Info wanted on Indy LA X heads

[Oldmanmopar]

I am going to look at a set of Indy LA X heads this morning. Anyone have any experience with them ? Are they a significant improvement over factory X heads ? They will be used on my left over 416 rotating assembly going into a factory block for the street performance car with all the pieces we are not using for the new build of my R-3 with indy 360-1 heads. Will they be worth the upgrade from stock X heads I have many of. He is asking $1200 Fresh?? with new PRW roller rocker assembly.

It is 7:30 here I am leaving for them at 9:00 Thanks for any info before that Steve

 

[mderoy340]

They are nice heads with a closed chamber. I bought mine from Brian IMM engines years ago. As cast the runners are smooth with almost no parting lines. They also also have large pushrod opening. I run Hughes rockers and alignment is great.

 

[408 swinger]

Sounds like a decent deal. My understanding is, they are essentially an improved Magnum head with the cast in pedestal for shaft mount and LA intake bolt pattern. They had the MA-X, which was a direct Magnum bolt on. Then the LA-X, which was for the LA series. They were supposed to be a definite improvement over any stock casting. Hughes used to have flow numbers posted for these.

 

[rmchrgr]

They are good heads. Mine were CNC ported by Brian/IMM out on California so they are certianly more capable than a non-ported set. They flow 293cfm on the intake. He didn't really touch the exhaust though if that tells you anything. Very heavy though!

On the previous iteration of my 416" they made 500 hp @ 6,000 rpm. The torque curve was flat from 4,000-6,000 and never went below 440lb ft. (See the dyno sheet below) There were a couple things holding the overall combo back but either way it would have been a pretty stout street/strip combo. Diamond dished pistons for 10.3:1 compression, 251/259 @ .050" solid cam, 1 5/8 step headers, gasket matched Holley Strip Dominator intake, OOTB Proform 850 carb.

I have a friend with an un-ported set that says they went 10.60s. Never saw a timeslip but he is a decent racer so I have no reason to doubt it.

Make sure you get the correct studs or bolts. Can't remember the part # off the top of my head but there is a specific set for them.

My dyno sheet from 2016.

 

[Locomotion]

On my Dart Sport, the LA-X heads were worth over 2 tenths in the 1/4 mile - same prep, same springs as 587 heads, both with as-cast ports. (360, .474" "Stocker" cam with lots of duration, "0" deck flattops, Holley Strip Dominator, 750 Holley,TTI 1 5/8 - 1 3/4 step headers, converter flash around 5000, 4.86 gear w/30 radials @ 3,540+ lbs.)

Differences between LA-X/587 being: 1.92/1.625 vs 1.88/1.60 valves & about 3-4cc smaller chambers. Otherwise, it was a simple swap on the same engine in the car. I don't recall if any jet tuning afterwards showed any more improvements.

RHS (Racing Head Service) was originally involved with the manufacturing & sale of these heads.

 

[MOPAROFFICIAL]

I am going to look at a set of Indy LA X heads this morning. Anyone have any experience with them ? Are they a significant improvement over factory X heads ? They will be used on my left over 416 rotating assembly going into a factory block for the street performance car with all the pieces we are not using for the new build of my R-3 with indy 360-1 heads. Will they be worth the upgrade from stock X heads I have many of. He is asking $1200 Fresh?? with new PRW roller rocker assembly.

It is 7:30 here I am leaving for them at 9:00 Thanks for any info before that Steve

Thicker casting, better exhaust port, closed chamber like a magnum, done up right with a good valve job taken to 1.98 aka 2.02 and a light bowl blend flow 270.
They came shaft Mount or stud mount. I'd say 1200 is a good deal

 

[mopar head]

Not to mention the nice flat machined valve cover gasket surface over stock Xs.

 

[Oldmanmopar]

I went to look at them and passed on them. I thought they would work for me but they won't. Compared to my indy 360-1' and my W2's the ports are small. I did like the castings though , No heat cross over and close chambered. I have a set of ported 894's from Ed Hamberger I am going to use. W2's I have are nice but I want to run manifolds. Thanks for the input, Steve

 

[gzig5]

Compared to my indy 360-1' and my W2's the ports are small.

No kidding. That's like comparing apples and watermelons. The LA-X aren't in the same class as the W2s. And I'd say a good improvement over the X head.

The LA-X would be excellent for a street performance (500HP??) car like you alluded to.

 

[MOPAROFFICIAL]

I think his ported X heads will fit the bill just fine. I know mine do..

 

[Oldmanmopar]

No kidding. That's like comparing apples and watermelons. The LA-X aren't in the same class as the W2s. And I'd say a good improvement over the X head.

The LA-X would be excellent for a street performance (500HP??) car like you alluded to.

I was hoping for some wild heads. The ports on those heads looked awfully small . More like 273 318 compared to what I am use to. The push rod bumps were pretty big in the intake ports. To me they reminded me of 308 heads and could use a lot of porting to bring them up to flowing like a standard 894 or 915 head. What I saw good was no heat cross over in the exhaust port and the heart shaped combustion chamber. They must have a high nickle content because they were heavy.

I just didn't see much improvement over the ported X heads we have from Ed Hamberger race engines .I am just going to use what I have, 894 X heads and a LD 340 intake.

 

[408 swinger]

No kidding. That's like comparing apples and watermelons. The LA-X aren't in the same class as the W2s. And I'd say a good improvement over the X head.

The LA-X would be excellent for a street performance (500HP??) car like you alluded to.

No ****. Right?! I would think if one could punch enough keys to find their way to this site, they could research what an Indy/RHS head is. Sorry, no disrespect meant to the OP. I just take it for granted that even the high rollers know what the bottom feed **** is.

 

[gzig5]

I was hoping for some wild heads. The ports on those heads looked awfully small . More like 273 318 compared to what I am use to. The push rod bumps were pretty big in the intake ports. To me they reminded me of 308 heads and could use a lot of porting to bring them up to flowing like a standard 894 or 915 head. What I saw good was no heat cross over in the exhaust port and the heart shaped combustion chamber. They must have a high nickle content because they were heavy.

I just didn't see much improvement over the ported X heads we have from Ed Hamberger race engines .I am just going to use what I have, 894 X heads and a LD 340 intake.

Your question referenced X heads for a street build. Not that you had a set of X heads breathed on by a well regarded builder in Ed Hamburger. Big difference and puts your question in a completely different context, so you can understand my confusion. Again, comparing apples to watermelons. So to the original question, I would definitely say the LA-X is still an improvement over the original X-heads and a good choice for a steel headed street build. Probably not an improvement over the modified set you have.

 

[Oldmanmopar]

Your question referenced X heads for a street build. Not that you had a set of X heads breathed on by a well regarded builder in Ed Hamburger. Big difference and puts your question in a completely different context, so you can understand my confusion. Again, comparing apples to watermelons. So to the original question, I would definitely say the LA-X is still an improvement over the original X-heads and a good choice for a steel headed street build. Probably not an improvement over the modified set you have.

I went to look at them and decided they are not for me. I have many X heads here ported and stock. The ports on these Indy x heads would need work compared to what I already have and the compression would be to high for my existing short block

They are still listed if any of you are interested. Mopar Indy X Heads

Just look like a down grade from what we already have. I want to use everything that was under my hood except the block and heads for the new street car. It was a fresh 416 and I thought I would use it all instead of buying everything again. We have many engines and parts just never had Indy X heads. Sorry for asking or offending those who have them. I think The factory ported X heads will work just fine for me.

 

[rmchrgr]

OMM no one is offended but your original question was pretty specific and we answered accordingly;

Are they a significant improvement over factory X heads?

You did not say that you had pro-level ported “X” heads on hand already so the answer is still a resounding yes, the LA/X heads are a significant upgrade over any factory iron head. Our answers to your question would have been completely different had you not left out that one particular piece of information.

I also agree that comparing W2s to the LA/X heads is not valid. As you are aware, W2s were a clean-slate design race head as opposed to a garden-variety passenger car, emissions-compliant part. Sure you can port the crap out of any factory iron head to flow decent amounts of air but it’s still a factory iron head with a pronounced pushrod pinch and standard, non-raised ports.

Your expectation of finding a “wild head” seems a bit curious since the RHS heads were marketed as a high performance factory iron replacement head - nothing wild about them and a 500hp head all day. Sorry you wasted your time but it could have been avoided with 5 minutes of research.

 

[Scampin]

What did the set of X's done by Ed Hamburg flow?

 

[Oldmanmopar]

OMM no one is offended but your original question was pretty specific and we answered accordingly;


You did not say that you had pro-level ported “X” heads on hand already so the answer is still a resounding yes, the LA/X heads are a significant upgrade over any factory iron head. Our answers to your question would have been completely different had you not left out that one particular piece of information.

I also agree that comparing W2s to the LA/X heads is not valid. As you are aware, W2s were a clean-slate design race head as opposed to a garden-variety passenger car, emissions-compliant part. Sure you can port the crap out of any factory iron head to flow decent amounts of air but it’s still a factory iron head with a pronounced pushrod pinch and standard, non-raised ports.

Your expectation of finding a “wild head” seems a bit curious since the RHS heads were marketed as a high performance factory iron replacement head - nothing wild about them and a 500hp head all day. Sorry you wasted your time but it could have been avoided with 5 minutes of research.

I only had 1 1/2 hours to do research so I thought I would ask on the site. Like I said I never laid eyes on any myself.

After looking at them the ports are not much bigger then a 318 head, I could not even get my knuckle bast the push rod bump. I was just not impressed by them in person. We have all kinds of engines and heads. B1's , Max wedge, indy Hemi, Indy max wedge, W2 , W5 and Indy 360-1, Batten rectangles, . Many many stock mopars also. I just never laid eyes on a indy -X. I am not saying they are not a good head. Just not what I am looking for to put on this build. The heads he has listed are a good deal with the rockers. Just not for me.

They would be great for a stock 318 360 bottom end to boost compression. like a 308 upgrade but a race head version.

 

[rmchrgr]

I only had 1 1/2 hours to do research so I thought I would ask on the site. Like I said I never laid eyes on any myself.

After looking at them the ports are not much bigger then a 318 head, I could not even get my knuckle bast the push rod bump. I was just not impressed by them in person. We have all kinds of engines and heads. B1's , Max wedge, indy Hemi, Indy max wedge, W2 , W5 and Indy 360-1, Batten rectangles, . Many many stock mopars also. I just never laid eyes on a indy -X. I am not saying they are not a good head. Just not what I am looking for to put on this build. The heads he has listed are a good deal with the rockers. Just not for me.

They would be great for a stock 318 360 bottom end to boost compression. like a 308 upgrade but a race head version.

About 20 years ago I had a few sets of 308 heads. I can't even give them away anymore - trust me, I've tried, no one wants them. NHRA stocker guys used to buy them up but after aluminum heads were allowed the 308s were back to being the garbage they are. They are not even worth scrapping. I also have a set of MP #269 or "574" castings which were 308 heads without the smog holes. Same deal on those plus no one even knows what they are. Totally useless.

The RHS/Indy LA-X heads were only produced for a brief time. The original Australian-cast verisons have been out of production for at least 10 years so they are actually sort of hard to find now if that means anything. They were never marketed as a race head though so I'm not sure where that idea came from. There was a time when they were very highly regarded but that was probably just internet hype and a lack of other choices.

I still have my set of of RHS heads which have only seen dyno time. They have 2.02 intake valves with I believe nice PAC springs and retainers. I considered selling them but I don't think I'd get any sort of return on them now with so many aluminum heads out there that flow enough air OOTB to support most 500-550hp builds.

It's also kinda tough to run close-chambered, iron heads on the street on pump gas with anything over 10.5:1 so that certainly limits their potential. Higher compression would certainly be helpful but then they're no longer a street head. The pistons I used with them for my old 416" combo had a lake-size dish, it was almost laughable.

And as you learned the RHS castings are very heavy. Picking them up they feel like 7-10lbs heavier than a factory iron head which is saying a lot. Unless you are racing in a class that requires iron heads they just don't make much sense to use any more. They've been on my shelf for years now and will probably stay there for many more.

 

[JDMopar]

@Oldmanmopar Steve, if your headers got mangled in the crash, there's a big tube set of small block TTI's for sale on here. They are even in PA.

[SOLD] Thread 'TTI headers for small block'

Sep 30, 2025

I ordered and purchased these directly from TTI and have probably less than 100 miles on them. These are either 1.75 or 1.875 (looking for paperwork) primaries and 3.5" collectors. They are ceramic coated and have the evac tubes.These are in excellent condition.....like new really. I'm taking the car in another direction motor wise so can't use these. A new set of collectors, gaskets and header bolts included.
I would prefer pickup over shipping.
I paid $1150 plus shipping. I would like to get $700 for everything.

• 63SplitWindow
• Replies: 9
• Forum: Mopar Performance Parts For Sale

 

[mopar head]

There was a time when they were very highly regarded but that was probably just internet hype and a lack of other choices.

I`m one who bought into the hype, IMM prepped 2.02, beehives, yada yada.
No complaints though.

 

[rmchrgr]

I`m one who bought into the hype, IMM prepped 2.02, beehives, yada yada.
No complaints though.

Hey, I did too. They were and are still a good choice for a street/strip build if cast iron is OK. As was the case 10-12 years ago there are very few iron "LA" heads out there with the same potential. IMM did a nice job on their program. Plus, I was able to initialy get the heads very cheaply due to a price match mistake by Summit. IMM was offering the CNC service at the time and it looked promising so it worked out nicely.

I actually had older #810 casting W2s on my Duster when I first got it in 2012. It was going 12.0 at 110mph on a stock stroke 340 with a MP .528" solid cam, TRW pop up pistons, untouched Victor intake and the same 1 5/8" step headers. Shifted at 7,200. They W2s had been massaged a bit but they were nothing special and needed a lot of work to reach their full potential. I'm certain that just swapping the W2s for the ported RHS while leaving everything else the same the car would have picked up a bunch.

I ultimately ended up selling all my W2 stuff a few years later for a couple hundred more than what I paid IMM for the CNC job.

 

[furrystump]

They just made them legal for FAST, I don’t agree with that decision. When the discussion was going on, I reached out to Indy and asked if they plan to start making them again. No, in the change of owners the tooling was lost and the million dollar cost to recreate it is in no way justified by the market. No one I know is running them.

 

[rmchrgr]

They just made them legal for FAST, I don’t agree with that decision. When the discussion was going on, I reached out to Indy and asked if they plan to start making them again. No, in the change of owners the tooling was lost and the million dollar cost to recreate it is in no way justified by the market. No one I know is running them.

Wow, I didn't know about the decision to allow those in your group. I've wondered about that for years and thought that class would be the one instance where they could be a good fit. 5 minutes to grind the Indy logos off and voila, you have "factory appearing" heads that flow almost 300cfm...

 

[Killer6]

I went to look at them and decided they are not for me. I have many X heads here ported and stock. The ports on these Indy x heads would need work compared to what I already have and the compression would be to high for my existing short block

They are still listed if any of you are interested. Mopar Indy X Heads

Just look like a down grade from what we already have. I want to use everything that was under my hood except the block and heads for the new street car. It was a fresh 416 and I thought I would use it all instead of buying everything again. We have many engines and parts just never had Indy X heads. Sorry for asking or offending those who have them. I think The factory ported X heads will work just fine for me.

View attachment 1716462452

AAR 'cuda, rejetted factory 6bbl, 408" w/a .600" lift cam, 9.5" converter, 1&5/8" headers went 114mph with untouched LA-X's on it. Probably more in it.

 

[Locomotion]

AAR 'cuda, rejetted factory 6bbl, 408" w/a .600" lift cam, 9.5" converter, 1&5/8" headers went 114mph with untouched LA-X's on it. Probably more in it.

360, 750 Holley, .474" cam, 8" converter 1 5/8"-1 3/4" step headers, LA-X with 1.92/1.625 valve job & lite mill, as cast went 117 @ 3,540+ lbs.

But the point I'm trying to make, while the LA-X are good heads, Oldmanmopar has a set of factory 894 X-heads professionally ported by '70's Mopar guru Ed Hamburger. (Probably not max ported.) He is correct if figuring that his ported 894 X heads would likely flow about as much if not more air and not justify spending $1200 on unported LA-X heads. Both as cast - LA-X flows more. Both ported - LA-X flows more. Ported 894 X vs unported LA-X - ported 894 X is probably better and no money spent. If not better, certainly not $1200 worth.

For WIW, something around 240 for as-cast LA-X 1.92/1,625 sticks in my head but I can't find anything in print. I believe OEM 894 X heads were often shown as around very low 200s I also have an old "For 340's & 360's Only" Hamburger catalog which may have details on his ported heads but I hid it too well. In the early '80's when I switched from 2.02 X or J heads to 2.02 W-2 heads, I picked up about 3 tenths. (Minimal smoothing, if any.) But it's been too long to remember the details. As mentioned in my post #5, I picked up at least 2 tenths going from as-cast 587 to as-cast LA-X.

Can't go by flow #'s alone but the examples & estimates are good enough to show the standings and a correct decision.