Old boy Tuning?
#17
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Well, the right one has arrived. Did you know i built a 4.7 euro bottom end for scot that was pulled after very limited use. (probably 1-2,000 miles) its basically just broken in, and has completely new components, ready to go.
(ie new seals, all new bearings, cylinderwalls perfect, new rings) It was dynoed at 250rwhp with the euro top end stuff and the US Ljet AFM injection (very restrictive, also spark was retarded at near 20degrees max advance)
so, it is a motor that is perfect for anyone thinking of wanting a new engine at the cost of buying a UNKNOWN used block that could have the results as Dennis has had (7 laps and Kabbom)
Its a 4.7 euro '82 short block. compression rated at 10:1 with euro heads, more like 9.5 with US heads.
Let me know if you or anyone is interested. $1500 and its yours.
Mk
So I second what the others say, a 4,7L S engine is a direct bolt on fit. My best advice is to search for one in Sweden. This week a complete running (but with body damage) early S sold for 10k SEK.
I'm looking for a 4.7 myself, but my current engine is recently rebuilt and as new, so I'm in no hurry. Patiently waiting for the right one to show up.
(ie new seals, all new bearings, cylinderwalls perfect, new rings) It was dynoed at 250rwhp with the euro top end stuff and the US Ljet AFM injection (very restrictive, also spark was retarded at near 20degrees max advance)
so, it is a motor that is perfect for anyone thinking of wanting a new engine at the cost of buying a UNKNOWN used block that could have the results as Dennis has had (7 laps and Kabbom)
Its a 4.7 euro '82 short block. compression rated at 10:1 with euro heads, more like 9.5 with US heads.
Let me know if you or anyone is interested. $1500 and its yours.
Mk
Originally Posted by gruffalo
So I second what the others say, a 4,7L S engine is a direct bolt on fit. My best advice is to search for one in Sweden. This week a complete running (but with body damage) early S sold for 10k SEK.
I'm looking for a 4.7 myself, but my current engine is recently rebuilt and as new, so I'm in no hurry. Patiently waiting for the right one to show up.
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#18
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Best thing you can do for the 4.5 is let it breath. find the euro S intake manifold. also, see if you can find a set of US 85 exhuast manifolds. Out of the US 4.5 we got 220rwhp, but had very retarded timing, but we also had the euro intake and header all running on the very restrictive Ljet US injection. this same set up with a set of euro cams (even with the non euro S heads ) will put down 245rwhp if you have a 4.7 liter bottom end. Just the block change alone with no other mods is near 35rwhp. (ie 4.5 to 4.7.) when we took the 4.7 and went to 5 liter (no other changes) , hp went up another 40hp.
mk
mk
#19
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Originally Posted by mark kibort
also, see if you can find a set of US 85 exhuast manifolds.
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#20
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So really, from what I understand about the 4.5L and 4.7L engines is that the reall horsepower difference is in it's breathing, not just the 200cc capacity. The 4.5L could pick up close to 60hp by using origanal bolt on replacements!
Great I like it.
I did try adjustments on the K Jet system using a 3mm alen key. Very sensitive i found, but was told by the dyno operator that mixture strength was between 15.9:1 and 14.1:1 and thats it (something else wrong?). Is this strange for a K Jet to only give that much fuel?? I think yes??
I have a 1600 mile road trip comming up in a couple of weeks, this should give me time to sort out the mixture/ timing.
I'd like to keep checking this post and maybe hear some feedback from other 4.5L owners on what they have done to get a little more punch from the little big block.
Oh, Mark that short block you have sounds great value, but would probably cost that again to ship it to Australia where I am.
Cheers,
Glenn
'81 9-2-8
Great I like it.
I did try adjustments on the K Jet system using a 3mm alen key. Very sensitive i found, but was told by the dyno operator that mixture strength was between 15.9:1 and 14.1:1 and thats it (something else wrong?). Is this strange for a K Jet to only give that much fuel?? I think yes??
I have a 1600 mile road trip comming up in a couple of weeks, this should give me time to sort out the mixture/ timing.
I'd like to keep checking this post and maybe hear some feedback from other 4.5L owners on what they have done to get a little more punch from the little big block.
Oh, Mark that short block you have sounds great value, but would probably cost that again to ship it to Australia where I am.
Cheers,
Glenn
'81 9-2-8
#21
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I am not anywhere near a dyno to back up my buttmeter, however I just last Friday had a local muffler shop replace my stock '80 Y & cat with a 2" downpipes Y 2-1/2" out(had 2.5" Borla cat-back from PO). Very noticeable increase in low-mid range; my guess would be at least 15 HP from this one change. My understanding is that stock Y & cat are VERY restrictive, and anything you do here is likely to benefit. I am lucky I live in an area without visual inspection; merely have to pass the sniffer.
HTH
Ken
HTH
Ken
#22
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This is my suggestion:
Buy a 78 or 79 with low compression + a kit from Carl. At the same time change you brakes (I believe the old cars can take the S4/GT brakes with a kit?)
An easy setup for supercharger would be 4,5l low compression block mated to S intake, heads and exhaust.
Norwegian government does not ask how you increase power, so a supercharger is OK. You just have to prove that your car don't have more than the brakes was delivered with originally + 15%increase. That means if you use GT brakes, your car can produce 380chp.
If your setup produce to high numbers, you can do stuff like pull back timing or add too much fuel to get below the limit. Or of course change the pulley...
Buy a 78 or 79 with low compression + a kit from Carl. At the same time change you brakes (I believe the old cars can take the S4/GT brakes with a kit?)
An easy setup for supercharger would be 4,5l low compression block mated to S intake, heads and exhaust.
Norwegian government does not ask how you increase power, so a supercharger is OK. You just have to prove that your car don't have more than the brakes was delivered with originally + 15%increase. That means if you use GT brakes, your car can produce 380chp.
If your setup produce to high numbers, you can do stuff like pull back timing or add too much fuel to get below the limit. Or of course change the pulley...
#23
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Hello kjurkic, sounds like the exact same mod I did to my when I first bout it.
Got rid of the exhaust system from the manifolds back to the diff. Replaced with 2 1/4" down pipes into a Y section then 2 1/2" straight to the diif with a 3" 'Hot Dog' style muffler under the floor. That as you said made a noticeable difference down low. The rear muffler is deleted and has a straight through piece with 2 outlets past the rear body. Car has no cat fitted, not required til 1984 in Australia i believe.
Yes Ian928, you are right about the brake upgrade, this would be brilliant with the added safety, and as for the supercharging, I dont see a problem with doing it to the 10:1 engines (M2810), may have to run a little less boost but would have great response and the setup is relatively simple.
Nobody had fuel mixture problems with K Jet systems??
Glenn
'81 9-2-8
Got rid of the exhaust system from the manifolds back to the diff. Replaced with 2 1/4" down pipes into a Y section then 2 1/2" straight to the diif with a 3" 'Hot Dog' style muffler under the floor. That as you said made a noticeable difference down low. The rear muffler is deleted and has a straight through piece with 2 outlets past the rear body. Car has no cat fitted, not required til 1984 in Australia i believe.
Yes Ian928, you are right about the brake upgrade, this would be brilliant with the added safety, and as for the supercharging, I dont see a problem with doing it to the 10:1 engines (M2810), may have to run a little less boost but would have great response and the setup is relatively simple.
Nobody had fuel mixture problems with K Jet systems??
Glenn
'81 9-2-8
#24
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I'm looking into modifying the 85/86 manifold to provide an EGR fitting. This only of concern to 78/79 US owners who live in states with tough smog regs, but if I do make it work and there is enough interest it may become a group buy opportunity.
#25
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Originally Posted by GRTWHT
Nobody had fuel mixture problems with K Jet systems??
#26
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I'm not an expert on K-Jetronic CIS, but I have been working on my CIS issues on a Ferrari for a few months, and I'll share what I've found. It's all about fuel pressure with CIS. The warm up regulator is there as a cold-run enrichment, just like a choke on a carb. When the WUR goes bad, then you can either get too rich or too lean, depending on how the diaphram and spring in the unit has gone bad. I know that's not much help, but it really is unpredictable.
I can tell you that the system is counter-intuitive in regard to pressure. So, a too HIGH pressure on the high or primary side results in too LOW fuel delivery, weird. There is a regulator on the side of the fuel dist that controls primary pressure, in conjunction with the WUR. You can get shims to put under the regulator to make the pressure higher, or remove a shim to make it lower.
Next, there are a bunch of different injectors available for the CIS. They all are pressure activated, but some have different oriface sizes, allowing more fuel in with similar pressure. Kind of like changing the old main jet in a carb.
So, the CIS isn't well suited to making performance increases. there are also restrictions in the throttle plate that can't change unless you are ready to change all 8 injectors and change the settings on the WUR. It is a complex procedure. I looked into it with my Mondial and quickly gave up when I found out what a hassle it was, and how few people understand CIS.
I don't know what your budget is, but I would do as others have advised, and start with a 4.7 if you can find it. Then, you might want to trash the CIS and stock ignition and go to something like the Electromotive TEC3 or similar from Motec. This is better from a track standpoint because you can profile the control unit for the race you're running. Different prefiles can be saved and loaded anytime.
If you stick with CIS, there is a Lambda circuit that can be used to also control the pressure using a feedback loop from a O2 sensor and amp. If that is what they meant by a 'digital' WUR, but I don't know if that's right. they are very costly($6-700), for the parts and your money would probably be better spent elsewhere.
Bottom line, CIS is a pain, and it's getting old, and hard to even maintain stock. Modifying it is a real nightmare.
I can tell you that the system is counter-intuitive in regard to pressure. So, a too HIGH pressure on the high or primary side results in too LOW fuel delivery, weird. There is a regulator on the side of the fuel dist that controls primary pressure, in conjunction with the WUR. You can get shims to put under the regulator to make the pressure higher, or remove a shim to make it lower.
Next, there are a bunch of different injectors available for the CIS. They all are pressure activated, but some have different oriface sizes, allowing more fuel in with similar pressure. Kind of like changing the old main jet in a carb.
So, the CIS isn't well suited to making performance increases. there are also restrictions in the throttle plate that can't change unless you are ready to change all 8 injectors and change the settings on the WUR. It is a complex procedure. I looked into it with my Mondial and quickly gave up when I found out what a hassle it was, and how few people understand CIS.
I don't know what your budget is, but I would do as others have advised, and start with a 4.7 if you can find it. Then, you might want to trash the CIS and stock ignition and go to something like the Electromotive TEC3 or similar from Motec. This is better from a track standpoint because you can profile the control unit for the race you're running. Different prefiles can be saved and loaded anytime.
If you stick with CIS, there is a Lambda circuit that can be used to also control the pressure using a feedback loop from a O2 sensor and amp. If that is what they meant by a 'digital' WUR, but I don't know if that's right. they are very costly($6-700), for the parts and your money would probably be better spent elsewhere.
Bottom line, CIS is a pain, and it's getting old, and hard to even maintain stock. Modifying it is a real nightmare.
#27
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Hey docmirror, I have read some info on the CIS system and gather it's quite simple untill you break down the individual modules to troubleshoot and it becomes really complex.
Think I will replace the filter, (last done in 1999) and see what happens then. It would be nice if the engine was an LH Jet system, then I could put that Autronic SMC system onto it and have progamable fuel and ignition tables, but it's not so easy to do with the old K Jet.
If I could get hold of some fittings to place gauges onto, I could check if the system has all the right pressures, are they hard to come by??
I still think there is 40hp just in the tuning of these engines. (5hp per cylinder) so once I find that then maybe I'll modify things.
Thanks for the tip.
Cheers,
Glenn
'81 9-2-8
Think I will replace the filter, (last done in 1999) and see what happens then. It would be nice if the engine was an LH Jet system, then I could put that Autronic SMC system onto it and have progamable fuel and ignition tables, but it's not so easy to do with the old K Jet.
If I could get hold of some fittings to place gauges onto, I could check if the system has all the right pressures, are they hard to come by??
I still think there is 40hp just in the tuning of these engines. (5hp per cylinder) so once I find that then maybe I'll modify things.
Thanks for the tip.
Cheers,
Glenn
'81 9-2-8
#28
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Glenn, I won't disagree with you if your F/A ratio is off. there may be a few HP avail by tuning. the CIS gauge is avail through JC Whitney
http://www.jcwhitney.com/autoparts/P...fuel+injection
for $60. If you have CIS it should be a part of your tools. I should have one too. I seriously doubt you'll find 40HP by just tuning unless it's really messed up. The only actual tuning that I'm aware of is the CO adjustment as mentioned between the fuel dist head and the air damper, and maybe changing the shims on the regulator spring. anything else is going to be messing with the WUR, the fuel pressures and changing the injector nozzles. Not advisable unless you have the CO meter, variable pressure WUR, etc.
http://www.jcwhitney.com/autoparts/P...fuel+injection
for $60. If you have CIS it should be a part of your tools. I should have one too. I seriously doubt you'll find 40HP by just tuning unless it's really messed up. The only actual tuning that I'm aware of is the CO adjustment as mentioned between the fuel dist head and the air damper, and maybe changing the shims on the regulator spring. anything else is going to be messing with the WUR, the fuel pressures and changing the injector nozzles. Not advisable unless you have the CO meter, variable pressure WUR, etc.
#29
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Thats great, the perfect tool. I'm off to grab this one thanks for the link Doc. I probably was a little ambitious thinking I'll get 40HP out of the little 4.5L just in tuning. 240Hp in stock trim to 280Hp with exhaust opened up and getting rid of that little throttle could do it!
I'll fill you in on my progress once I have the test gauge gear.
Cheers,
Glenn
'81 9-2-8
I'll fill you in on my progress once I have the test gauge gear.
Cheers,
Glenn
'81 9-2-8