LT 1 to L98

[chevy]

I am going to convert an LT1 intake manifold to fit my L98 engine. I know that I have to provide a hole location fo the dist. and I may have to relocate or remove the EGR valve. I was woundering if there is anyone out there that has allready done this and if someone has any helpful tips. This is going on my 90 Roadster (383) Thanks

 

[Ken]

I believe Chris (69MyWay) has been working on something like this.

 

[Edmond]

He started a thread on it:

http://www.corvetteactioncenter.com/forums/showthread.php?s=&threadid=33127

He also had the website to a guy who can do the thing for you but I forgot it.

 

[69MyWay]

Chevy,

I rarely start something and don't finish it.., but as of now, this project is unfinished.

I am sure you read all about it at the lt1 intake website. That fellow is pretty friendly, and pretty good about writing back to you with questions.

After looking it over, my best guess is to get with somebody that does aluminum welding. That way you can make the mods, first class. You have to watch out to avoid spending as much as you could have just bought a miniram, or super ram before it is all done.

"If" I ever finish this, I will shave the EGR poriton off so that I can put a big distributor there. I will also use a different fuel pressure regulator so that I can move it down off the upper rear rail.

Take plenty of pics for us.

 

[Vettes4Life]

www.lt1intake.com

this is a site who does the conversion
i used to have a 91 Z28 and this was popular with all the TPI camaro folk

IIRC, there was a problem with using the LT1 intake with aluminum L98 heads

better research this

 

[Moonunit 451]

I sent a completed one to Mad-Mic about a month back, he might be able to help you, he hasn't installed it yet so he could get a good look at it. I think he's out of the country for a few weeks though. I didn't do it so not much I can do for ya, never installed it either.

You could go to this webste and contact Chris at the e-mail at the bottom. I bought it from him and I think he may have done the conversion, not sure. Good Luck.

 

[bossvette]

I don't know why you would want to go to all that trouble to modify an LT-1 manifold to fit an l-98 when there are aftermarket manifolds with the same features. The shorter runners raise the torque peak which should be accompanied by a cam change/head work/exhaust . why not swap in the whole lt-1?
Just my opinion, it would be less work.

 

[Edmond]

I don't know why you would want to go to all that trouble to modify an LT-1 manifold to fit an l-98 when there are aftermarket manifolds with the same features. The shorter runners raise the torque peak which should be accompanied by a cam change/head work/exhaust . why not swap in the whole lt-1?
Just my opinion, it would be less work.

Boss,

Converting an LT1 manifold is cheaper. Plus, you can reuse your old rails and injectors. The MiniRam is the same thing as the LT1 manifold but the MR is ~$1,000 while the rails are ~$300. You can probably get an LT1 intake at the junkyard for ~$150 and a couple hundred to do that conversion.

I think doing the conversion is for people who don't mind doing the work and don't have a big budget.

 

[bossvette]

too bad the Holley stealth ram won't fit under your hood, the manifold is around $300 and the fuel rails are not bad I don't remember exactly but I think the whole setup is less then $500 ( baseplate/plenum and fuel rails). that is my next Mod along with a L-88 hood

 

[Edmond]

too bad the Holley stealth ram won't fit under your hood, the manifold is around $300 and the fuel rails are not bad I don't remember exactly but I think the whole setup is less then $500 ( baseplate/plenum and fuel rails). that is my next Mod along with a L-88 hood

I swear that I read something written by Grumpy about a new Stealth Ram that would fit under the hood of our Y bodies. I'll try to find the site and make sure. And yes, it was a cheaper package than either the Mini or Super Ram.

Since the power curve would be shifted up with these mods, what gears would work well? I'm going to guess that he has 2.59's or 3.07's?

 

[bossvette]

its all in what you are going to use the car for, now that I am an Old Fart I use a 3:36/3:55 not to sure but its what came in it. The TKO gives me excellent Acelleration and a reasonable cruise rpm. When I was younger it was 4:11 or 4:56 with a close ratio and the engine singin.
a 3:5 to 1 or near abouts that with a modern 5 or 6 speed OD trans can't be beat for a driver

CLICK for complete info on the 1st CruiseFest in Auburn.

 

[Mad-Mic]

I swear that I read something written by Grumpy about a new Stealth Ram that would fit under the hood of our Y bodies. I'll try to find the site and make sure. And yes, it was a cheaper package than either the Mini or Super Ram.

Since the power curve would be shifted up with these mods, what gears would work well? I'm going to guess that he has 2.59's or 3.07's?

Grumpy advertises a modified plenum setup for the stealth ram. it's angled down to clear our hoods.

i haven't did my swap but after pricing intakes for L98 motors best bang for the buck is a converted LT1 intake. you can get one from www.lt1intake.com fora bout 800+ bucks cheaper if you find someone that is selling one or do it yourself which MoonUnit hookd me up with one i will redyno the car with a few other mods with my stock TPI then swap the LT1 intake on and dyno the car. i get dyno time for 80 an hour so it's cheap enough to see what the difference will be. from my research from 91 to 92 vettes the internal's were very close to being identical with valve size, cam size, valve train and heads except the intakes and the LT1 intake made 60 more hp but lost i think 15 lbs of torque. i'll be optimistic and say a good 30+ extra hp and the 15 lbs of torque loss from stock to stock or midly stock to same mods as the midly stock motor was/is.

the LT1 intake can support upto 7500 rpm for highly modded or race applications and have heard good things about it except some sealing problems on the lower intake to block gasket. use alot of RTV here there are a few other things that needs to be corrected in order to use. need to make a washer shim for the distributor that is raised 1/4" to support a coiless distributor like out of a 87+ FBody. you can get one with coil about 50 bucks in a junk yard.

these are all new prices with fuel rails if memory serves me correctly.
LT1 intake with custom fuel lines 800
Big Mouth LTR intake 900
SR 1000 MR 1300

when i dynoed the car hot and blew the EGR tube out due to rushing the car after a header install the whole time the car was in the torque curve. hp dropped off at 4400 rpm and max torque was 3000 rpm. i'm gonna guess from my research my rpm range will be about 5200 rpm hp drop off and about 3800 rpm on the torque. that means i'll atleast need a 3.23 gear to pull as hard as the 2.59's. due to the rpm band increase. well that won't happen on a gear change unless i find some cheap 3.07's because when i put my short block heads LT1intake and cam in she'll make the HP to pull the 2.59 or 3.07 gear down to the high 11's easily. i'll wait till the D36 breaks and go with a D44 unit with 3.45's which might be soon

 

[90coupe]

There is a Web page LT1Intake.com that provides tons of info and will sell you a modified intake. I emailed to guy and got fast reply. They even have a link to a sight where someone ran a comparison to a miniram...it's about the same. Cheap and looks like easy way to go.

Ron