441LSXTT

Is there any really good dyno comparison between the two intakes ? Was the MSD ported? Did you have the Hiram ported? I am considering on waiting to see how this new fast Hiram works because they claim 30 more than the standard holly Hiram. . Basically I have a 468ci LS7 that makes 680rwhp around 5700-6000RPM with a ported MSD. It chokes it bad up top. Cam should peak around 7000 especially being over a 740 lift with over 270 duration. With another 800-1000RPM It should put me around 720+rwhp.
Any help or any feedback would be appreciated if you could post up in the graphs if anybody has them. Thank you for anyone’s help

MickVette

I was considering the 468 before things to a turn in a slightly different direction. I was considering this:
https://speedmaster79.com/chevy-gm-l...-system-satin/
..and was going to build an air filter system for it.

ls404fd

50mm throttle bores would choke a 468 pretty bad. You really need something 60mm+.

For reference, intake valve size is ~57mm.

I thought there was some msd vs hi ram dynos floating around this site?

HPR and GSpeed just had a Hiram on a 468 on the chassis dyno didn’t they?

MickVette

Missed the 50mm part....

I think they had the 468/hiram combo installed on a track car somewhere here. I remember someone mentioning that might be an issue while making right handers.

jayyyw

I don't have any true back to back info. I did make more power with a hi ram and a little smaller cam than I did with a Mamo MSD and a little bigger cam. Also peaked 500rpm higher. Trapped higher. Ran better.
Msd - cam 248/260 111+3 .660
Hi Ram - cam 243/258 114+3 .660

Silver Bullet C6

OP have you considered shortening the runner lengths of the MSD? Also, was your air filter new or recently cleaned? I know on my FI car, a clean filter helps

ls404fd

That is a wayyyyyy smaller cam. Impressive to be peaking 500 rpm higher with 5* less intake duration and the same IVC.

Was the 248/260 cam just too much trouble on the street?

jayyyw

It didn't perform as I had hoped and I thought was causing issues with my valvetrain. That's why I decided to swap it out.

Jayfabs

I wonder at times how my car would do with a high ram. I went from a 244/258 114+3 to a 247/261 114+4. I do have an extra hood but cutting the cowl eh. I’m interested in this new fast intake

441LSXTT

im really wanting to wait for the FAST!! My cam now is 263/275...741/741...112+3. It needs to breathe

Jayfabs

yeah that’s decent size cam! I’m really looking forward to some numbers from u. What rockers do u have again?

Jjagg0125

Ok not to hijack but what is this new fast intake being talked about and is there a rough eta? Any info on it at all yet?

441LSXTT

It is the FAST version of the holly Hi-ram. And it actually has three different interchangeable runners for a proper length for your combination. What’s cool is the longer runners actually face forward which means it’s scoops to air

jayyyw

I think you'd pick up a good amount of power without sacrificing much, if any, in the mid-range. You'll have to cut the cowl with either intake, might as well do it now.

FNBADAZ06

We're hoping to see a pre-production model by the end of next week, but, as always this has been a moving target.
We were hoping to have had it in late January but they had to make some manufacturing changes (is what we were told).

Da Z06

Send me your MSD and I will modify it for you. Pay shipping to and from and my cost of materials and I will do it free of labor.

PM me if interested.

Da Z06

This.

FNBADAZ06

That is very generous
I wonder if the MSD runners are available in a rebuild kit ?

Da Z06

They are not. The modified MSD will not require a modification to the hood or firewall. It may just get you the magical 700+ you are looking for.

Jayfabs

how much are u cutting?