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247malibu
04-18-2011, 08:09 PM
Just curious if anyone has used the LT1 exhaust manifolds that go over the top instead of the log type or ram horn type ? What do you think of them if you have tried them ?

hrdchrgin13
04-18-2011, 10:05 PM
I always thought that the late 80's camaro manifold's would work good.

dirty white boy
04-19-2011, 02:39 AM
mid 90s truck manifolds are best pick....

247malibu
04-22-2011, 04:32 PM
Let me ask this, how would manifolds against headers workout ? I just cant get headers to fit on the metric car. We cant run the over the frame headers they have to go underneath. I'll have to buy a set that fit the ones I have either hit the crossmember, lower a frame mount or my slave cylinder off the bell housing. Im almost ready to go now. I could run manifolds or sit out a few weeks & buy some headers. So,, if I run manifolds ,how much diffrence will the cars with headers be over me ?

hrdchrgin13
04-22-2011, 05:20 PM
You could possibly run the manifolds just to shake the car down and all, but your robbing yourself of horsepower by not running headers. I think like 10-25 hp. I would personally buy the headers and run them.

LowTechRacing
04-22-2011, 05:59 PM
I would buy some used ones off of craigslist and cut them up to make them fit. The only other thing you could do is find ram horn exhaust manifolds. Make as goo of power as most headers.

dirty white boy
04-22-2011, 06:43 PM
i had a set of hooker headers on a stock monte carloSS,..not alot of room but thay fet good,..your motor set back or setting low??? manifolds will be 25 hp short,..some clam even more,..be worse the higher rpm you turn...

Moldymulldoon
04-22-2011, 09:14 PM
Can you run the shorty header? Granted it isnt as long as the street stock headers BUT they make them in 1-3/4 primaries. NOT the block hugger style. You can change the starter and the oil filter with out alot of hastle.

I have a pair of the 2-1/2 center dump manifolds with porting. One ear is broke on flange but should be no problem to fix. Willing to sell if interested. Let me know.

Moldy

jasonmischke
04-22-2011, 10:22 PM
Running cast exhaust, any type(ram horn,lt1,truck etc) will cause significant power loss on an open motor. They also will add heat to your engine. A good set of headers will increase your top end HP anywhere between 5%-15% depending on your cam profile,engine stroke and valve size. You will also see a 15-30 degree temperature decrease in your motor with headers.

Schoenfeld offers a good metric header, provided you have not moved the motor back more than 2 1/2 inches, if so you would have to dent the firewall where they touch it.

I am set back to #1/even with ball joint and I run the 1 3/4 tube 3 1/2 collector headers. No problems and they only cost $159 @ L&M Performance..shipping is extra

247malibu
04-22-2011, 10:45 PM
Ok, I will get it going but in the market for headers. I have 2 diffrent sets of the shorty headers & 1 hits the lower a frame mount on DS. The other fit ok ,they angled back more .I did have to ding the #1 tube for a motor mount ,just a tad. But I have the gold bellhousing with the dual starter type,( sucks ) but I cut the DS hump as much as I could so I could mount Flat bar on the side of the B.Housing for the slave cylinder & it hit. Centerdump manifolds or ramhorns would work but i would have to notch the crossmember a little. The angle rams work good but I only have 1.And its the Pass Side.
I'll just run the manifolds I have & order the Schoenfelds,but I will have to have a set that fits the clutch fork . My motor is only scooted back a little,cause I didnt want to notch the frame for the fuel pump. It use to be illegal but now they've just about let you run whatever.
I appreciate the input. I figured they would wear me out without headers,but im sinking every dime buying little junk. But headers are next, Thanks again.

Dirtman29
04-22-2011, 11:30 PM
I got the schoenfeld 186-3 (under car) headers on my metric car, the pass. side is a pain to install but it will go on, I slid the motor to the left, bolted it on & slid the motor back, made it easier.