Lt1 Intake + LTs + Cam
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Burning Brakes
Joined: Aug 2007
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From: salinas ca
Lt1 Intake + LTs + Cam
Hey guys, i was thinking of getting an LT1 intake and cam for my 89 auto with 2.59's. Right now it has LT's to true duals with magnaflows. If i go with the Lt1 i was thinking a mild 224/226 duration, .500 lift max cam. What kind of numbers would i expect to see with a PCM4less tune? Anywhere near 300rwhp/tq?
Last edited by 1989vette; Aug 13, 2008 at 03:17 AM.
Team Owner
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From: Athens AL
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The cam and intake are better suited to a manual transmission. If you want to put this combo on an automatic, you will want a higher stall TC and lower rear gear.
With stock '113 heads, I think you'll make around 300-310rwhp.
With stock '113 heads, I think you'll make around 300-310rwhp.
Thread Starter
Burning Brakes
Joined: Aug 2007
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From: salinas ca
Thanks for the reply vader, yeah i agree a high stall is coming also hopefully a 2000-2200 from PeteK but i need to talk to him about some tranny work. If its better suited to a manual what would be suited for the auto? Stick with the tpi, poke a bigger cam and have the tpi ported with a hi flow base and siamesed runners?
Team Owner
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From: Athens AL
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Well those parts would warrant a higher stall, like 2400-2600.
TPI/SuperRam are better suited for automatics than the LT1/MR, in my opinion. So yes, porting with larger base/runners .
TPI/SuperRam are better suited for automatics than the LT1/MR, in my opinion. So yes, porting with larger base/runners .
Thread Starter
Burning Brakes
Joined: Aug 2007
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From: salinas ca
Thanks vader, what kind of power would that produce? And could i get by with a 2200 stall with a ported/larger runners? What kind of cam would the TPI setup warrent, a LT4 hotcam?
Pro
Joined: Jan 2008
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From: Near Lockport NY Black 1986 Coupe
The LT4 hotcam may be too big for your application unless you do a full port job, including the heads, intake, runners, and plenum. If you mean the hi-flo runners and base intake from edelbrock, don't expect a huge increase in power. They only flow marginally better than stock unless you port the hell out of them. You would be better off with a SR and aftermarket heads.
Also, if you want to run a bigger cam, you need atleast a 2400-2600 stall converter to really feel it. Any aftermarket cam, unless its duration is tiny, will make power over 2k RPM. The hotcam kit is meant to spin over 5k, which is where the powerband of the stock L98 drops off from flow loss - not good if you're sticking to TPI. It would work fine with an SR or LT1 intake.
You basically have two options here:
1) Stick with the TPI and port the hell out of it, get a 2400 stall converter, a mild cam under .500 lift, and 3.07s in the rear. You'll make more torque than horsepower, but that's good for a motor that redlines at 5k.
2) Go with a SR or LT1 intake, port the heads or get aftermarket, 2500+ stall converter, hotcam and 1.6 rockers, and 3.45s in the rear. You'll be able to spin to 6k and have plenty of power in the whole powerband.
Also, if you want to run a bigger cam, you need atleast a 2400-2600 stall converter to really feel it. Any aftermarket cam, unless its duration is tiny, will make power over 2k RPM. The hotcam kit is meant to spin over 5k, which is where the powerband of the stock L98 drops off from flow loss - not good if you're sticking to TPI. It would work fine with an SR or LT1 intake.
You basically have two options here:
1) Stick with the TPI and port the hell out of it, get a 2400 stall converter, a mild cam under .500 lift, and 3.07s in the rear. You'll make more torque than horsepower, but that's good for a motor that redlines at 5k.
2) Go with a SR or LT1 intake, port the heads or get aftermarket, 2500+ stall converter, hotcam and 1.6 rockers, and 3.45s in the rear. You'll be able to spin to 6k and have plenty of power in the whole powerband.
Team Owner
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From: Athens AL
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If you want 2000-2200, its better for any TPI-style or SR setup. You want LT1, then you go bigger.
TPI cam choices depend on what power you want to make.
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Burning Brakes
Joined: Aug 2007
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From: salinas ca
If i were to go this route, how about a set of vortec heads? I can get the hi flow base from SDPARTS and buy a set of large runners and port the plenum or make a sheet metal plenum aswell...It would end up being a tq monster, but would it be in the 350rwtq range?
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Team Owner
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From: Athens AL
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There is no need for Vortec heads. Your stock heads are good enough for about 350chp unported. Just port your heads if you want more.
Pro
Joined: Jan 2008
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From: Near Lockport NY Black 1986 Coupe
I can guarantee that with your stock heads as is, ported intake, and with a cam like COMP Cams CL12-242-2, you'll make roughly 30-40 more chp and about the same torque. If you port the heads, you can add another 10-20rwhp. This cam will make the torque peak rise ~1k RPM, but the beauty of a 2400+ converter will make you launch roughly within 500 RPM of that peak. And with any mods, you need to get rid of those 2.59s for a set of 3.07s.
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Burning Brakes
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From: salinas ca
What kind of power are you looking for, exactly? A strong stock L98 puts out between 270-300rwtq. If you're going down the porting road, I'd suggest using the stock plenum and aftermarket runners & intake for the most porting meat possible. It isn't always about how "big" the area is for air to flow in, it's how smooth the air flows within it.
I can guarantee that with your stock heads as is, ported intake, and with a cam like COMP Cams CL12-242-2, you'll make roughly 30-40 more chp and about the same torque. If you port the heads, you can add another 10-20rwhp. This cam will make the torque peak rise ~1k RPM, but the beauty of a 2400+ converter will make you launch roughly within 500 RPM of that peak. And with any mods, you need to get rid of those 2.59s for a set of 3.07s.
I can guarantee that with your stock heads as is, ported intake, and with a cam like COMP Cams CL12-242-2, you'll make roughly 30-40 more chp and about the same torque. If you port the heads, you can add another 10-20rwhp. This cam will make the torque peak rise ~1k RPM, but the beauty of a 2400+ converter will make you launch roughly within 500 RPM of that peak. And with any mods, you need to get rid of those 2.59s for a set of 3.07s.
Thanks for all the great info both of you guys! I'm trying to make about 350rwtq, and 270rwhp....Is that feasible with 1k if i do my own labor? Or should i budget a little more? That is minus the TC and Gears
Team Owner
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From: Athens AL
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Hmmm, a stock 89 automatic should put down about 210rwhp/300rwtq or thereabouts. You would need about 50-60 on each side, for $1000 it can be done, but you need to be the one doing the work and you wouldnt be able to buy everything new. You would need a little luck in getting parts cheap.
Buying a SR would likely take all of that budget.
I would definitely buy any camshaft new. A cam like the ZZ9 or Accel 211 would be my first choice. 1.6RR definitely. That would take up at least a third of your budget, likely half.
You would need to look for the runners on ebay, fully porting your own might not get there. Similarly for the base manifold. You may only be able to buy one of the two, so I'd buy the manifold if push comes to shove.
You would then need headers and exhaust, that would likely put you over this budget.
Buying a SR would likely take all of that budget.
I would definitely buy any camshaft new. A cam like the ZZ9 or Accel 211 would be my first choice. 1.6RR definitely. That would take up at least a third of your budget, likely half.
You would need to look for the runners on ebay, fully porting your own might not get there. Similarly for the base manifold. You may only be able to buy one of the two, so I'd buy the manifold if push comes to shove.
You would then need headers and exhaust, that would likely put you over this budget.
Thread Starter
Burning Brakes
Joined: Aug 2007
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From: salinas ca
Hmmm, a stock 89 automatic should put down about 210rwhp/300rwtq or thereabouts. You would need about 50-60 on each side, for $1000 it can be done, but you need to be the one doing the work and you wouldnt be able to buy everything new. You would need a little luck in getting parts cheap.
Buying a SR would likely take all of that budget.
I would definitely buy any camshaft new. A cam like the ZZ9 or Accel 211 would be my first choice. 1.6RR definitely. That would take up at least a third of your budget, likely half.
You would need to look for the runners on ebay, fully porting your own might not get there. Similarly for the base manifold. You may only be able to buy one of the two, so I'd buy the manifold if push comes to shove.
You would then need headers and exhaust, that would likely put you over this budget.
Buying a SR would likely take all of that budget.
I would definitely buy any camshaft new. A cam like the ZZ9 or Accel 211 would be my first choice. 1.6RR definitely. That would take up at least a third of your budget, likely half.
You would need to look for the runners on ebay, fully porting your own might not get there. Similarly for the base manifold. You may only be able to buy one of the two, so I'd buy the manifold if push comes to shove.
You would then need headers and exhaust, that would likely put you over this budget.
......So with LTs and ported runners/base would it be worth it to get a tune? And should i pickup a cam kit that has EVERYTHING? springs/cam/retainers/lockers/rr's?
Team Owner
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From: Athens AL
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Yes, I forgot to budget the tune as well. If you change the cam, this is required. If you dont change cams then dont do this yet.
It would be better to buy new valvetrain parts when doing the cam, yes. Not necessary to buy all in one kit, but do get springs that will work for that cam.
It would be better to buy new valvetrain parts when doing the cam, yes. Not necessary to buy all in one kit, but do get springs that will work for that cam.
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
Thanks for the informative reply again vader, well i already have the exotic muscle LT headers sitting on a shelf waiting to be put on, then i'm going with a hi flow main cat and 2.5" all the way back. I will be doing all the exhaust work myself, as will i be doing everything else too. So i'm just worried about the parts budget, the labor is free ......So with LTs and ported runners/base would it be worth it to get a tune? And should i pickup a cam kit that has EVERYTHING? springs/cam/retainers/lockers/rr's?
......So with LTs and ported runners/base would it be worth it to get a tune? And should i pickup a cam kit that has EVERYTHING? springs/cam/retainers/lockers/rr's?
