Can the ports be matched? Has, or is anyone in the process of doing this swap? On johns site it states that he prefers to stay away from converting LT4 manifolds and that he has only heard of it working. I am building a 350 for the vert. with a xe268 cam and would like to go this route, but have never personaly seen a LT4 manifold. Would comparing just the gaskets be a good enough way to see if they are close enough to be port matched?

 

You can buy a new bare GM RAM-JET intake manifold now.

Cost will be about the same as converting a LT-4 intake.
Less hassle.

 

I don't know you can get a new LT4 manifold for $230 through summit. Use the same throttle body, throttle-trans-cruise cables and bracket assembly.

 

yes but you'll then have to $modify$ or pay to have it modified
and then buy the supporting parts, throttle body, fuel rails,
cables brackets etc etc.

Overall the final cost will be the same or cheaper to go with the RamJet. It's great manifold with loads of horsepower potential.

Not saying you can't do it or get good results, just that the
$bottom line$ will end up about the same.
The initial cost of the bare manifold is only part of the picture.

 

Yes. Get an intake gasket for an LT4 head. Notice how much higher the port location and casting is for the LT4. If you can match the ports at all, you may only end up with a pencil-width of gasket flange left above the ports on the Vortec heads.

You'd probably be better off porting (and raising the ports) on an LT1 intake, or going aftermarket as suggested.

 

hey all...

I've been pondering this myself ... I got the idea from SteveL981991 (??) he is local to Atlanta area . He put a LT4 intake on Fastburn heads .. same ports as Vortec ... I've emailed him a couple of times about it but haven't heard back

Vader ... have you actually held the gaskets together ??
I'm about to order LT-4's to do just than !! I've found a good deal on an intake and want to jump on it ....

Since I'm REALLY gulten for punishment .. I'm putting a LS-1 computer and harness on my pig , so converting the LT-4 for a distrib isn't an issue !! I'm droping the motor in either a 1st gen or a 4th gen .. so distribs CAN'T happen !!!


RAMJET is about $400 from chevy
then you NEED fuel rails ..nothing used fits ?? new only ??
Throttle body .. nothing used fits ?? new only ??

LT-4 $200
TB USED $50
fuel rails USED $100

LT-4 looks to be WAY CHEAPER than RAMJET , for me

TVP

 

I was under the impression that lt4 and vortecs had similer ports as far as how much they were raised. I guess this is not the case, that was the only reason it looked like an appealing combo to me. The ram-jet is a nice piece but after you add up all the parts for it and go through the effort to get your cruise-trottle and trottle pressure valve cables to work on the opposite side of the throttle body it seems too costly. I wish holley would make a stealth ram for vortec heads.

 

Just FYI, the vortec/fastburn heads are based identicle to the LT-4 casting, only the reverse cooling design was changed on the vortecs/fast-burns back to regular cooling flow pattern. Yes, the LT-4 intake will work on vortec heads with a little modding of the intake.

However, I would still suggest using the TPIS mini-ram III if you can swing the $$$$. This would eliminate the remote thermostat that you will have to run with the LT-1/LT-4 (which is kinda ugly IMO).

Just my $.02

 

Yeah I don't like the remote thermo housing thing either, but I think its the lesser of two evils vs a $1000 intake. If they are the same ports then they should match up like factory. Is this for sure the case? I guess I could go ahead and order the intake and compare it to a set of gaskets for a 96 truck. I think summit would take it back if it would'nt work.

 

Yea it should work if you go with the Milican conversion.

OR, you could wait a little and campaign with the rest of us and see if Holley will make us a Stealth-ram base for vortec heads!