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Discussion Starter #1
Ive seen a lot of post about the TBI cam upgrade but none explaining what to do, what its dose to add power and a install procedure, with how to time it and what to time it at. :shrug: So any pictures and how too would be much helpful. Im not new to turbo dodges just never done this before. Thanks for all the help!
 

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i have a tbi cam in my 85 shelby with t2 upgrades and a ported head, now it will pull to 7500 it doesnt lay over or fall on its face like the turbo cam does at those rpm's i have to say i like the cam becuse it doesnt really effect the way it runs down low drives normal!

and if you have a tbi cam that you have the followers for just remove your cam and followers and put the tbi cam in its place,
 

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Discussion Starter #5
Im actually gona run the TBI bottom end well my T1 bottom end gets built. Im gona run it on regular gas so it stays at 7psi, so i get the most life i can out of it well still bossting a little :p
 

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The TBI cam is closest to the slider turbo cam in duration, the TBI is 236/232 and .430 lift.
The 89 and up turbo roller cam is 228/228 with .430 lift.
The TBI cam is also 4 degrees retarded from the 89 up turbo cam which will decrease low end torque and increase high rpm HP.
You can accomplish the same thing with an adjustable cam sprocket.
You probably will not notice any difference from the slightly higher duration.

 

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It may be, I would have to reference DDG to be sure but that is only one year since 87/back were slider cams.
 

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Isn't the duration of the 88 turbo roller the same as the TBI cam? I know it's more than the 89 turbo roller for sure.
the 88 turbo cam is barely different than the TBI. But when you buy new cams or regrinds you end up with 1 turbo roller and 1 TBI. So it is hard to tell them to look for a 88 turbo cam because it is like finding a unicorn lol.

The 85 slider was said to be the best HP making factory turbo cam (Dave Z claim BTW), the TBI is basically the same cam minus 2 degrees of duration.

In NA cars retarding the cam makes more power, with most TDs with a stock flowing 8v advancing the cam makes more top end not less. That is why the 88 TBI is popular, it adds a little advance being run in a round tooth pulley turbo engine.

Gets confusing pretty fast though lol
 

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Ok, I'll pitch a penny in the confusion bucket. What if you didn't advance the tbi cam in a turbo motor, leaving it 4 degrees retarded? Compared to advancing it? What would the result be?
 

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Ok, I'll pitch a penny in the confusion bucket. What if you didn't advance the tbi cam in a turbo motor, leaving it 4 degrees retarded? Compared to advancing it? What would the result be?
less spool up and about the same power as before. Advancement is more important than you'd think on most TDs. The first roller I added was an 89 Turbo cam after the 314 slider ate a lobe. The ate lobe slider made a considerable difference in power and spool up even screwed up over the roller. But this was a late cam in an early engine. If you have a late engine it doesn't matter. A square tooth pulley 2.2 owner needs to get a 88 TBI or an adjustible cam gear or key. Even still, all that a side when I first started pushing the TBI it was dyno tested by a lot of different people and they all got a little gain from advancing it a little farther.

Boostgeek and Shadow most likely would lose power from advancing, because of the mods. A log engine or an engine with a 1 piece is a different matter (yes I know both of these guys run a 1 piece but there heavily cut on lol).
 

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Discussion Starter #15
Ok so if im running a 1 piece witch i am, all the rest is stock i should leave the turbo cam in it then and wait for more mods to run a tbi? Im so confused lol
 

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I have always read that the camshaft was the last thing to change in a turbo car in order to get more power ...
 

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Even still, all that a side when I first started pushing the TBI it was dyno tested by a lot of different people and they all got a little gain from advancing it a little farther..
By a little farther, do you mean a little more than 4 deg advanced?
Or stop at 4 degrees advanced for the stock motor?
 

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Ok so if im running a 1 piece witch i am, all the rest is stock i should leave the turbo cam in it then and wait for more mods to run a tbi? Im so confused lol
no you can run it right now, just advance it so it works better if your running an old square tooth pulley engine. The TBI helps people that have low flow. The best cam choice for low flow, a stock 1 piece, stock 2 piece, etc with an intercooler. Log engines are a bit different and they like more cam, like the 314 and 767 sliders. So even the F2 would help. But the log engines come with a bigger turbo than most later T1 cars and they don't have any plenum so you aim for power with low boost. A car with a mitsu and a 1 piece intake can't use a bigger cam, way too much back pressure. TBI is at this point the farthest you want to go
 

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Discussion Starter #20
Ok my car is an 87 T1 lebaron square tooth, which originally had a log intake manifold on it. im switching to a 1 piece Late T1/T2 setup. Im also gona be running an 91 TBI bottom end just tell my turbo bottom end gets rebuilt later this year. Im only planing on running 7psi max on it. so with that being said, and from what you guys have said, im thinking i should wait to run the TBI cam. So i must have the large turbo then right?
 
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