ive read and heard of people talking about swaping their TPI for an LT1 intake, but i was curious to know what are the actual benifits of doing this? wouldn't that basicly make your L98 run like an LT1 except the L98 doesnt have the reverse cooling? i'd like to know more about this, so if anyone's got any info about the advantages and disadvantages (if any) with swaping an LT1 intake for your TPI, let me know. thanks guys
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The upside is that the LT1 intake flows much better than the TPI intake.
The downside is that you'll only gain about 500 RPM because the L98 heads don't flow well past 5K RPM.
Now if you were to use the LT1 intake and port or replace the L98 heads, then you would definatly see a gain.
The downside is that you'll only gain about 500 RPM because the L98 heads don't flow well past 5K RPM.
Now if you were to use the LT1 intake and port or replace the L98 heads, then you would definatly see a gain.
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My expereince doing this with a very similar Miniram (almost identical to the LT1 except that it has larger runners) is that you lose quite a fair bit of low end torque but pick up on the top end. I'm talking about adding this intake to an otherwise stock TPI motor.
Net net, it'll get you to the end of the track at about the same ET but a higher MPH.
The downside, from expereince, is that the engine likes to rev up top so much better that you'll probably blow up a high-mileage bottom end pretty quickly having fun with the new-found RPM capability. An engine that has spent it's whole life below 4500 is not gonna like regular blasts to 6000 (which is entirely possibly with just this intake swap). Ask me how I know.
Net net, it'll get you to the end of the track at about the same ET but a higher MPH.
The downside, from expereince, is that the engine likes to rev up top so much better that you'll probably blow up a high-mileage bottom end pretty quickly having fun with the new-found RPM capability. An engine that has spent it's whole life below 4500 is not gonna like regular blasts to 6000 (which is entirely possibly with just this intake swap). Ask me how I know.
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Well its not a bad mod to do....but to take advantage of it you would need to do a cam swap and heads if funds allow.
when i bore/stroke out my 350 to something bigger near the 400's ci range, im going to rebuild the engine and put a big nasty cam with some afr's... when i do that i might as well either stick with TPI or put another intake.... thats why i was thinking about the LT1 intake. i plan on putting a supercharger on the engine when im done rebuilding it (forged everything and blower pistons on either a 383, 396, or something in the 400's)... should i just leave it TPI or should i go with something else (like the LT1 intake, miniram, HSR, or other)? only reason i even thought about the LT1 intake was because its cheap, and it'll give me more hp (and a little bit less torque) that the stock tpi can't produce
The stock TPI is not worth much. If you are going to mod an engine, I would first concentrate on the intakes. It is mandatory to get the air in and out. Headers and Intakes first. If you go with non NA engines, I would go with the Miniram as you don't need the low down torque as much.
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I just put a HSR on my comp cams, AFR big tube TPI motor. Holy Sh**! What a difference. With a little 210/220 .513 lift roller cam, the thing will pull HARD over 6000 rpm up to the rev. limiter.
Don't try it with a stock chip. I was a little dissapointing at first, but i'm lucky i have a chip guy who did a lot of programming work for me. What a difference though! The TPI manifold is a peice of sh**, even with aftermarket base/runners etc.... THe car feels just plain FAST now.
Don't try it with a stock chip. I was a little dissapointing at first, but i'm lucky i have a chip guy who did a lot of programming work for me. What a difference though! The TPI manifold is a peice of sh**, even with aftermarket base/runners etc.... THe car feels just plain FAST now.
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Damnit I posted a whole post and it didn't take it....anyway...
I said that you can't make an L98 an LT1 w/ just changing the intake. The heads are different, cam is different, Lt1 has reverse cooling, ignition system is different, etc etc.
Here is a cool link about switching from a Super Ram intake to an LT1 intake on a modified car:
http://www.popularhotrodding.com/tech/0803phr_beast/
They gained some top end power at the expense of a LOT of low end. Port velocity was sacrificed for better top end flow. Again, that's a heavily modified L98 (As you see it put down 335 rwhp). There is a dyno graph and numbers about 1/3 of the way down the article.
I said that you can't make an L98 an LT1 w/ just changing the intake. The heads are different, cam is different, Lt1 has reverse cooling, ignition system is different, etc etc.
Here is a cool link about switching from a Super Ram intake to an LT1 intake on a modified car:
http://www.popularhotrodding.com/tech/0803phr_beast/
They gained some top end power at the expense of a LOT of low end. Port velocity was sacrificed for better top end flow. Again, that's a heavily modified L98 (As you see it put down 335 rwhp). There is a dyno graph and numbers about 1/3 of the way down the article.
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They may have lost some low rpm torque, but the car ran identical times. The engine they swapped the short-runner intake onto was more suited to the SuperRam, Id say the LT1 intake did pretty good and would do much better if the engine had a cam and compression to suit the high rpm torque the intake can support.
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Yeah, I'm sure if you put a different cam in and so forth it would do better. But taking a stock L98 and putting an LT1 intake on it will still make it lose low end torque and gain a little top end power.