L98 to Lt1
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L98 to Lt1
I am about to convert my l98 with lt1 heads and intake. All the required machine work to the heads and intake are supposed to be done. Here is my question. It is a 86 model so will I need a new wiring harness and also what headers to get now that the lt1 heads will be on it? Thanks.
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Well I am buying off ebay. The seller said the intake was drilled for distributor and that the heads were welded. I dont have them yet but I should receive them on Friday. What else should I do while I am in there? I have a 282 duration .480 lift cam with 1.52 roller rockers I want to install. Will I have to get a custom tune?
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Should I just buy a custom "chip" or take it somewhere. I have read there are ways to program and tune with a laptop? After headers go on and a good tune how much hp gain do you think I will get? Thanks so much for this info.
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From: Park City Utah
That is out of the realm of what I have first hand experience. I know that you can buy hardware and software to tune w/a lap top. Rather than regurgitate that which I have read, but don't know first hand, I'll let someone else who does have first hand experience give you the details.
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Melting Slicks
Joined: Jun 2013
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Try Lt1pcmtuning.com for email order tunes. You will data log and send the logs to him and he will send you a tune. You will keep doing this until the tune is good, unlike some other places that give their best guess. As for the power gain, depending on the cam that you're using, if it's equivalent to the LT1 stock cam or superior it should be at least 300 hp at the crank. With the headers I'd say 320. If the cam is superior to the LT1 cam, then obviously you're going to be able to get a little more.
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With all my research everyone says the L98 heads and intake are very limited in what you can do in performance. I would like to see 350hp at the crank but we shall see.
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Well I got my intake all cleaned up and painted. Got the heads having the valves lapped and installed with new springs. Now just hope this combination works. I did have to purchase a new dizzy as the large cap hei will not fit without major machine work to the back of the intake. I am gonna go ahead and install a msd ignition while I am at it. Is the .30 overbore ok on a 86 block? I know they go .30 over on a 383 stroker but mine is not a stroker. I measured the stroke and it is 3.5 inches which I think makes it a standard 350 crank.
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Ok. I hope someone can help me out here again. Like I said above I now have my engine tore down and I have found something that kindof makes me nervous. As per my above post when I got the heads off I measured my bore which was 4.03 which I assumed a .30 bore size. Well today I was cleaning it all up and found P1534 060 stamped on top of the pistons. According to my research these are Enginetech pistons with a .60 overbore. This bothers me as to the engine build previous and having a block bored .60 over. But why does my calipar only measure 4.03? Please Help!
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OK first off it's .060 and .030 but anyway I'd guess you didn't "ZERO" your vernier caliper before you measured. I'm guessing you're using an inexpensive vernier that can be "ZERO'D" at any specific opening. You need to collapse the vernier to 'closed' and then 'ZERO' it. Not knowing exactly what tool you're using it's difficult to relate but that's the only explanation that comes to mind. Look inside of a piston and see what's cast on the inside. Maybe you've got some mis-stamped pistons. Maybe they were stamped .060 intentionally by someone. Stranger things have happened!
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It is one of those caliper tools like from AutoZone. I closed the tool all the way then pressed the zero button. I then slide it open until the flat edges contacted the cylinder walls. It read 4.032. Id this is the case there is no way they got .60 over in that cylinder and still be able to rotate engine, right? Also, if it is .60 over, thats not good either, am I right on this. Thanks.
Melting Slicks
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Hmmm..
interesting.....I was thinking the water jackets would not line up with the LT1 heads with the Gen I block...the LT1 is a reversed cooled system.....learn something new every day I guess...interesting thread....
interesting.....I was thinking the water jackets would not line up with the LT1 heads with the Gen I block...the LT1 is a reversed cooled system.....learn something new every day I guess...interesting thread....
Team Owner
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It is one of those caliper tools like from AutoZone. I closed the tool all the way then pressed the zero button. I then slide it open until the flat edges contacted the cylinder walls. It read 4.032. Id this is the case there is no way they got .60 over in that cylinder and still be able to rotate engine, right? Also, if it is .60 over, thats not good either, am I right on this. Thanks.