better l98 mod: headers vs lt1 converted intake
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From: PA
better l98 mod: headers vs lt1 converted intake
the title of this post pretty much says it all. Currently the only mods I have done to my early model iron head l98 is magnaflow cat-back. Both the lt1 converted intake and headers (hedman elite) seem to run about $400. which would gain more hp??
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From: Phila., PA burbs
I'd say headers which will probably net you about 15 rwhp. I don't think the LT1 intake is going to do much for you by itself. If you were to put a new cam in and some head work the LT1 intake could perform nicely. With no other mods I'd definitly go the header route. 
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LT headers will add power across the power band, while intake mods will cost low end and add high end; this will require manual shifting or reprogramming of the governor.
BTW, you should also to a hi-flow cat or "test pipe" to fully benefit from the exhaust mods.
BTW, you should also to a hi-flow cat or "test pipe" to fully benefit from the exhaust mods.
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with a cam, tuning, and maybe the headwork....the LT1 intake will have more potential
but by itself, it will need at least a custom chip...that will make more power than the headers, alot more but the chip must be done
but by itself, it will need at least a custom chip...that will make more power than the headers, alot more but the chip must be done
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From: PA
tough decision, but you guys have shed some light on things. i forgot the tpi intake is benificial in the low end rpm range. i was concerned about adding headers due to all the heat they put off. won't that compromise the life of some of the electronic components (i.e. starter, distributer...)?? my engine only has 30,000 miles, but i guess a starter here and there isn't too much hassle to replace.
Team Owner
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From: Boston, MA
If you are going to ONLY put headers or an intake on then go with the headers. An LT1 intake is going to require more work to get you anything (ie. camshaft, tune, pushrods, lifters). You'll be mixing a low-mid RPM camshaft with a mid-high RPM intake.
Last edited by scorp508; Feb 5, 2007 at 04:08 PM.
Le Mans Master
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tough decision, but you guys have shed some light on things. i forgot the tpi intake is benificial in the low end rpm range. i was concerned about adding headers due to all the heat they put off. won't that compromise the life of some of the electronic components (i.e. starter, distributer...)?? my engine only has 30,000 miles, but i guess a starter here and there isn't too much hassle to replace.
you need to heat shield the starter.
it can melt your brake booster. should shield that.
need to pull your fuel lines away from the headers as well since they run close by.
I would consider ceramic coated headers or heat wrapping them. heat wrap is suppose to wear headers out in a hurry.
Melting Slicks
Joined: Aug 2003
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From: Lakeville MI
I'm kind of surprised with the responses so far. I vote for the intake.
I would expect a header only L98 to make around 230-240 RWHP.
On the other hand, I would expect an LT1 intake or miniram'd L98 to make 260-270 RWHP, maybe even more with tuning.
Kopbet's 89 comes to mind as a good example of this.
An intake base + large tube runner setup should beat headers as far as HP is concerned, a superram even better, an LT1 intake or MR shouldn't even be close.
Of course, any of these choices will most likely cost much more than $400 when its all said and done.
I would expect a header only L98 to make around 230-240 RWHP.
On the other hand, I would expect an LT1 intake or miniram'd L98 to make 260-270 RWHP, maybe even more with tuning.
Kopbet's 89 comes to mind as a good example of this.
An intake base + large tube runner setup should beat headers as far as HP is concerned, a superram even better, an LT1 intake or MR shouldn't even be close.
Of course, any of these choices will most likely cost much more than $400 when its all said and done.
Last edited by tequilaboy; Feb 5, 2007 at 03:20 PM.
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Racer
Joined: Dec 2005
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From: Chicago IL
The LT1 conversion will gain more horsepower at a higher rpm where the stock TPI intake falls off after ~4200 rpm.
There is no full length header that will fit up to the factory front y-pipe. You will need a replacement front y-pipe as the factory unit has 2 outter layers and from what I understand cant be welded to another piece of pipe. So in addition to the headers you have to get a new front y-pipe to the cat. Double check on that.
You can always get your headers jet hot coated to keep things cool under the hood.
Which one would I do??????
The headers.
There is no full length header that will fit up to the factory front y-pipe. You will need a replacement front y-pipe as the factory unit has 2 outter layers and from what I understand cant be welded to another piece of pipe. So in addition to the headers you have to get a new front y-pipe to the cat. Double check on that.
You can always get your headers jet hot coated to keep things cool under the hood.
Which one would I do??????
The headers.
Drifting
Joined: Oct 2005
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From: bakersfield cali
if you go either way, you are going to have to spend more than 400 bucks. the headers alone with the necessary work to get them welded to your y pipe, good gaskets (not the cheap paper ones that come with the headers), and a good set of Coated headers (don't even think of putting uncoated headers, full lenght headers in c4's are too close to every thing) all this is going to put you well over 400 bucks.
i would go to the lt1 intake with a hydroulic flat tappet grind from comp cams. if you want to go cheaper, you can get a generic cam from summit racing. these are like 80 bucks with lifters. the only way to really feel the difference on the intake is to get a cam that matches the charracteristics of the intake. dont forget to add a fresh set of valve springs to go with the cam another 70.
tough choice. both of these mods are worth it.
i would go to the lt1 intake with a hydroulic flat tappet grind from comp cams. if you want to go cheaper, you can get a generic cam from summit racing. these are like 80 bucks with lifters. the only way to really feel the difference on the intake is to get a cam that matches the charracteristics of the intake. dont forget to add a fresh set of valve springs to go with the cam another 70.
tough choice. both of these mods are worth it.
I don't think you can get Elites for $400 with all you will need they will be over $600. Then y-pipes etc..
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For the 2 or 3 in this thread that mentioned that the headers should be coated, the Elites are coated. I don't believe Hedman offers a Y-pipe but I could be wrong. A good muffler shop could probably fab one up pretty reasonably. Finding and adding an LT1/4 exhaust system would be a nice gain with the headers too. They usually go very cheap. Install some bullet cats off of the headers and have a muffler shop hook it to the LTx catback. Now you're talking some nice gains with just exhaust mods. Pypes sells some very inexpensive stainless bullet cats in 2.5" or 3". Later as funds allow, you could replace the LTx resonator with an X-pipe and pick up even more torque.
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From: Boston, MA
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From: PA
yes the heat will cause issues.
you need to heat shield the starter.
it can melt your brake booster. should shield that.
need to pull your fuel lines away from the headers as well since they run close by.
I would consider ceramic coated headers or heat wrapping them. heat wrap is suppose to wear headers out in a hurry.
you need to heat shield the starter.
it can melt your brake booster. should shield that.
need to pull your fuel lines away from the headers as well since they run close by.
I would consider ceramic coated headers or heat wrapping them. heat wrap is suppose to wear headers out in a hurry.
Racer
Joined: Dec 2005
Posts: 384
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From: Chicago IL
I believe somebody named Kopbet or what did the miniram swap on a stock l98. Plus the tpis insider hints catalog shows the upper rpm gains past 4200rpm on a miniram vs stock tpi.
