I have a problem that I think many of us are running into. It is called the '02 Z06. One of my friends has one that is putting out 372 RWHP with just an airbox, bigger injectors and tuning. He is lipping off about how he will walk my ZR1. His car ran 11.83 at 117 on a very cold day. It is usually a low 12 second car.
I have to remove my plenum to put a new vacuum harness on and was wondering if anybody here has ported their plenum and injector housings themselves. I would love to have Mark Haibeck do it, but $2800 is not currently in the budget.
If anyone has attempted this or thought of it, please let me know what you have done. Pictures would be great if they are available. Help me save some dignity and pick up some additional HP before this race. My current mods are in my signature. Thanks for the help.
I did a whole writeup on how to do the housings on the ZR-1 Net. When the net was switched over to the NCM the writeup got lost in the fray. Anyway, I will check at home for the pics I did for it and try and get you a post on the how to tomorrow.
how much is does this run. I am interested in just doing the heads, intake, and inj housing on my 90. I think DRM may have ported the inj housings and intake already, but I'm interested in going to a siamese configuration.
also, I've heard of eliminating the secondary plates and how this isn't a good idea for low end torque. but with the 4.10 gears, I get up to speed quick and wheelspin is a problem. is the chip reprogrammed to just fire both injectors all the time. haven't seen much discussion of getting rid of the secondaries but I think I may want to do that on my car if it would gain some upper end power without sacrificing too much low end. may be a really bad idea, not sure.
I think greg V. is the man I will go to for the porting. anyone better/cheaper??/ greg seems VERY reasonable and nice to deal with.
is pulling the engine the easiest way to get the heads off???
how much is does this run. I am interested in just doing the heads, intake, and inj housing on my 90. I think DRM may have ported the inj housings and intake already, but I'm interested in going to a siamese configuration.
DRM typically does the extrude/hone of the injector housings and plenum. Now don't get me wrong, I am a big fan of extrude/hone, but it doesn't do the same thing as porting does. Basically, it makes what you have more efficient. What it doesn't do is reconfigure, if you will, the intake runner like a port job does.
As far as a "siamese" configuration, it all depends on what you mean by siamese. If all you are intending to do is to remove the bifucation between the runners in the plenum, then that is no big deal. However, if you are taking about removing the metal between the runners and rewelding it, then you are wasting your time and money.
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also, I've heard of eliminating the secondary plates and how this isn't a good idea for low end torque. but with the 4.10 gears, I get up to speed quick and wheelspin is a problem. is the chip reprogrammed to just fire both injectors all the time. haven't seen much discussion of getting rid of the secondaries but I think I may want to do that on my car if it would gain some upper end power without sacrificing too much low end. may be a really bad idea, not sure.
OK, let's just do some reasoning here. A 350 motor can use only X amount of air. If you have the capacity to flow that amount of air, no matter what you do you aren't going to flow any more. There is plenty of breathing ability in the LT5 to flow all the requirements of a 350 with just a bit of porting. Actually, all you have to do is to take the primary runner in the head and enlarge it from 1.26" to 1.33". The secondaries are not touched.
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I think greg V. is the man I will go to for the porting. anyone better/cheaper??/ greg seems VERY reasonable and nice to deal with.
For the 350 motor Greg is about the cheapest there is out there.
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is pulling the engine the easiest way to get the heads off???
You can leave the motor in and do them easily enough. You will have to remove the brake booster on the driver side. On the passenger side, the last two head bolts cannot be taken out fully when removing/replacing. You need someone to hold the bolts out as far as possible and then you can pull the head off. The hardest part of the whole top end job is timing the cams with the motor in the car. You will have to make your own degree wheel that you can tape to the dampener. Also, you will have to grind off some of your socket to fit between the frame rail and dampener so you can turn the motor. Some people will take the whole cooling pack out to get to the bolt in the dampener. If you do that, just remove the whole pack in a limp. You will need to remove the oil lines, cooling lines, and a/c lines before taking the pack out.
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thanks ZR1!!! et all :blueangel:
I am just trying to tell people of screwups before they do them. I have had my share.
Location: Santa Cruz, CA Norcal Vettes Corvette Cowboy
Re: Porting Plenum and Inj. Housings (Quasar Z)
Ron,
I would check with Bill Krishoofer in Mt Washington, KY he is the US rep for Jeal Ind.He was involved with the design of the LT-5. He did my plenium and injector housing after Lingenfelter did a crappy job on them. Don't use Lingenfelter :mad . I don't have his phone number with me but I bet someone here will have it.
Jeffy'
Re: Porting Plenum and Inj. Housings (FrankUrbinati)
ZR1 is also a Jeal rep and his portwork is excellent,too. His prices are very reasonable,also.
DRM was sending their top end parts to ExtrudeHone back in the 1990's but now they are having Greg Van Deventer do the majority of their LT5 portwork.
OK, just ball park (+/- a couple hundred buck), porting the heads, remove some of the divider at the top of the intake, and match port the injector housings, what would the approx cost be??? I would also want to refinish the cam covers and intake too (mine are pretty grungy).
ZR1, I would like a quote from you along with what HP/torque I might get from a stock short block (not ready for a 368 just yet).
Right now I guess I am about the cheapest for plenum and injector housings work. I didn't realize how much cheaper until recently. I gotta cure that. Greg is the cheapest on the head side of things. For a 475 motor he is just rock bottom.
With the top end from me it includes porting polishing of the heads, injector housings, and plenum. If you want the plenum "Siamesed", it is an exra $1600.00. Also included are hardened valve seats, bronze guides, Teflon seals, and locks installed. Competition valve job with radius cuts to all valves and seats as well as pressure testing of the valve springs and replacement (at ccustomer cost) if necessary. Finally, flow bench testing of the heads prior to and after job completion to include a flow comparison sheet. Total cost is $3,500.00.
Not to pick and nits but if you are so unhappy with LPE, why do you have *them* in your sig as modifying your car??? Why don't you have it Billy Kirchoffer(sp) or Jeal modified???:)
Right now I guess I am about the cheapest for plenum and injector housings work. I didn't realize how much cheaper until recently. I gotta cure that. Greg is the cheapest on the head side of things. For a 475 motor he is just rock bottom.
With the top end from me it includes porting polishing of the heads, injector housings, and plenum. If you want the plenum "Siamesed", it is an exra $1600.00. Also included are hardened valve seats, bronze guides, Teflon seals, and locks installed. Competition valve job with radius cuts to all valves and seats as well as pressure testing of the valve springs and replacement (at ccustomer cost) if necessary. Finally, flow bench testing of the heads prior to and after job completion to include a flow comparison sheet. Total cost is $3,500.00.
So how much HP can be realized from a top end job?
Right now I guess I am about the cheapest for plenum and injector housings work. I didn't realize how much cheaper until recently. I gotta cure that. Greg is the cheapest on the head side of things. For a 475 motor he is just rock bottom.
With the top end from me it includes porting polishing of the heads, injector housings, and plenum. If you want the plenum "Siamesed", it is an exra $1600.00. Also included are hardened valve seats, bronze guides, Teflon seals, and locks installed. Competition valve job with radius cuts to all valves and seats as well as pressure testing of the valve springs and replacement (at ccustomer cost) if necessary. Finally, flow bench testing of the heads prior to and after job completion to include a flow comparison sheet. Total cost is $3,500.00.
That would be about 900 6 packs of beer for us MS & AL folk. :cheers:
thanks ZR1!!! that is way cheaper than I thought. Is the siamese intake a good move with only a stock short block??? my inj housing and intake have already been ported by DRM, but I think they just do some pretty minor cleanup for the 450 kit. car just doesn't feel like 450 (108 in the qtr at BG).
I'm looking for a good ZR1 mechanic that can properly retime the cams. I may just go ahead and pull the engine and ship off whatever needs freshening up. I plan to first test the leakdown test, if all is OK, pull the top end off and use the factory short block until it needs a rebuild. every one talks about the high cost of the LT5 but if it lasts as long as I think, it's a bargain!!!
I'm looking to get as close as I can to 500 hp with a factory bottom end and cams (a bit ambitious, I know), and then add another 150 shot of squeeze to get to 650. that is as much as I feel I can hope to hook up on drag radials. anything more than that, I will probably just tear up the tranny and drivetrain.
According to LPE a leakdown test on a LT5 is an iffy thing due to the lifters holding oil and causing false readings. At the time they said they no longer used leakdown tests on LT5 for any diagnosis.
Location: Santa Cruz, CA Norcal Vettes Corvette Cowboy
Re: Porting Plenum and Inj. Housings (Tyler Townsley)
ZR-won,
I reason I have kept the Lingenfelter in the sig is two fold. 1. So people will ask if I like his work and I can let them know. 2. Because if I put pictures of my motor on the web everyone will see the Lingenfelter the Ba%#@ards engraved in the top of my plenum and again ask my thoughts.
Jeffy'
Re: Porting Plenum and Inj. Housings (Tyler Townsley)
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According to LPE a leakdown test on a LT5 is an iffy thing due to the lifters holding oil and causing false readings. At the time they said they no longer used leakdown tests on LT5 for any diagnosis.
Tyler
90ZR1
87 ZR1 EX5014
I've often wondered why the tuners didn't like to do leakdowns on LT5's. You just answered that question,Tyler. The explanation does seem a little strange,though. What's the big difference between LT5 hydraulic lifters and others?
YOu need to remember that BG is a notoriously slow track for mph. When my ZR-1 was stock the best I could do there was 13.07@108. I took the car to IRP in Indy, IN(good track) and ran 12.8s@111.
After I installed the 4.10s, headers and exhaust my best time in BG(I was living there at the time, my 'home' track if you will) was a 12.8@111!!!(you can imagine how happy I was at that point) I took it back to IRP and ran a 12.28@115! After the plenum/injector housings were ported I ran at BG once in May and turned 12.60@113mph. I again trekked to IRP last fall and turned 12.09 at over 118mph! If they hadn't just re-concreted the starting line I could have put it in the 11s(best 60ft time was 2.01) In short, Beech Bend sucks and 108 at BG is probably really 111-113 on a good track; your car probably isn't as down on power as you think.
Corvette Store
Porting Plenum and Inj. Housings
