horsepower from aluminum's weight savings. That gain however comes for a fairly hefty upcharge. He also raced autocross. Pulling 100 lbs out of the nose of a Camaro is a really big deal for handling and braking. Aluminum is therefore great for autocross and road racing. Another benefit aluminum brings to the party is better cooling. That is much more important in road racing due to the long duration. It also can be a factor in the car build as a smaller car may not have a lot of space for radiators adequate to the task. More horsepower = more heat. Hope that answers your question.

[@borowskirace]

Thanks for the comment. We tend to make MORE power with the iron blocks than the aluminum. Not a lot, but we attribute it to the steel blocks keeping their shape better than the aluminum blocks. On that combination, it might only be 5-10HP, but it's not less. The people buying this combination are happy to trade 5HP for the 110lb of weight savings.

[@tonkatoytruck]

What can you get with an LM7 383 on E-85 and 13:1 ? I am trying to decide if custom pistons are worth my effort.

[@TheNumbers400]

What would something like this do had it compression to run on C16 or similar?

[@Giftied]

im assuming the msd is ported and a 103mm throttle body?

[@borowskirace]

The MSD was not ported. It had the satndard 103mm throttle body.

[@SoftiesTruck]

Wow what compression is this engine?

[@borowskirace]

For competitive reasons, we don't release all the details of our builds (cam specs, tune, CR, etc.) . Our machining of the combustion chamber affects how detonation occurs. Thus, a head with the same size combustion chamber might knock where ours would not under identical conditions. The tunes we use are ones that we have been tweaking for a long time. A bad tune tune will knock even with a low CR. That being said, you'll want to run premium gasoline.

[@tonkatoytruck]

@@borowskirace I'll take a guess around 11.5:1, since you can not say. Very impressive, all the same. Thanks for sharing.

[@tlovsoe4211]

@@borowskirace that is a shame

[@lightningjohnson7065]

Does Michael have a TH-cam page?

[@borowskirace]

I am not aware of him having an social media channels

[@MohMoh-mi2wu]

What is a cam stags ?

[@borowskirace]

I suspect that "stags" is a typo and you meant "stages". Some vendors identify their cams by Stages (ex 1, 2, 3). It allows them to easily sell cams to customers and applications from a limited inventory. We don't use stage designations but rather go more with custom cams by specific application. We also don't publish cam specs on our builds or advertise cams for sale as we consider proprietary the knowledge embedded in the cams we use.

[@robertbailey3057]

If someone where to come to you with all of their builds information would you make a custom cam? Obviously specs would be with held.

[@Gregoman89]

Compression ratio?

[@borowskirace]

Thanks for your question, but that falls into secret sauce territory, We don't publish CR, cam specs, tune details, etc. That is both for competitive reasons and to avoid online discussions about why we are using the wrong combinations. Our street/strip engines are set up for 93 octane unless otherwise noted (ex. 91 octane for west coast).

[@TheYamaha37]

NA motor could benefit from a vacuum pump alot.