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Discussion Starter #1
Hey everybody, I was wondering if you could put a 2.5 t1 block in place of a 2.2 with a log intake bump up the timing and run it for the street ?
 

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I have heard of many people running 2.5 engines on 2.2 electronics. Most however are with blow through top ends and not log draw through top ends. You will need to run a bigger injector for sure. I broke in a 2.5 engine with +20 injectors at full or near full base fuel pressure, and it ran near perfect. This was on a LM car (87 SL). Did this only until a custom tune could be procured.
I think most people would just upgrade the top end considering you are already changing out the entire engine anyway. The intake log manifold is terrible flow wise. With that said I do have a pretty stout log manifold GLHT that has ran 111 MPH traps, so It's not like I dislike them or anything. They are just pitiful from a flow and design standpoint vs the 1 & 2 piece intakes and of course the much larger throttle bodies.
On the plus side for pull through turbos, there is no need to run a BOV, so thrust bearing of turbo will be happier than with blow through turbos.
 

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Discussion Starter #3
Thanks for the quick response !! I had an idea on increasing the overall diameter of the log intake to a 3" aluminum tube and a TBI header. I really did not want to modify the harness.. BTW the car is an 87 lancer with the FWD performance 12 psi lm
 

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Thanks for the quick response !! I had an idea on increasing the overall diameter of the log intake to a 3" aluminum tube and a TBI header. I really did not want to modify the harness.. BTW the car is an 87 lancer with the FWD performance 12 psi lm
IMO, the biggest issue in the log manifold is not the lack of size of plenum, but where the boss for the injector rides in the port. The boss basically is sitting right in the middle of the port. It reduces the size of the port by about a third! Some careful porting can make it less restrictive, but it will always be far worse than a later style intake manifold.
If I were you, I would never bother with larger plenum and TBI header if using a poor flowing intake manifold like the log is. I would rather concentrate on making the log intake the best it can be through porting, welding, etc, to reduce the restriction of that intake. Then, if you get the log manifold flowing better, then the very small throttle body can become a restriction. Biggest bang for the buck is to intercool it. Back 30 years ago, my GLHT went from running 14.90's, to 13.90's just with intercooler addition. That is without changing boost level! That was a huge gain. That allowed me to then increase boost from 12 PSI to 17-18 PSI. After adding more fuel, car then ran in low 13's in street trim (DOT tires) at 106 MPH. Another huge increase.
 

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Discussion Starter #5
I have a stocker IC from a t2 car, although Ill bet a rolling rock that I'd be better off with a large fmic ( please correct me if I'm wrong on this) As for the TBI header I wanted to move "some" of that heat away from the intake manifold. I read somewhere that it can boil the fuel in the rail on a hot start. Had a big valve ported head 287 somewhere but.. Id like to save that for something else.
 

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The stock TII intercooler is okay until you get into close to doubling the stock HP. If your curious, you can do some digging on the two forums, you might find some airflow, pressure drop, and efficiency ratings of various factory Chrysler intercoolers. I do remember the VNT intercooler being the worst of the factory coolers. Lots of low quality FMIC out there, do your homework when looking for one. Yes you might gain some pressure drop efficiency at high boost levels going with a large quality FMIC, but you also increase the chances of blocking off airflow to radiator. You wouldn't be the first person to have their car run warmer than desired after installing a FMIC.
I ran a TBI header on one of my GLHT's. First you have to make sure someone that knows what they're doing welds it. The one shown below was flame spray welded. Lots of stories about failed (cracked) TBI headers. Then there is plenty of porting to do at the turbo flange and ports. The TBI header also requires mods to the swingvalve unless you're planning on running a V-band swingvalve of some sort. Of course, oil & coolant lines, exhaust downpipe mods, and relocating turbo inlet/outlet plumbing are also required. In your case running a draw through turbo, the TB will need to be relocated too due the turbo moving a bunch. Your correct, the TBI header will help keep some heat off of the intake, but your rack and pinion steering will be terribly close to the downpipe. Some sort of heat shield for the rack will need to be fabricated. Been down that road before. Lots of fabrication making a TBI header work.
The factory log cars came with a heat shield. The later TI and TII cars did not, so there is that. Make sure your factory heat shield is in place and is in good shape. Lots of people do various mods to keep heat away from intake on the later applications. Coatings, heat shields, downpipe and exhaust scroll wraps, phenolic spacers between the upper and lower halves have all been used with success.
Good luck!


IMG_6109a.jpg IMG_6110a.jpg IMG_6114.JPG IMG_6116.JPG
 

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I have a stocker IC from a t2 car, although Ill bet a rolling rock that I'd be better off with a large fmic ( please correct me if I'm wrong on this) As for the TBI header I wanted to move "some" of that heat away from the intake manifold. I read somewhere that it can boil the fuel in the rail on a hot start. Had a big valve ported head 287 somewhere but.. Id like to save that for something else.
One of the members here runs 10.0 at 145 with a ported factory manifold and a small valve head. The power is in the intakes. Instead of trying to make every drop of poor drive pressure work with a TBI. You create more drive pressure maintaining boost at the intake valve. True the plenum will help greatly, but your computer starves 2 cylinders for fuel to deal with flow and the TB is only 42mm. So with the log engine it is kind of like going to a 426 Hemi but restricted to running only a 2 barrel. Better to build something right the first time or be happy running something more mild.
 

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Discussion Starter #8
I agree with do it right the first time. I am currently building a 93 CB with a 2.5 crank srt4 OEM rods. ARP bolts flat top pistons, ported 655, solid lifters, roller camshaft specs are 240/248°, 24° overlap 110° centerline .528 lift. The turbo is a hx30 but to make sure I have firewall clearance I am using my h1c as a mock up. TBI header to keep that turbo responsive. Being a draw thru setup, had planned on using e85 for street and water meth injection for added insurance. BUT I ran into an issue with the electronics, I cannot run the higher compression 9:5.1 to 10:5.1 I had initially intended to without going to a standalone setup. I can get it down to 9 with a thicker hg and some more chamber work. As for the intake I had worked out that 2 3/4 was the max I could get to without the TB being a major restriction. This was/ is my mild build for this car... Nuts would be a 2.0 dohc long rod 2-71 build....
 

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Discussion Starter #9
I agree with do it right the first time. I am currently building a 93 CB with a 2.5 crank srt4 OEM rods. ARP bolts flat top pistons, ported 655, solid lifters, roller camshaft specs are 240/248°, 24° overlap 110° centerline .528 lift. The turbo is a hx30 but to make sure I have firewall clearance I am using my h1c as a mock up. TBI header to keep that turbo responsive. Being a draw thru setup, had planned on using e85 for street and water meth injection for added insurance. BUT I ran into an issue with the electronics, I cannot run the higher compression 9:5.1 to 10:5.1 I had initially intended to without going to a standalone setup. I can get it down to 9 with a thicker hg and some more chamber work. As for the intake I had worked out that 2 3/4 was the max I could get to without the TB being a major restriction. This was/ is my mild build for this car... Nuts would be a 2.0 dohc long rod 2-71 build....
I should add that the car as the 12psi FWD performance LM in it ( came that way when I bought the car) from reading the site that's for the t2 cars. Tomorrow when I get out of work I'll take some pics vids of the car no better way that to see/ hear what I'm working on..
 

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if you live in a place with large hills...

the SINGLE BEST MOD FOR THE LOG MOTOR
is..
the MP 314 cam and the MP LM ..

first the MP lm gets an L body to the top of the grade shown below at 50 mph

the corner at the bottom of the last pic is a 25 mph corner
-second corner on hill

the 314 cam gets it to the top of that grade at 75
- more if I didn't have to hold it back going over the top to stay outta the ditch

no intercooler on earth is gonna do that
sorry I don't have a pic of the top section and "level" is slightly above the top of the dead tree,center of the last pic.. it's really that steep

20mph and the potential to prove even more
- that's results a trip to the dyno won't give ya either
"what does it really do??"

not shown is the hill on the opposite side of the valley
it is from the same height but much straighter soooo.. there might have been somebody... going 140 way way long ago...

and , I've done that crooked little steel deck bridge at 115mph
there's a huge dip after and NO BRAKING until you reach the shadow line halfway up in the first pic..

nurburgring.. eat your heart out I have something better (had)
I'm older and more "responsible" now so sorry no videos will be forthcoming...
download (2).jpg
twyn_riversdr1jpg.jpeg
Rouge.2.jpeg
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twyn-rivers-down-39871.jpg
 

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log motor... no intercooler
305 fd carb trans (proven unbreakable)
MP LM
314 cam
accel air filter
stock shelby charger running gear in turismo..

also never beaten by ANY five liter mustang in the day..

avatar is the view from my driveway of 47 years looking at the view of the valley and the cliff in the pics

...where after one of those pulls up the hill my turbine housing would still be glowing cherry hot.. so it was probably see through topping the crest of the hill 30-45 seconds before
 

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Discussion Starter #12
First that would be one hell of a fun road to run, I am officially jealous. Reminds me of that show BMI (best motoring international) Touge. I have the 87 MP logic module just not the cam. Sounds like it already has a roller cam in it though I'll get the numbers off that LM today gotta check on the van before 5pm..
 

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Discussion Starter #13
It says 1piece, r5227241 logic module. Still new in a box it has a black port with as pin count of 25 and a clear/ white port with 25 pins as well as a plug for what I assume is the map sensor.
 
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