Really would like to see some flow #'s on both ported and stock LT1/4 intakes and the max RPM range on all if they're any difference.
Plus,I'm trying to figure out is what AFR's I should get? I got extra LT1 intake. So instead of shelling out 2??.00 for the LT4 intake. If porting one of the LT1's I already have and get the LT1 195 AFR's would it be a better route money/performance wise versus a LT4 intake and LT4 AFR's. The rest of the my combo is pretty much figured out except giving the specs for a custom cam.
May be putting too much thought into this but I want to get the most bang for the buck per say.
BTW it'll be a 396LT1/4 motor when done.

 

I've been looking at a similar issue and I think you've answered your own question. The price difference between LT1/LT4 AFR's is minimal, so the only difference is a $250.00 intake for the most part, for a much larger potential air flow and accordingly HP numbers. I really think your better off with the LT4 stuff especially when talking about a 396.

 

So the intakes ports on the LT4 intake are actually larger than the Lt1's and not just raised higher? Or will a ported LT1 intake flow as much. Seems like at some time during the life of the LT1's somebody would have dyno charts and flow graphs between the two ported and unported. Of course they made have and I just don't know how to find the info.

 

From the factory, the LT1 and LT4 intake manifold ports are virtually identical. The key difference is that the LT4 manifold has more metal at the top of the ports, so that they can be ported to match the LT4 heads, or even more critical, extensively ported to match well-ported LT4 heads. But the odd thing is, from the factory the LT4 intake doesn't even match the LT4 heads. They take a lot of work to support well done LT4 heads, but the results can be very worthwhile.

 

That is interesting, but to me more importantly, it is my understanding that LT4 heads have much more potential than LT1 heads, even when comparing AFR LT4 castings to AFR LT1 castings. Which is why it seems to me that adding an additional $250.00 for an LT4 intake to your costs, considering that you've already laid out the rather high dollars for AFR castings, is a no-brainer.

 

I was simply responding to his comments/questions in the immediately preceding post, regarding the LT1 vs LT4 intake. I agree... for maximum performance, LT4 heads are the way to go.... that's what I am running.

 

Sorry Injuneer, I was really looking for verification/validation, as I wasn't sure. I guess I didn't word my post very well.

 

So you haven't bought the heads yet, right? How much are AFR LT4s going for? Scoggin-Dickey (www.sdpc2000.com) has CNC ported LT4 heads for $1025 each complete. They say on their web site that with these heads and a 383, LT4 hot cam, they made over 500HP (at the crank). The HOT CAM is very mild by todays standards, especially in a 383ci. With a custom matched cam you should make close to 500 RWHP. This is the route I wanna take. Build a strong bottom, add a small 150 shot of nitrous, BAM your haul'n azz.

 

That's correct. Haven't purchased the heads yet because I was researching bout the intakes first. Got the used block and a stroker kit but have to decide on what intake to use to be able to chose the heads then supply that info to cam maker to get custom grind cam so everything will work together. Sooo..If somebody could point me in the right direction of the flow on some LT1/4 intakes and max RPM's of each

 

After porting AFR 195s you'll have about the same in it as those LT4 heads.

I am using AFR 190 heads that are simply cleaned up on my 383 with stock ported LT1 intake, AFR told me the initial ports on the 190 and 195s are identical, but there is moor room in the roof of the 195 to match the porting done on a modified LT4 intake.

 

Where's all the tech heads at?

 

For my LT1 396 Build Currently going on I am going with the AFR 227cc's Head with a 2.100" Intake and a 1.600" Exhaust valve size. Competition fully ported, with a fully CNC'd Intake, and someone told me that Lloyd can even get more outta the AFR's, that is once he starts accepting work again...What AFR heads were you lookin at? That might help people route you in a direction...

 

So what I gather is that the LT4 intake doesn't do anything for the RPM range or have any bigger ports it just has raised runners that can be ported more than a stock LT1.
Nobody has ever dyno the difference between the 2 stock vs ported.
Nobody knows if there is a rpm range difference(say for example: idle to 5800 vs 2500-7000rpm).
But it's better to buy LT4 stuff cause of the allowance in removing materail to port match.
AFR195's is the ones I kinda figured would be ideal for a 396 build up

 

loyd is accepting work.

and yes go with the 227 especally on a 396

 

interesting thread.i was wondering about this not to long ago too.i also plan on going with afr fully ported(comp pkg) 195cc lt4 head and getting the lt4 intake manifold.my plans is a blown 355.my only question is,do u have to bring to the machine shop the intake manifold and the heads so they port match the manifold or do u just tell them which head u have and the specs of the head.i would think just porting the lt4 manifold to the max would do the job.