DearmanLS1

iTrader: (8)

Okay so I am trying to find out if it is possible to put LS3 heads and Intake on an LS1. I know that you would have to do both in order because the LS6 intake does not match with the ls3 heads. A lot of people have told me no because of the throttle body. But a few weeks ago I was talking to this guy and he said that he did it on his LS1. He said basically the issue is the TB but Eddelbrock (I apologize if that is not spelt right) makes a TB that will match up with the LS3 intake and work for an LS1. He said other than that the only other thing I will need is an additional temp sensor or a plug because the LS3 heads have a temp sensor on both heads. So I would just like to get confirmation that you can do this, and if so is there any other details he left out? I know the LS3 heads/intake flow MUCH better than the 243/ls6 setup and aren't much more expensive. Thank you!

redtan

iTrader: (5)

The regular LS3 heads will not fit the LS1 block period regardless of the intake or throttle.

If you get some worked LS3 heads made for the LS1 block (small bore heads) you will be able to physically fit them on the block itself.

DearmanLS1

iTrader: (8)

ah really now? hmm do you think its worth it to go down the LS3 road or just stick with ported 243s and the LS6

xBoostx

it has it all, correct flow combustion chamber volume you name it...

Cause YOLO= you only live once.

Rectangular Port LS3 11 Degree Small Bore CNC Assembled (3.900"-3.960" Bore)
P/N 510-301
Retail: $1299.99 ea

• Easy bolt on to convert your GM Gen III to GM Gen IV head technology
• Perfect for LS1 and LS6 engines and short-blocks
• Accepts LS3/L92 valvesprings, rocker arms, and intake manifolds
• Outflows any aftermarket cathedral cylinder head on the market
• Uses a 2.080" intake valve and 1.570" exhaust valve
• Has a 63cc combustion chamber standard
• Has a deck thickness of .750"

Each Mast Black Label cylinder head assembly includes:

• A fully CNC machined Mast Black Label aluminum cylinder head
• Mast micro finished .650 lift beehive valve springs
• Mast lightweight stainless steel intake & exhaust valves
• Mast lightweight steel retainers
• Mast machined locks
• • NOTE: Gaskets, valve covers, rocker arms and pushrods not included
Flow Data w/3.900" Bore Plate
Lift Intake Exhaust
0.100 72 55
0.200 148 107
0.300 224 155
0.400 282 203
0.500 322 214
0.550 338 222
0.600 342 227
0.650 346 231
0.700 353 257

Mast Motorsports : High Performance Powertrain Solutions
To order or for more info (936) 560-2218 or info@mastmotorsports.com

redtan

iTrader: (5)

If you got the money for those MAST heads then yeah it will be worth it over a set of ported 243s.

But if you're going to drop that much coin on heads, you should look at other cathedral port options from AFR or TFS.

KCS

iTrader: (20)

Ballistic is a sponsor here that was putting LS3 castings on the 3.9" bores, and they turned down the valves to make it fit, so it costs a lot less. I still think the port is too big for that kind of application, but thats the more budget friendly option if you decide to go that route.

DearmanLS1

iTrader: (8)

SO since these are rectangular ported LS3s will they fit with just an LS6 intake?

LS1MCSS

iTrader: (18)

Nope, cathedral port intake will not work with rectangle port heads.

2000ultraZ1911

I don't think it'd be worth it there TEA does some very impressive numbers with 243s

xBoostx

Use ls3 intake perfect for the Mast heads.

427zm

iTrader: (9)

OP, I'd love to see results w/ either the ballistic speed LS3's, or the Mast small bores. Many don't think the square ports will work well w/ anything less than the 4" bore, but Mast and Ballistic will tell you different. It's sure hard to not look at these heads real hard b/c they flow so well, but you won't find results out there, and I think that's why people are tentative about them. Published results will change or keep reluctance in the market depending on the numbers.

Subscribed, and in to see results if you try them out.

I agree, YOLO.

But, it's an expensive test if it doesn't pan out well.

redtan

iTrader: (5)

Port shape has nothing to do with it...most people think that the large 2.165 valves don't work well with a 4" bore. But since those heads have smaller 2.080 valves it will be fine.

DearmanLS1

iTrader: (8)

yeah, I was just looking for a setup that makes over 420 whp in a stalled auto. so if you guys got any ideas of the best flowing heads, I know ported 243s are damn good, but to by honest here, my buddy has a stalled auto and he went with a street sweeper and ported 243s with an ls6 intake and he put down 416 on the dyno, lol just trying to get an edge over him.