4bangerjp.com
General Forums => The Mess Hall => Topic started by: bigal389 on October 22, 2013, 08:31:12 PM
-
Ok here goes. I'm planning to build the engine in my 87 Yj over the winter and have a few questions. I tried searching and found nothing solid for an answer. So here go the details, port and polish the head, deck the block to be sure it's flat, new pistons 10:1 hopefully if I can find any, gasket the intake and exhaust and a Clifford cam. Now for the questions, has anyone ran a Clifford cam with tbi and if so how did it do? What was done to add fuel? I contacted Clifford and they told me their cam didn't do well with fuel injection and that I should run a carb. I have no problem with this but I would like to know how it performs with tbi before I sink a bunch of $ to loose my tbi. Has anyone upgraded the tbi in any way? I'm sure I'll have more ? As the build gets closer.
Thanks, Al
-
you'll need a 91+ head and pistons, i think the block is the same.I'd also look into getting MPFI installed instead of TBI
-
Just curious, why 91 and up head and pistons?
Thanks, Al
-
Just curious, why 91 and up head and pistons?
Thanks, Al
+ intake also. The TBI is probably pushed to the max with the 117HP output, the MPFI Wrangler is actually tuned down (same engine in XJ has more power).
head has better flow, the pre 91 pistons are flat head (if I'm not mistaking) and better efficiency overall, the a/m cam would work better with the newer head and pistons. If you go 10:1 you'll probably need to up the octane, so something to consider as in cost in the long run (might be a wash since would probably be using less gas but that's TBD).
-
Just curious, why 91 and up head and pistons?
Thanks, Al
91 is when they switched to the HO 4.0L
-
thanks to sharp i had a bored out TB on my 1990 tbi before i sold it. it livened up the engine nicely especially at higher rpms. The fuel regulator is very similar to those on chevy tbi s and if your adventurous enough i think you can adjust it. you have to drill out a metal plug in the bottom of the regulator bowl to access the adjusting screw if i remember correctly. I didn't do any cams or headers so i cant speak for tbis response to bigger upgrades. you can also use larger injectors from chevy tbi engines. I have a thread on here somewhere comparing flow rates. i think the chevy 5.0l injectors are slightly bigger than stock 2.5l...
-
Ok so I need a 91 or newer head and pistons to get the cam to work well. I had thought about doing the mpfi swap but there aren't many jeeps around here to salvage the parts from. Are there any throttle bodies that will work with the jeep intake or am I just waisting time trying to make tbi that's on it better?
Thanks, Al
-
There are no other throttle bodies that will fit on the TBI intake that are bigger than the stock one. I wouldn't be so down on the TBI. The number of TBI 2.5s on this forum is very low so not a lot is known about their ability to adjust for cams and what not. If i still had my jeep I would have been doing a simular build with stock heads but I bought a rubi instead because of frame root. No garenties though.
-
I do have a spare tbi intake I may do some experimenting and set what I can come up with.
-
actually i was wrong, 87 has the same piston, so scratch what i said (i looked up the part numbers and they're the same).
-
Ok thanks, I'm going to research a bit and see what I can find out on the tbi to mpfi. If I remember correct some Dakotas had our 2.5 in so I may be able to get the parts needed there. I'm still going to play with the tbi some aas well in the mean time to see if I can do any mods to help it any.
Thanks, Al
-
Sharp, can you give me some info on the bored out throttle body? This is something that I want to try along with some other mods.
Thanks, Al
-
Sharp, can you give me some info on the bored out throttle body? This is something that I want to try along with some other mods.
Thanks, Al
i took the t/b apart and bored out to whatever the max diameter i could get out of it, there's some pics in the garage sale
nothing special really
-
i still have the tb spacer on my desk if you want it (or if sharp wants it back). does me no good without a tbi jeep to put it on....
http://4bangerjp.com/forums/index.php/topic,8142.0.html
http://4bangerjp.com/forums/index.php/topic,10049.0.html
-
I am defiantly interested in the spacer, I plan to bore the throttle body as so I can find a spare.
-
I Still have my stock throttle body (just the lower part with the throttle plate. Send me a PM and we can figure out shipping and cost.
-
http://4bangerjp.com/forums/index.php/topic,4044.0.html
-
http://4bangerjp.com/forums/index.php/topic,4044.0.html
They're talking about the TBI engines.
-
Pm sent.
-
I have a few questions on cams! The cam profile that was recommended By Geoege at Clay Smith Cams is as follows:
Advertised Duration :264
•Duration at .050" : 214
•Lobe Separation : 110
•Valve Lift based on Rocker Ratio
•1.5 .450
•1.6 .480
•1.75 .525
My question is: Will this be too much lift with 1.6 ratio for the stock springs, will I have coil bind at .480 lift? Geoerge said he didn't think I would need to upgrade the valve train unless I planned on running at high rpms which I don't. Hopefully with this cam, a bump in compression, porting and a bore throttle body and spacer my little 4 banger will really wake up!
Thanks, Al
-
Ok I got the throttle body and spacer from Chardrc, I am planning on getting it bored as soon as I can. Also i plan on using the butterfly from a 1987 4.0 low output which has a 52 mm throttle body, this will be easier to cut down than a larger butterfly. After thinking about it for a few days I will keep the compression below 10:1, I am just going to clean up the mating surfaces on the head and block, I figure the final cr will end up between 9:5 and 9:8 depending on how much I have to bore the block. i will install the cam from Clay Smith Cams, port match, port and polish and add a cai and exhaust. I figure with all of this it should give it a nice little kick in the pants. I won't be able to get started until after the first of Nov. but I will keep you all posted once the work begins.
Al
-
Can't wait to read about the results. Do not forget to take pictures. :popcorn:
-
remember you'll have to pay more for gas with that CR
-
Yeah I know but keeping it below 10:1 should help with the octane that it needs. When you bore the throttle body was enough material left to take it to 52 mm or was 50 the max? I ask because I haven't had a chance to measure yet and if I can take it to 52 it will save a little work on the butterfly.
Thanks, Al
-
Yeah I know but keeping it below 10:1 should help with the octane that it needs. When you bore the throttle body was enough material left to take it to 52 mm or was 50 the max? I ask because I haven't had a chance to measure yet and if I can take it to 52 it will save a little work on the butterfly.
Thanks, Al
honestly i think i bored as much as i could safely do it, you can probably sqeeze another mm in there but keep in mind that is cast so it is not perfectly concentric with the outside diameter to begin with so you will end up with some areas that are thinner (which would be your limit). You'll have to make a jig for the butterfly, it has to be machined round with the butterfly at an angle, otherwise you risk of having too much air bleeding around it.
-
Thanks I was kinda stumped on the butterfly part but now I see exactly what to do. I'll let you know how it turns out.
Al
-
I have the Hesco RVOB cam for the 4cyl, its a Clay Smith when it arrives... :)
http://www.hesco.us/products/7735/cylinder-heads/167924/rvob4-25l-camshaft Note the warnings on the page....
My builder machined the spring pockets on the head to keep the springs from binding, If I recall it needed about .050.
I did new springs. stock rocker arms. 4.0 adjustable timing set. (Gets rid of tensioner)
There actually are several different pistons used in the 2.5 when my builder got to looking into it if I recall the post 95 pistons were similar to a hyperutectic and came coated.. This was to prevent the piston slap the jeeps had issues with from the factory.. I've got 85K on mine and good so far.
Cheers
Dave
-
how does the non-tensioner timing chain adjust? (i replaced mine including the tensioner and that piece of plastic is prone to fail so i'm interested in this one for future reference).
-
How does it perform with the RVOB cam? The cam I'm looking at is similar to it. I'm also interested in the adjustable timing set, got any info on it?
Al
-
how does the non-tensioner timing chain adjust? (i replaced mine including the tensioner and that piece of plastic is prone to fail so i'm interested in this one for future reference).
nevermind, it adjusts the timing offset not the chain. in the end I don't know what's worse, using the plastic tensioner or having one without it like the 6 cylinder, I wish someone would have come up with a better design for the tensioner itself.
-
nevermind, it adjusts the timing offset not the chain. in the end I don't know what's worse, using the plastic tensioner or having one without it like the 6 cylinder, I wish someone would have come up with a better design for the tensioner itself.
There used to be a gear set by Mopar Performance as well.
-
i could hear the chain vibrating at high rpm, the chain was actually good and the sprockets looked in good shape also, the problem was with the tensioner as the little plastic teeth got worn out and would move up/down - the bracket was polished under the little leg which tells me that was vibrating there like crazy. on the other hand with the no tensioner design is even worse once the chain or sprockets wear out. I've seen other cars that have an oil pressure fed tensioner which i think it's way better (it is also oiling the chain thru a tiny hole in there)
-
Harley up till 2007 had a spring tension Tensioner. The spring was a monster spring and it ate the shoes right up only got about 30,000 miles out of it. So last year I changed mine over to what the 2007 has which is tension by oil pressure. But I also had to change out the oil pump cause mine was too low of pressure.
-
How does it perform with the RVOB cam? The cam I'm looking at is similar to it. I'm also interested in the adjustable timing set, got any info on it?
Al
It gives you back a gear.. IN my case anyway. I have a long long steep hill that before the rebuild I could never pull in 5th, and barely in 4th..
It now pulls easily in 4th and as long as I hit the hill at 50 will pull it 55+ over the top in 5th.
Oh and I forgot the 4.0 throttle body with spacer in the list.. :) The IDLE of the RVOB is nice, you can tell its not the stock cam but only if you are used to the sound of the 2.5, I also have a 2.5inch exhaust, Clifford Tri-Y Header, and a Spintech muffler.. Above 3000 there is NO doubt something is different. It snarls.
With my rebuild I can pull 6000 rpm with no issues.. But my fuel curve has never been "right" the stock ECU does not handle the increased air flow and tends to run rich in the mid range and lean out up on top.
I finally acquired a wide-band and a data logger so hopefully this spring I'll finally figure out if its just the ECU or some sender tweaking things..
Cant remember the exact degrees my engine builder dialed the cam in at , but we didn't use the most aggressive setting as I have to pass emissions and we were afraid full timing would have prevented that. That's another thing the wide band will help with.
Dave
-
FYI I have over 70K on my rebuild and the 4.0 chainset is still nice and tight without a tensioner..
Dave
-
FYI I have over 70K on my rebuild and the 4.0 chainset is still nice and tight without a tensioner..
Dave
i might bite the bullet and get one when i rebuild mine, seeme a lot better setup than the plastic pieces with the other one (which by the time you actually need it is worn out anyway).
-
Ok here's a quick update: I pulled the head off my 2.5 last night after doing a compression check which failed miserably, I really don't see how it was even running, the cylinder with the highest comp. only had 87 psi. Any yes I thought my gauge was off so I borrowed another one, they were within 2 psi. This was done with the throttle open wet and dry. Wet gained 5 psi.
After pulling the head it was obvious why there was ok compression. It was already .060 over and had a .020 wear ring around tops or the cylinders. So I found a 2000 model engine with a fresh rebuild, wiring harness, all sensors, acc. and ecu for a very good price. How difficult will it be to do this mpfi with obd2 into an 87?
Thanks Al
-
hmm, i've heard of tbi models converted to 91-95 (basically the entire engine and cab harness replaced along with the speedo/tach and gauge clusters. It can be done but you will need to solve your instruments/dash lights as well. On top of that you would also need the fuel pump assembly installed in your tank, on TJs is a returnless system running at 49psi, yours is something like 20psi (i can't remember exactly but it's low even compared to YJ).
the other option you have is to just replace the engine and keep your existing fuel injection, senders, distributor, intake/exhaust and accessories (alternator, power/steering, etc) which i think would be a lot easier and with less headaches.
-
Yeah I was thinking the same thing it would be a lot less trouble to swap the tbi stuff over to the new engine and just add the cam and roller rockers for now.
Al
-
only thing i'd worry about with your tbi is the size of the t/b. Other thing that i'd research is if you can delete the EGR (with a block off plate).
One thing to mention is for the TJ motor you'll have to drill a hole in the head for the temp sender for the water temp gauge or drill one in the thermostat housing and extend the wire, TJ only has one temp sender for the PCM in the thermostat housing and the gauge is driven by the PCM and not measuring directly from the sender as with the YJ.
-
I think I'll need to swap the intake to the tbi intake. Will doing an egr delete hurt anything on the tbi engine? What size hole do I need to drill and tap for the temp sender?
Thanks, Al
-
I think I'll need to swap the intake to the tbi intake. Will doing an egr delete hurt anything on the tbi engine? What size hole do I need to drill and tap for the temp sender?
Thanks, Al
thread is 1/8'' NPT for the temp sender (standard size for these)
I don't know about the EGR, i've seen it on other cars but don't recall hearing or reading about it for the YJ TBI (91+ does not have egr including TJs).
-
I thought i had heard of someone having had done an egr delete on a tbi yj on here but never went into details. it would be simple to just make a plate to bock the port on the intake manifold and another to plug the exhaust manifold port (or use the TJ exhaust manifold). the question would be if the ecm would figure out that the egr isn't working or if it would end up leaning out the mixture when it thinks exhaust gas is being added.
found the thread: http://4bangerjp.com/forums/index.php/topic,9553.msg81610.html#msg81610
the user didn't go into much detail and did a pretty extensive change of retrofitting the tbi system to a mpfi manifold. haven't heard anything from the user in years so don't have a good feel on the longevity....
-
mixture would be based on O2 closed loop, in open loop EGR should be off anyway (even until it warms up).
-
mixture would be based on O2 closed loop, in open loop EGR should be off anyway (even until it warms up).
your right, forgot that egr is only used in closed loop. :brick:
-
That's good info to have! I may try the egr delete. I'm also working on getting the throttle body bored to match the spacer that I got from Chardrc.
Al
-
I would definitely get the manifold bored to match the larger tb especially since you will have the manifold off the jeep anyways so you can make sure no chips get into the engine.
-
Just finished gasket matching the intake and exhaust manifold and believe it or not the head had already been done. I got the intake bored to match the spacer also. While I was at it I tapered the sharp edges toward the runners on the intake. The engine had a couple thousand miles on since it was rebuilt but since the head was already ported I'm unsure what else was done. The guy I bought it from had paperwork with the mileage shows the engine was bored, rebuilt and a performance cam was installed but that's really all it says. I plan on degrading the cam to try to figure out what it is.
Al
-
That should have been degreeing the cam.
Al
-
I haven't had a chance to work on the engine any this week, I have been working a lot this week with the cold. Lots of power outages and when your a power lineman that comes first. I did find that both the manifold air temp. And the manifold coolant sensor are both bad. The coolant sensor has a broken wire at the sensor itself and the air sensor was completely non functional. The problem is I can't find replacements any where. Does anyone have any suggestions for a replacement or an upgrade for these sensors.
Thanks, Al
-
i have no idea what works on the TBI, likely that the IAT is the same as the newer models and possibly so is the coolant sensor but you'll have to doublecheck that to make sure.
-
I picked both sensors today for a 98 4.0, the only ones that I could find. From what I've read when the sensors are warm they should read 1k ohms for both the air and coolant temp sensors on the tbi. I have not found the specs for the mpi sensors but after heating the mpi air sensor with a hair dryer it reads 1.2k so I should be able to wire a 200 ohm resistor in line to bring it within spec. Heating the coolant sensor in water to 200* it read .950k ohms so it should work, I don't think 50 ohms will be enough to make a real difference. Correct me if I'm wrong here but I believe this should work.
Al
-
i wouldn't add the 200 ohm resistor for 2 reasons: 1. i think the thermistor values were unchanged since forever on those, 2. adding 200ohm in series to 1.2kohm would result in 1.4kohm, in parallel would be a little under 200 ohm. Thing is that with thermistors you can't correct the curve since they are not linear so even if you make it a value identical to the specs at a certain temp they would be out of spec at a diffenrent value (and possibly by a lot and make it worse).
just run them like they are and see how it goes, you'll be able to tell shortly after warmup by the way it runs.
-
Thermistors also wont read correctly on a standard Ohm meter. I used to work at a place where we tuned thermistors by trimming the resistor media with a laser. The ohm meter was a very special voltage modulated signal and was a 4 probe unit that could cancel out the lead resistance and contact resistance to the part. If you run power through a thermistor very long it changes value, not always predictably.. If you use a normal digital VM you need to take short measurements several seconds apart and dont keep contact longer than it takes the meter to get a immediate reading.
Dave
-
Oh ok. I'll just give it a try with just the sensor then. I will post more info when I get farther along.
Thanks, Al
-
Here are the TBI coolant and air temperature sensor curves from the FSM.
(http://i164.photobucket.com/albums/u25/chardrc/TBisensors.png) (http://s164.photobucket.com/user/chardrc/media/TBisensors.png.html)
Oreilly had the coolant temperature sensor in stock at the store 2 years ago.
coolant sensor (used by ECU)
MaterPro Part # 2-9384
Murray Part # 36400
BWD Part # WT5011
These only cross reference to Renix fuel injected engines (AMC 2.5l with TBI or 4.0l with Renix MPFI (pre 91). Could just be a different thread to go into the manifold rather than the thermostat housing but I don't know for sure.
Coolant temp sensor for the gauge is BWD Part # WT412 and is the same for all jeeps with the 2.5l before 97
I couldn't find the air temperature sensor on the Oreilly or auto-zone website. The jeep part number is "3300 2382"....
-
Has anybody tried going to a aftermarket GM/TBI controller rather than wrastle the Jeep version?
Youd think something would be out there for the iron duke that would run a jeep.
-
Has anybody tried going to a aftermarket GM/TBI controller rather than wrastle the Jeep version?
Youd think something would be out there for the iron duke that would run a jeep.
Not that I have heard of. Would be interesting since the TB components are so similar. would have to do some work on the distributor as the GM TBI systems use a Cam sensor which the TBI 2.5l jeep engine does not. But between gm parts and the mpfi 2.5l distributor (which has a cam sensor) someone could figure something out.
-
i can't see why you'd spend the time on a TBI migration/swap that is not plug and play and not go with an MPFI to be honest. I can't think of any benefits to make you stay with TBI.
-
Well,, I was just thinking keep it near to the same as possible so the smag nazis around my home base couldn't tell.
Plus the TBI doesn't have the flywheel sensor as I recall? Doesnt it use the dual sensor distributor? Or is that he GM verson?
-
dunno about that, they should be happy with a more efficient fuel system but that's not always the way things work
-
Yea, very little logic when it comes to emissions testing.
-
tbi AMC 2.5l uses a flywheel sensor. no sensors in the distributor at all. just the rotor spinning away in there.
-
tbi AMC 2.5l uses a flywheel sensor. no sensors in the distributor at all. just the rotor spinning away in there.
that makes sense as it doesn't need to know which cyl has the intake valve open (as compared to MPFI where the injector opening is timed with the intake valve).
-
Ah Musta been some other unit I saw with the dual sensor.. Nissan? who knows .. THats what I get for getting old and working on other peoples cars..
Might be cool to put a clifford 2 barrel manifold on and use the double barrel TBI ?? COurse its still a grand to do..
-
well the Chevy tbi distributor has a sensor in it so your not totally crazy (don't know if it is a dual sensor or not). Chevy tbi has no crank sensors so they must be using it for both although as sharp said the tbi doesn't realy need to know which intake valve is open...
-
4 lobes on the dist shaft (like it used to be with the points) would be the same as the 2 groups of 4 notches on the flywheel so really it doesn't matter if its in the distributor, on the cam or on the crank as long as it knows TDC for each 1/2 rotation of the crank will fire a spark and send it to the respective plug via the rotor in the distributor.
-
I'd like to see someone do something with a Holley Dominator EFI. It's a computer that can control just about everything you would want or need. It's not cheap but it does a hell of a lot in a nice package. It will learn which is really nice so you're not SOL when you start it up for the first time.
For emission testing, they really wish they would just check for tail pipe emissions. As long as your not leaking or diverting the exhaust elsewere, it shouldn't matter what you've done as long as the emissions don't change or better yet go down.
-
If you are still looking for an intake air temperature sensor there is a lot of references / cross references for what sensor to use for the TBI 2.5l in the below link.
http://forums.4wdmechanix.com/topic/225-jeep-yj-wrangler-25l-tbi-troubleshooting/
-
i looked at the '95 ohm chart and they are different by quite a bit, but just like the TBI they are the same for the same year (air temp values are the same as the coolant temp values). odd thing is that it looks like all the values are somewhere around 3.5 times higher on the new ones (not that you can really do anything with that info). I think you'll need to find some good ones at the j/y or old stock to make it work as it should unfortunately (or hopefully some store carries them still). I'll make a call tomorrow if i remember to Lordco (in Canada similar to what auto-zone is south of the border, don't think there's Lordco in the US but could be wrong), seems that they sometime have parts i cannot find online so who knows.
-
I found similar info on the sensors. If I use the later model jeep sensors the ecu will think its about 60* cooler for both the air temp and coolant temp so after some more research I found this info on GM sensors on the mega squirt site.
Coolant temperature sensor (CLT)
GM #12146312
(may have been replaced by #15326386)
Standard TX3
GP SORENSEN TSU81
AC DELCO 213-928
NIEHOFF DR134AK
WELLS SU109 MSD 2310 (includes connector)
Air temperature sensor (IAT)
GM #25036751
Standard AX1
GP SORENSEN 779-19001
AC DELCO 213-190
NIEHOFF IGNITION TS83631 was DR-136W
WELLS SU107 MSD 2320 (includes connector)
GM Temperature Sensor Resistance
Degrees F - Degrees C - Ohms
-40º / -40 / 100,700
0º / -18 / 25,000
20º / -7 / 13,500
40º / 4 / 7,500
70º / 21 / 3,400
100º / 38 / 1,800
160º / 71 / 450
210º / 99 / 185
From what I have found these were used several years by Gm so I think I will just go that route.
Al
-
well I called Lordco
they don't have any OEM, but they do have the coolant temp BWD WT5011 that I think chadrc posted, that is $40 (ripoff if you ask me but could not find it on Amazon so i don't have a comparison for it, the alternate GM one AC DELCO 213-928 is $15 at Amazon)
since chad posted the oem part number for the manifold air temp i asked them to look that up and it cross-referenced (according to their system) with Delphi TS10192, they don't have that in stock (and it could be that it is the same item as the OEM and is not available anymore) but the part number might help you out if you can find that one locally somewhere - i searched on amazon and is not available.
as a comparison they do have the GM one AC DELCO 213-190 for the same amount $40 like they have a set price for all sensors (this is the one you listed as a GM alternative for the air temp sensor) - available at Amazon for $20
-
I did some research on the sensors this afternoon and Found that both can be ordered through Autozones website at $15.99 each for the Wells part #'s Su 107 & Su 109. I'm going to try ordering both and see what happens. I'll post the outcome once I get the sensors. I just don't see why something that is used by nearly every vehicle that has fuel injection can be so hard to find.
Al
-
Ok I got the sensors finally. I got the water temp sensor from autozone and air temp sensor from Oriellys. Believe it or not Oriellys had the air temp sensor in stock. It's BWD wt382 a direct cross ref. to the wells 107. Now hopefully I can get this thing running this week end.
Al
-
Sorry it's been so long since I have given an up date, things have been real hectic lately. Ok the engine is in and she runs oh so sweet. She has a lot more power than the old one I have taken her past 4k yet and that was merging on the interstate in third gear but she pulls a lot harder and I did have up to 80 mph up hill where the old one would barely do 70 on flat ground. I did get 5th gear back and it pulls Fairley well. It's no Porsche but I'm happy for now. I did use the tbi spacer that Sharp made and I got from Chardrc but I have had a chance to get the throttle body bore so i didn't use it. I did port match every thing. A few tips though, if you add a spacer on tbi you will have to lose the egr, if you use a Tj engine you will have to change motor mount brackets on the block or at least I did, I opted to run the v belt because I had just put a $140 alternator on it if you do this you will have to change water pumps due to the facts that v belt vs serp they rotate in opposite directions. Also I didn't us the new iat due the fact that I will have to drill and tap the intake to the next size and I was too lazy to take it back off so I put a used stock on in unti I remove the intake again.
Al
-
I was wondering how the egr was going to work with the spacer. I remember I actually had to grind down the TB from sharp to get it to slide down the studs to get around the egr valve. There must be different sized egr valve diaphragms becasue someone made a spacer for tbi on here and was able to keep the egr from what I recall. Glad to hear its back up and running. cant wait to hear what its like with the larger TB.
-
I can't wait til I get time to get the throttle body done as well. I unfortunately for the jeep I'm have to renovate one of my rental property's for my son who is having a spell of hard luck. I'm not sure what the deal is with the fuel milage though, with the old engine it was getting 18 mpg and with the new one it's only getting 15-16. But I guess I can work on that when I do the throttle body.
Al