There is a company that modifies HSR intakes for L98's. I read on the other forums that they are going to start making them for the LT1 soon. Is anyone running a converted HSR on their LT1? Details? This could be a great alternative to the Edelbrock Air Gap or sheet metal intakes.

 

An HSR intake is.... ???

 

Holley Stealth Ram....

http://www.stealthram.com

 

I found some pics of the rough intake they are testing/designing for the LT1 f-body. They are building it to fit under the hood without loosing too much in the runners or velocity.

 

gonna be costly in comparison... but we'll see. Best of luck to them regardless, as there aren't enough options for the overlooked LTx platform

 

Its the same place that came out with the HSRs for the L98s, USM.

 

AFR needs to just design a 15 degree head for the LTX and someone needs to come up with a manifold to match the angle.

 

I believe so. I found the thread on LS1tech.

 

except for the distributor hole (fill it, cap it, slap it), the intake should just bolt on !?!

After looking at LT1/4 heads to convert to Gen I type, I can't imagine that the reverse could be too bad?

Lastly, the lt1 is quite the high flow intake. Why would you LT1 guys want more of a tuned RPM (IMhO still 6+)?

Just a little Q's to brighten your suzzie

 

no, the intake bolt hole locations are different.

You'll also have unused cooling passages, but that should be OK.

Are you looking for more torque?

 

The LT1 intake does not flow all that great. Yes it has shorter runners for high rpm hp, but it doesn't have much of a plenum. A stock LT1 intake will flow 245-250cfm. Ported I think its around 270cfm. There are a good amount of LT1s that have ported stockers(heads) or aftermarket heads flowing in the 290-310cfm range. The lt1 intake cant get the full amount of air to them. If your intake flows 270, your 300cfm heads will only see 270.

Most lt1 guys that have high flowing heads will go to a single plain. But I saw a dyno comparison between a sp and a HSR. The HSR had 20rwhp on the sp at 6600rpm. The lt1 intake ported, will flow well past 7200rpm. Not many people spin that far up. There have been tests with sheet metal intakes with the same size runners as the HSR on LT1s. The sheet metal intakes provided over 40rwtq at 3600rpm over the ported stocker and about 25rwhp to 6500rpm.This is on H/C lt1s. When you gut the stocker out you lose a good amount of low-mid range torque. Not to mention the rpm you have to turn to get the intakes full flow potential.

 

It depends on which single plane they use to do the LTX conversion.

Most people are using the Victor Jr or the old Victor E....

Light years behind the new 2925 Super Victor (which I have) or a Brodix HV. My personal LTX breaks the 400ftlbs (rear wheel)@only 3400RPM and carrys over 400ftlbs to 6500RPM. I have over 300ftlbs as low as 2400RPM. Keep in mind my cam is well over 240@.050 and .625 lift with 210 AFR Eliminators on a 383. With a 6spd I could really care less what it does below 3000RPM... but just to play devils advocate, it'd still be plently strong if I had an auto and a common 10" converter.

As for porting the stock LTX intake... it's all about cross sectional taper in the port. You can screw one up in a hurry if you port those short little intake runners straight...
Will

 

The single plain was a Holley.Here's the link:
http://www.eecis.udel.edu/~davis/z28...age031229.html

 

Id read a few times the stock LT1 intake only went 220, is there a link where we could see some hard info to know for sure?

 

I called a shop out in Cali. that has a flow bench(my friend delivers mail to them) and asked them if they knew flow #s on a lt1 intake. They told me stock the runners flow between 245-250(I've also heard 220). Most of the ported versions are around 270cfm. They told me the one thing that kills the intake, in their opinion, was the small plenum.

They seemed to really like the HSR. The guy told me they were getting,in some cases, over 300cfm on some ported models. I've looked for links as well for some more proof but flow data on intake manifolds are few and far between. Everybody's usually too concerned on what their heads flow, ignoring that they'll only flow what their intakes allow them to.

 

Can you post a few pictures of your conversion?? I'm looking for a better manifold than the ported LT4 I have. Could your setup be something for me??

 

my 383 had a cam that didnt really favor low end torque but my torque curve was very flat. I had a lot of duration spread on my cam which bleeds off the low end alot.

I still had over 360lb ft from like 3000 to 5400 rpm. Peak of 380. This was on a HOT day and on my final pulls (10 total that day) Engine was HOT. Torque dropped each run but last run made 371wtq. I'm sure its 380's cool. And I bet its well over 340 at 2000-3000. HSR has a FLAT curve

proper cam i'd surely break near 400lb ft and average 375-380

 

No Problem on the pics. Its a converted 2925 Super Victor with a sheetmetal upper/TB adapter. Orginally done for me by Jeb Burnett.









As for, if it's for you or not. I can't really say. It's a lot of work and money. If you don't have a 600+HP motor, I'd say it's a waste of money. Also if you have that kind of power the SP conversion is kinda tricky to drive. Once it comes up -the TQ curve is flat as a pancake... only problem is the TQ comes on in a hurry... mine gains over 100RWTQ in just 1000RPM....

I'd like to add that the 2925 lower intake on mine has no port work done to it what-so-ever. Thats because me working on refining the intake manifold package has been side lined while I sorted out other problems with the motor.

As cast the 2925 is now well known as having a plenumum problem (on the top radius to the intake runners) that needs a lot of port work to correct. My sheetmetal upper intake/TB adapter only exaragerates them.

When I started the conversion the 2925 was Eldebrock's latest and greatest 23 degree intake and no one knew about the plenumum air flow problems... by the time I was done with everything, we knew it would hurt me but I chose to try it as cast first to get some bugs worked out in the motor. It is still putting down good HP and the TQ curve is exellant. I don't have my latest dyno sheets uploaded yet. The car has been getting dyno'd quite a bit lately as I chased down some valve train problems, which it seems I have finally solved (it went from a disapointing 440RWHP to a respectable 478RWHP -with more to come).

Now I have some time to refine the intake manifold package. I have a new AS&M Mono Blade throttle body I'm going to test next month and after that I'm pulling the intake off it and send it off to get the plenmum properly modified.

Correcting the plenmum is worth anywhere between 25HP (on a 450HP 355) to 60HP (on a 700HP 434) on a 2925. My motor properly sorted is just over the 600HP mark so the gain should be some where in the middle of that. Judging from my current RWHP, if it gains 30HP it'll be right where it was when we dyno'd the motor with a different SP intake and AED 850HO.

Honestly if I had it to do again, I'd pick a different intake to start with. Probally one of the Brodix's HVH's with a 4500 (Holley Dominator) flange.
Will

 

Will, thanks for the pictures, looking forward to your dyno sheets!!
I think a lot of people on this forum know Denny McLain, well, he had a sheet metal SP also made from Jeb Burnett, and his manifold didn't make any additional HP just TQ. His manifold really looks good and he has been chasing 600 HP for many years, trying everything out including a mono blade TB. Best so far was 483 RWHP.
BTW, haven't heard of anyone on the forum making NA 600HP with a 383 or 396.
Can't find a Brodix HVH manifold on their site. Do you have a link.

Arnold

 

The Brodix intakes I'm talking about are P/N's HV 1000 (4150 flange) or HV 1002 (4500 Flange).

http://www.brodix.com/manifolds/sbmanifolds.html


We'll see what my car gains from the TB are next month. Then after that we'll see what the numbers are with a fully ported intake manifold.

Honestly if I can't break 500RWHP after the intake manifold -I'm going to take it back apart, change the camshaft and bump the SCR.
Will