wolflt1

hi every one,
i need your help.

which intake manifold gaskets should i order for the 1970 lt-1? (between intake and cylinder head)

i checked the different vendor offers but no mention of gaskets for a lt-1.

are there any special things to notice when taking off/reinstalling the intake manifold?

thanks

CheezMoe

I always use Fel-Pro 1206. These should work fine for your LT1, but you might want to wait for an LT1 EXPERT to reply.... Tips:

1. Drain Coolant
2. Have a good way to cap the fuel line when it is removed
4. IMPORTANT: Mark the distrubutor button so you can put it back in the same place. Dont turn the motor over while it is out. If the motor turns or you forget where it was, you must set #1 TDC, set the distributor and then get the oil pump drive lined up. This can be a mojor PIA. Get off a tooth and then timing issues drive you nuts!
3. Clean, clean, clean. Both the manifold and head surfaces must be smooth bare metal before re-assembly. Lay a rag in the lifter valley while cleaning the head surface, and use a shop vac to suck all debris and any spilled coolant.
4. The FelPro set come with cork pieces for the front and rear pads. Most folks pitch them and use RTV instead. I have always used them with some red high-tack sealer. I use the high tack on the head side of the gasket only, just enought to hold it place while setting the intake.

Good luck.

Solid LT1

Trying to be helpful is nice, giving out bad information maybe not so nice

The Winters Foundry LT-1 Z/28 Holley intake has no flange at the cylinder head to intake mounting point, it leaves little room for error in chosing and getting the right gaskets. You are limited to Fel Pro #1256 which has opening for the intake heat crossover and will allow choke operation, the #1204 "race series" stock port size gasket which will have to be modified to allow OEM choke operation or if you want prefection the just like Detriot Gasket Company made for GM back in the day.....Paragon Corvette intake gasket Link: https://www.paragoncorvette.com/p-35...-kit-w350.aspx

TedH

Stock port dimensions with heat crossover Fel-Pro 1256
Same port size and thickness as Stock but with blocked crossover: Fel-Pro 1204

Stock port: 1.23" x 1.99"
Thickness: .060"

CheezMoe

I stated "should" on the part number ...1206 has a bigger port than the 1204...edited for clarity..what other information was bad....??? You holier than though trolls are quite detrimental to ones desire to try and be helpful or respond to anything on this board!

63split63

I don't like the look of the blue gaskets . I use Victor .

Bill

Solid LT1

DUDE! I tried to put it a civilly as I possibly could in my post. Looking at your Avitar I see a rubber bumber Vette....does it have a LT-1 in it? I have owned more than a dozen 302 Z/28's LT-1 Corvettes since 1977 and have built quite a few of these motors over the years. You pipped in with "slap a Fel Pro #1206 on it" that is FLAT EFFING WRONG BAD information that, HAD the poster who inquired about the CORRECT gasket put your offered up Fel Pro#1206 gassket on, he would have most likely encountered MASSIVE vacuum leaks out the top of the intake runners, if he has a factory LT-1 choke, the thermostat will never heat up properly and may even draw oil from the valley area under the intake manifold, THAT IS HOW BAD the iformation is that you gave the poster. As far as the rest of your information, I don't find the need to gunk up an engineered gasket with additional sealer, I will sometimes use sealant around the water openings, but don't often use it around intake ports as fuel and component shifting during heat cycling can cause a fully glued on gasket to fail much quicker than on installed dry. Sometime take a good look at a modern intake manifold gasket, the have coatings on them to allow displacement and movement of mating parts, if you GUNK UP that coating with sticky sealer your defeating the purpose of much expensive engineering and years of development by modern gasket makers. On the motor end rails (or China Walls ) I use Permatex The Right Stuff as I have found it to be far superior to Silcone sealant in my builds.

Good thing about this forum, after you edited your original reply to make yourself not look as bad as you originally did, the Forum leaves a record of such editing of original posts. Like I said, its NICE to try to help out BUT!, NO SO NICE to give bad information out to people seeking to do the job correctly and trying to only do the job once. As far as your disributor information, I turn the motor over until the rotor tip is pointing to a good refrence point like the power brake fitting, then shoot a quick photo of the rotor location in my phone for future refrence. The base of any early C3 era Chevy intake and distributor is marked at the factory with a chisel mark when correct timing is set on the assembly line, now if the Vette has a swapped out distributor or intake swap, that won't probably work but, I take a clue from Chevy and mark my motor builds just like they did, after getting timing correctly set and motor broken in, I re-chisel that mark (really can upset some guys especially 302 Camaro guys until I point out the factory did it too ) The refrence chisel mark will give you the best refrence for setting timing before refiring the motor.

To let you know what kind of guy I am, years ago a good friend just had to have a 302 Z/28 after riding in mine, we looked for weeks in the local paper (way before Ebay or Craigslist) and had looked at this one 69 that was pretty nice but, Dusk Blue in color, I noticed it didn't have much bottom end, stumbled badly and backfired many times on start up and I wondered if some idiot had put a #140 "Off Road" cam into it because it ran so badly but, I also saw it had the stupid Mr Gasket stack of carb gaskets with aluminum seperator plates proported to "cool the carb for increased HP". MY buddy finnally decided that Z was the one, we went to the guys house, offered him $500 less than asking price $2750 in real dead presidents, the deal was struck, I whipped out my tool box, ripped the carb off, swapped out the carb studs, installed a good quality carb gasket, retimed the ignition and lit off a well running purring like a kitten 302 motor. I told my buddy to give him a extra $20 for pizza and beers.

Thats the kind of guy I am.......your the one who elicted this response out of me, not too nice to call someone a troll who has probably FORGOTTEN more about 302/LT-1 Chevys than you will ever know

OH! one last correction of BAD INFO on you edit the term is "Holier than Thou" try to at least get something this basic down right

Solid LT1

I AGREE 100% with you! look at my post, if you want the RIGHT ONE support Paragon Corvette in their efforts to provide the correct gasket. I don't like blue gaskets peeking out from the intake so much that I waste my time and either cut and remove the offending gasket material (not an easy job) or get the right one from Paragon. Cometic used to have a great graphite impregnated gasket but, it is long been discontinued.

CheezMoe

Wow! My apologies for upsetting you so much. You are absolutley right, how ignornant of me to have thought other wise! Why do I get the feeling Im conversing with my wife.


Right again. I totally forgot they had heat x'overs and small intake ports! My bad! But I never said anything about gunking anything up with sealer...but of course your method is the "perfect" method so I hereby refer the OP to you! Peace!