can lt4 heads be used with an lt1 intake?

are there any carb intake that will work with lt4 heads?

 

They will work with the LT1 intake, but the LT4 headers are reverse flow coolant so they wont bolt on to a gen 1 block.

 

The LT1/4 heads won't fit the Gen-I cylindcr case, unless you make a couple of small modifications to a cooling passage in the heads. I have instructions and diagrams. All teh bolt holes, chambers, drainbacks, etceter will line up just righ. the LT1/4 heads have a couple extra cooling passages that need to be altered and blocked/pligged. It's certainly worth the little extra preparation for all the extra flow. LT4 heads in completely stock form have been SuperFlow bench tested to flow more than ANY aftermarket SBC head except Pro Topline, Air Flow Research 190s & 210s, and Canfield heads. The LT4 heads with only 2.00/1.55" valves flow better than:

Edelbrock Performer;
World S/R Torquer;
GM LT1 Aluminum;
Holley Systemax;
GM Vortec;
Brodix 8 Pro;
TFS Twisted Wedge (Tie - same flows);
World Products Torquer;
Edelbrock Victor, Jr.;
GM LS1;
Brodix Track 1;
Dart Conquest;
Dart Iron Eagle

I've got the links and data sheets if you need them. Better yet, with a little valve face and bowl increase, pocket porting, and a little port matching work, they'll kick-ash on most aftermarket heads and STILL provide better low- and mid-range torque and fuel economy.

The LT4 heads will accept the LT1 intake, but will require a little machining of th eintake runners to get a good port mathc. The LT4 intake ports are slightly more than 0.100" higher in the castings than the LT1 design. If you can make them work, I think you'll be very satisfied.

 

i for got to mention this will be on a 95 lt1 block
(edit)..but the lt4 heads can be used on a non lt1 block with small mods to the cooling passages then..like a 400?

im leaning towards the hot cam for the FI setup
and i havent decided yet for a carb setup
im open to suggestions

i have a complete lt1 intake (injectors all sensors, fuel rails, fpr) so what pound injectors should i use?...would using an lt4 intake be of any gains to a ported lt1 intake?
will this run WELL on a 730 ecm? or should i change the entire harness over to the optispark?

also are there any carb intakes that will work with lt4 heads?
(FI=$$$$$$)

thanks for the replies!!!

 

The LT4 intake MUST be used when used with LT4 heads. LT4 heads are a raised runner version of the LT1 heads and using a LT1 intake on LT4 heads will cause a big loss in power. There isnt a carb intake for the LT4 heads , just the LT1 heads.

 

Although the LT4 intake is designed to fit the heads, and had a better injector positioning and spray angle, the LT1 intake upper flange has adequate material to raise the upper port opening to fit LT4 heads. The flange gets "interestingly" narrow, but will seal. I raised the port roofs and openings on LT1 heads and matched the intake to fit. The ports ended up at 197cc fom the 173cc starting point.

 

lt1 injectors and fuel rails will fit an lt4 intake right?...

i found an lt4 intake on ebay last night with fully ported lt1 heads cut to fit the intake

what should i do?...i can get an lt1 intake with everything (rails and injectors) for cheap...

there are lt4 heads for sale by themsleves

or there is a lt4 intake with cut to match ported lt1 heads..hes also got a lt4 hotcam

how much more will fully worked lt1 heads flow to lt4 heads?

i was thinkin about buyin all 3 autions (the lt4 heads, the lt1 intake w/everythig, lt4 intake will prepped lt1 heads and hotcam)

then taking the injectors and fuel rails off the lt1 intake putin them on the lt4..and using the lt4 heads..and sellin the worked lt1 heads..
this will goin on either a 406 or a 95 lt1 motor
what do u guys think?

 

The LT4 heads and intake would probably be the better choice. "Fully ported" LT1 heads with 2.02/1.60 valves flow about as well as stock LT4 heads with 2.00/1.55 valves. The LT4 heads will already have better springs, titanium retainers, and 1.6:1 rockers. If you want, you can clean up the LT4 heads to flow better than any aftermarket head except Canfield.

 

If you dont have the LT4 heads already, I would suggest that you just port the LT1 heads. There is a guy, Nighttrain, that will port those heads and get better then stock LT4 flow#s for less then what the heads cost. He charges about $500 for a really good port work. I still dont like running a LT1 intake on Lt4 heads. Its not a matter of if you can port the top of the intake runner to match the top of the head runner, it is that the bottom on the intake runner, when air is coming down it, will slam into the bottom of the runner on the head, and that will cause a lose of hp. The LT4 intake is only about $225 from Pace Parts and if your set on LT4 heads, and dont have them, I would suggest getting some bare AFR 195LT4 heads and haveing them worked over, but you can do a lot more with the LT1 heads then most people think.

 

Oh, yeah. You certainly can. Especially the iron ones:



They finished up at 197cc.

 

well i dont have the lt4 heads yet...but im tryin for them,
i can always get lt1 heads if i dont get the lt4's

if i dont get them theres another auction with the worked lt1's and an lt4 intake..

one question were do the parts have to be machined when usein the following combos..

lt4 heads lt1 intake
lt1 heads lt4 intake

 

I would go with the LT1 heads and intake combo. The LT4 intake will need full porting work to get good #s out of it. The LT1 intake is a better production finished intake then the LT4 is. Now that I think about if you want to get more then the LT1 heads can produce then I would suggest the bare 190 AFR heads ported by someone else and an LT1 intake. The LT1 intake can support well over 500hp in stock form, but the LT4 intake will need some work. Talk to Phil at AI and will agree with me on the intake part. He get some great #s out of LT1 heads and also on dyno#s.

Vader to let you know a good stock ported LT1 head will not only out flow a stock LT4 head, but will come with better valvetrain.

 

today i was lookin through the pace performance catalog and i found an intake for lt4 heads and a carb!!

gen II design only
Ports raised .0100" higher then lt1 ports
holly or Q-jet carbs
$255

i am plaiing on going FI thats why i bought an lt4 hot cam..but i have to change my plane a little to save some cash so im goin carb for now..

what carb should i use?..i was thinking about a holley 750 4160
vacuum secondaries and electric choke..
what do i need to do about my intank fuel pump...
are lt1 block machined for a mechanical fuel pump? and is there anything i need to do on that part..

i know the hot cam isnt made for carbs but like i said i will be goin fi..im sure itll run but how well?....

the casting number on this block is 10125327
10125327...350...92-up...2 or 4...Gen.II LT-1, reverse flow cooling
10125327...350...96-up...2 or 4...Gen.II LT-4, reverse flow cooling

what distributor should i use?...

i know i asked a lot but ive been tryin to get my ride back on the road for 3 months and im almost there...its the home stretch

thanks
Rob

 

Description

You are bidding on a set of GM LT4 Reverse Cooled ALuminum Cylinder Heads for 93-97 LT1 style engines found in Camaros, Firebirds, Trans Ams, and Corvettes. They are GM casting number 12555690. These were the optional heads that could be ordered on the 1996 Corvettes as a kit. These heads were GM blemishes that I aquired and totally rebuilt. They have never been run on an engine. They are basically brand new heads that had some scratches and a few nicks on them. One head had a pinhole in it that was repaired with an aluminum tig weld by the exhaust ports on the exterior of the head. Mechanically they are perfect. My modifications include: Manley Performance Stainless Steel 2.02/1.60 valves, Manley Performance Steel Retainers, K-Line Bronze Guide Liners, Positive Valve Stem Seals, and Pioneer Performance 1.250 valve springs. They have had a light cut on the head mating surface. They have 54cc combustion chambers. The spring pressure is 120 lbs on seat and 300 lbs @ .500 lift. The springs are good up to .540 lift. They are machined for either screw in studs with a self aligning rocker or screw in studs and guideplates with non-self aligning rockers. Note: using these heads will require the use of an LT4 lower intake manifold which is available through GM Performance Parts. These heads are sold as is. Thanks for looking and good luck bidding. Email me with any questions.


right now there goin for $620
how much more are they worth

fomr what ive heard there about the best head out there

 

vader, can u send me those flow charts that u have?

thanks

 

You've got mail...

 

wow they flow really well....i was surprised to see the E/I ratio of the l98 heads compared to the rest of them,, bas good or better then most heads up there...they just dont flow


right now the bid for the lt4 heads are at 820
id really like to think that these heads are worth it..especially after lookin at the flow numbers...

thanks again guys!!! keep the replies coming

4 hours and 24 minutes till i win or loose them

 

Right now I would say save your money and have Mindgame on cz28.com port some LT1 heads. They will flow more then LT4s, about 270/200 at peak, and will cost about as much as those LT4 heads. Plus to make any real power you'll need that LT4 intake ported, unlike the LT1 intake. Ported LT1s cost less then LT4s and flow more is then what that acution is at right now.