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I got a 1987 Iroc 305TPI a few days ago. It is severely neglected and missing the transmission(was 5spd). Has the G92 3.45 disc posi rear end that the posi seems to be in good shape and functional.
So we moved on to checking the motor. We tried to crank it by hand. Removed all the spark plugs and tried after that and it still won't move. So it appears it is locked up. It's been sitting for years. The oil coming out didn't look bad at all and we flushed 6 quarts through it before we attempted this. The last spark plug we pulled (very back of motor on driver side) made a hissing noise when the plug came out and the tip of the plug smelt like coolant.
One of the plugs had a decent amount of corrosion on the ring of it the rest just had a little bit of carbon build up. At this point, I'm expecting the worst, and thinking I need to replace the motor. I think the tpi stuff is all good but the bottom end might not be.
What I am wanting to know is if I can use any 305 bottom end and replace it with this one, as long as it's an 87 or newer so that it's a roller. I would assume that the TBI and TPI 305 bottom ends were identical, but just wanted to make sure. I know of a few places to pick some up for cheap. I wouldn't be opposed to having it rebuilt but it would probably cost a lot more to have that done then replace the block.
I'm going snooping at a junkyard tomorrow to try and scope one out.
I wouldn't be opposed to pulling a lower 350 block but I don't want to do much modification quite yet.
Any advice as usual would be greatly appreciated.
Last edited by AmpleUnicorn88; 01-02-2016 at 11:36 PM.
Any 305, 87-96, will bolt in the same place using the same bolts as the original. Truck 305's won't even have a roller cam but it will bolt in the same. Heads and cam will be different on anything that isn't a TPI 305. Even earlier tpi/automatic equipped cars will have a different cam.
Any 305, 87-96, will bolt in the same place using the same bolts as the original. Truck 305's won't even have a roller cam but it will bolt in the same. Heads and cam will be different on anything that isn't a TPI 305. Even earlier tpi/automatic equipped cars will have a different cam.
That was essentially what I was thinking. The plan was just to try and crank this motor to see if it was locked before pulling it. It was getting pulled regardless. The plans are also to get a different cam and I was going to have the heads checked out. But with the potentially head gasket issue, I may need new heads unfortunately. I did read the trucks didn't switch to rollers until the vortec came out in 96.
I'm contemplating going with a 350 lower right now too, and just reusing all the tpi stuff. The fuel pump is also going to be changed so could upgrade as well at that time. Which really sucks because a few months back a junkyard had a 91 firebird they got in with a rebuilt 350 TPI and they sold it finally to some guy for $100.
Pour some Marvel's Mystery oil into each of the plug holes and try to crank it over each day - with some luck it should free up.
I have read a lot of things online to try stuff but I feel that won't solve the real issue of why it locked up to begin with. It might free it up but when I open it up it might be pretty corroded and damaged beyond fixing or cost too much to repair. Picked up a lower end 305 out of an 89 Firebird TBI. So I'm probably gonna end up using that.
This is the 305 lower end I picked up today. Came out of an 89 Firebird 305 TBI. The cylinder walls look really clean and the heads were pulled somewhat recently and had the gaskets replaced. Can't tell of any further work so not sure if it had any work other than gaskets done or what but the lower end of this motor is in really good condition. Way better than my 88 TBI looked like when I got it and it runs pretty good right now.
Any who, anybody know what the deal is with this block? I haven't opened my 88 TBI up to see but I swore I read on here that all the motors were roller blocks starting in 87. My buddies 91 305 TBI has that plate for the lifters in it but this motor does not. So did they not make all of these motors hydraulic rollers and is this one a different kind? I don't know what's in the 87 iroc or if they are still good. I didn't take any of the rockers or the heads when I pulled this. Anybody shed some light on this? I believe this is at least set up for hydraulic lifters so I could buy them but was this supposed to come with that spider or whatever that plate is refered to? Again, it came out of an 89 Firebird TBI. Don't know what the iroc looks like yet either. That will probably get pulled next weekend.
Last edited by AmpleUnicorn88; 01-03-2016 at 11:04 PM.
So I answered my own question but sprung some more up.
According to what I believe to be the casting number on this block, it is a vortec 305. Casting #10243878 which shows up as a 96-97 vortec 305 on the searches I did. I can't remember the casting numbers on the heads but the last 3 # were 181 or 183. That 3 maybe was an 8 but not positive.
Any who, I pulled a lifter out to check because it didn't have the spider installed, and it has flat tapet lifters installed. Here are some more pictures of the block I took. It's in super good shape which makes sense now that it does considering the firebird I pulled this from was an 89 and it has 173k miles on the odometer.
So now my new question is will there be any issue with this motor working with my TPI stuff from my 87 iroc? This motor had the TBI intake manifold and I believe TBI heads bolted to it and it ran at some point like this. I sort of feel like this is a dumb question since it appears pretty identical to my 305 TBI block, but just checking to see if there are any differences big enough to prevent the TPI stuff from being a straight swap. If I can reuse the lifters from the iroc I will otherwise I will have to buy hydraulic roller lifters, but I'm swapping the cam to a roller aftermarket one. Just wondering if there is any reason this can't happen.
Last edited by AmpleUnicorn88; 01-03-2016 at 11:10 PM.
I'm hoping to do as little tuning as possible because I am unfamiliar with it. My buddy has the tuning software for his 91 TBI and I sort of understand the very basic principles of it, but I was thinking tpi needed less tuning because of the maf system at least on this 87 iroc. I do intend on putting in an aftermarket camshaft however I don't know which one yet. I want a better than stock one but I don't want to tune it. Or minimal tuning if I have to take it to a shop.
I am pretty sure the vortec 305 is essentially the same block, just newer. It came with better heads and cam I believe but not sure on the cam. The one I pulled looks newish still but has flat tappet cam and lifters despite it being a roller block.
I'm hoping to do as little tuning as possible because I am unfamiliar with it. My buddy has the tuning software for his 91 TBI and I sort of understand the very basic principles of it, but I was thinking tpi needed less tuning because of the maf system at least on this 87 iroc. I do intend on putting in an aftermarket camshaft however I don't know which one yet. I want a better than stock one but I don't want to tune it. Or minimal tuning if I have to take it to a shop.
I am pretty sure the vortec 305 is essentially the same block, just newer. It came with better heads and cam I believe but not sure on the cam. The one I pulled looks newish still but has flat tappet cam and lifters despite it being a roller block.
I'd use the original TPI 5 speed cam if it's still in good condition. It is a fairly good cam despite being factory. The specs were #14093643 202/207 .431/.443 114.5. I think that's the correct one for 87 manuals. Otherwise if you go aftermarket you can go to a slightly hotter cam and the ECM SHOULD compensate to a certain extent. Exhaust on this is more substantial of a bottle neck over the cam.
I'd use the original TPI 5 speed cam if it's still in good condition. It is a fairly good cam despite being factory. The specs were #14093643 202/207 .431/.443 114.5. I think that's the correct one for 87 manuals. Otherwise if you go aftermarket you can go to a slightly hotter cam and the ECM SHOULD compensate to a certain extent. Exhaust on this is more substantial of a bottle neck over the cam.
Well if it's still good and I don't stick with it I'm sure somebody would buy it off of me. The motor for this iroc is low mileage I believe. It's just sat for so many years. Not sure how well a camshaft holds up over time of not being used. I know that pitting can occur though.
I hope the lifters and rods are still good though. I wasn't really planning on buying new ones.
Exhaust will be changed. I'm thinking the hooker 2055's. Not sure on muffler and cat yet though.
My next question is what heads fit on the vortec 305 block I picked up and still allow the TPI manifolds to mount? There are a few good deals on craigslist locally for some heads that have been machined already, and I'm not sure what the differences were throughout the years as far as what can and can't bolt up to them. I don't know what valves were in the tpi heads but I'm assuming they were a little bigger than the TBI heads. I have been looking through so many casting numbers tonight and I haven't found anything anywhere that says what heads will work with a TPI setup without modification. I don't want to downgrade either so I either want TPI heads, or equivalent or better. I am hoping to get the motor out of the Iroc this weekend to take a closer look but since the lower end is locked, I'm guessing there is going to be quite a bit of rust and I'm assuming at this point nothing is salvageable. Which sucks because this iroc definitely has low (well low to me) miles on it it seems.
Most 305 heads (if not all) you find will have 1.84 int 1.5 exh valves. TBI heads will bolt the same but the ports will be different, as in not as performance orientated. 87-95 heads will bolt the same. 96 and later need a vortec TPI base to work (I wouldn't suggest spending the money on it for a 305). 86 and earlier heads will have the center bolts at a different angle. The holes on the intake can be elongated out to work for those four center bolts.
I'd look at the heads you have before you go to far. The tpi heads may be retainable with little effort or the heads off this new motor may be ok heads.
Most 305 heads (if not all) you find will have 1.84 int 1.5 exh valves. TBI heads will bolt the same but the ports will be different, as in not as performance orientated. 87-95 heads will bolt the same. 96 and later need a vortec TPI base to work (I wouldn't suggest spending the money on it for a 305). 86 and earlier heads will have the center bolts at a different angle. The holes on the intake can be elongated out to work for those four center bolts.
I'd look at the heads you have before you go to far. The tpi heads may be retainable with little effort or the heads off this new motor may be ok heads.
That's essentially what I have found. I am just curious as to what my options are if the heads on this TPI motor are no good. I thought I read the TPI heads had 1.94 valves though. I just want to have as much information as possible so that I know when the time comes if the heads on the iroc now are bad. I'm expecting rust everywhere when I pull it since the crank is seized up. It would be nice if the heads are in good shape and the lifters and rockers etc because that would save me quite a bit of money and I can put that toward the exhaust which is the most crucial thing. If the heads look ok I'm gonna have them cleaned and checked, maybe even some slight porting but that will depend on how much money I have to put into it.
The tpi 305 valves were still 1.84. I would expect those heads to be useable, but I'd put as little money as possible into a 305. If those heads need guides, valve jobs or valve seats, the price tag goes up quick. I wouldn't have a shop port them, not really worth the cost. Especially on a 305. I'd probably stop at a cleaning, seals and springs on those heads. There are too many dirt cheap 305 heads out there to waste money on a set that need a lot of help.
Go with a T56 6 speed tranny. Thats what I got. Omg so much fun �� If your shifters there already oh well I know you got alot going on your plate right now stick with your T5
The tpi 305 valves were still 1.84. I would expect those heads to be useable, but I'd put as little money as possible into a 305. If those heads need guides, valve jobs or valve seats, the price tag goes up quick. I wouldn't have a shop port them, not really worth the cost. Especially on a 305. I'd probably stop at a cleaning, seals and springs on those heads. There are too many dirt cheap 305 heads out there to waste money on a set that need a lot of help.
I guess the only difference between the tbi and tpi heads was the porting then? Because I know a lot of people seem to prefer the tpi heads over the tbi heads, which seems odd if that's the only difference in the heads.
Go with a T56 6 speed tranny. Thats what I got. Omg so much fun �� If your shifters there already oh well I know you got alot going on your plate right now stick with your T5
Yeah, I would love to do that. T56's around here go for close to 2k used and in ok shape and 100-200k miles on them. It's cheaper to buy the entire car and then Rob the transmission from it then sell the motor, unless you want to swap that as well. I may one day swap to a 350 TPI as well.
Well its all about research, your budget and your grease monkey mechanics to come through for you. Ask yourself first before you do all this work??? Do I Love my shell ? I mean it is an 87 which is kool already (plus mine is to hehe). Second ask yourself? Whats reality and whats going to make me happy? Im 37 and talked to all kind of 3rd gen owners and it seems like ita a neverending story. Its like finding the perfect wife, big ***** big butt nice hair feet and hands. Is her motor good. Does she have a good heart?Will she cheat on me in the long run? Thats how I feel about it. Im in Love with my IroCZ but like everybody there's always room for improvement. Just do your reasearch and see what benefits you and makes you happy. After so many years I finally found her in Az and Im happy. Just cosmetics for now. Still anybody knows a electrical camaro guru tech in California plz let me know !!!
What were the casting numbers on the heads that came with the 305 you just got?
I didn't take the heads. I have the lower block with the crank, cam, lifters, and timing chain/cover as well as Harmonic balancer. It was $150 for all of that.It would have been about $120 more with the heads.
I don't quite remember what the casting number was but I do remember it was either 181,193,187 or 197. One of the heads had what looked like a 9 where it looked like an 8 on the other side. I believe the stock tbi heads were taken off the older motor when it was swapped for this vortec 305 and put on the vortec.
Well its all about research, your budget and your grease monkey mechanics to come through for you. Ask yourself first before you do all this work??? Do I Love my shell ? I mean it is an 87 which is kool already (plus mine is to hehe). Second ask yourself? Whats reality and whats going to make me happy? Im 37 and talked to all kind of 3rd gen owners and it seems like ita a neverending story. Its like finding the perfect wife, big ***** big butt nice hair feet and hands. Is her motor good. Does she have a good heart?Will she cheat on me in the long run? Thats how I feel about it. Im in Love with my IroCZ but like everybody there's always room for improvement. Just do your reasearch and see what benefits you and makes you happy. After so many years I finally found her in Az and Im happy. Just cosmetics for now. Still anybody knows a electrical camaro guru tech in California plz let me know !!!
I feel like I have a ton of research into these third gens from when I bought my base 88 almost a year ago. I was planning on a full restoration on it and I was actually looking for a new dash shell when I found this iroc and changed gears because the body was mostly straight and has no rust. It has all the options I was going to convert my 88 over to since my 88 came with nothing, not even AC which me and a buddy already converted. So now I don't have to do any of that, plus I have a working posi 3.45 G92 rear end and some working (hopefully) TPI stuff so if I want to switch to a 350 it would be easy.
Time will tell if this was a mistake or a good idea.haha.
I have no experience switching around tpi to tbi heads in a 305 (I do on a 350 tho) so I have no first hand knowledge on this but a knowledgeable moderator posted this years ago. Just food for thought.
Originally Posted by ShiftyCapone
Although it may appear dim, new light has been shed on siwrl port heads. When ported they can produce decent flow numbers for low RPM motors. In stock from the 187's outflow the 416/081's on the exhaust side but do not on the intake side. The jury is still out on which side is better to err on. A few people have flowbenched these heads in ported and non ported stages and disscussions of each are covered in some of these following threads. The decision is up to you weather or not you want to use them. You will never get the same performance out of a a swirl port head as compaired to a properly ported set of 416 or 081 heads. However, when untouched those heads (416's and 081's) are only margonaly better. Tuning and cam selection are keys to making power with these heads. Dewey is running 14.5's with his untouched stock 187 heads. You need to choose a cam that works well with the low RPM flow advantages of these heads. Read the following and judge for your self. More and more track data is starting to come up which is changing all previous attitudes on swirl port heads. I was a huge skeptic until I started seeing this data and looking at peoples track times with proper chip tuning. I have not made a formal decision on which heads I would choose for a TBI application. I honestly have been shocked by the results some people are seeing and it is hard to ingnore their recorded flow/track time results. If you have no money at all and cannot fully take advantage of a 416/081 head, then the swirl ports can be used. You limit the future potential with swirl port heads when compaired to other GM castings. However, if you have a low RPM motor it may be a viable consideration.
I have no experience switching around tpi to tbi heads in a 305 (I do on a 350 tho) so I have no first hand knowledge on this but a knowledgeable moderator posted this years ago. Just food for thought.
I think I remember reading this a few months back bucks couldn't find it again. The search box on this site is hit or miss and usually I Google what I want and then find the third gen link.
But I have basically read that the TPI heads are slightly better due to the TBI being swirl port heads I believe. I don't know if I will get anything done to the heads I will be using, unless I can find a good deal on heads that have been pressure checked, cleaned, and maybe a valve job and some porting. My buddy spent I believe $400 ish on his TBI heads getting them cleaned, checked for cracks, bigger valves and slight porting. I'm not looking to spend that much but I want to do the bigger valves it that will help much. I plan on doing an upgraded cam too. The vortec I picked up is a roller block set up, but came with a flat tappet cam and lifters. It has the ability to have roller cam and lifters installed as well as the 3 holes threaded for the spider plate. Which I'm sure will still be good from the iroc so I will probably reuse those so I will be going roller. Depending on funds I might have head work done or buy nicer heads so that I can always swap them onto a 350 later. I know people say just to do a 350 but I want to stick with the 305 for now.
My main concerns are with the newer vortec motor working with the older stuff.
My main concerns are with the newer vortec motor working with the older stuff.
The vortec short block should all be direct replacement. If in doubt, check 350 vortec swaps. As I recall, if you use older style heads then everything transfers over.
The vortec short block should all be direct replacement. If in doubt, check 350 vortec swaps. As I recall, if you use older style heads then everything transfers over.
That's kind of what I was thinking. This motor had the tbi intake on it when we pulled it. I am just not quite as knowledgeable here so I am just wanting to make absolute sure.
The block is the same. As you can see the truck motors did not get the roller cam treatment but the block is provisioned for it. You can use all the hardware and cam from he original motor and have no issues at all. You can also bolt the original 1987 heads on and have no issues. Have fun!
The block is the same. As you can see the truck motors did not get the roller cam treatment but the block is provisioned for it. You can use all the hardware and cam from he original motor and have no issues at all. You can also bolt the original 1987 heads on and have no issues. Have fun!
Yeah it had the flat tappet stuff. I'm glad they at least made it a roller block set up.
I got the heads off the iroc motor this weekend and the lifters and spider look good. Some wear marks on the sides but the rollers have no pitting or corrosion and not really that scratched up. I cleaned them really well and then dipped then all in fresh oil and then put then in a Ziploc bag and poured some more fresh oil over them.
Not sure how to tell if the rods are still good or not.they are covered in carbon buildup but none of them look bent. Rockers arms seem fine.
Not sure if I'm keeping these heads or getting different ones.
Hopefully this is the right place to ask, but I am having trouble finding somebody on here that burns chips. I don't know anything about tuning myself however I have read stuff on here that some member (can't remember the name) has posted on several posts explaining what is needed to DIY which I will probably pursue. But for now, I am just looking for a reputable person that has burned chips for people on here that can burn a chip for my iroc. Not sure how much more info I will need to give but here is what I know now:
It's going to be a 305 TPI. The block is a vortec 305 96 and newer. Stock crank and unmolested. It's going to have an aftermarket roller cam but not sure which one yet. Already have the entire intake system- Edelbrock lower intake manifold that's ported, edelbrock high-flo runners, corvette plenum, TPIS(not 100% sure but was told it was ported by them) Throttle Body, injectors are bigger (was told 27lbs but need to double check, I might scale down). I'm planning on going with the Hooker 2055 headers and y-pipe setup as well. I'm going to be deleting the smog pump and everything related to it, and I might bypass the EGR as well. Keeping AC.
I'm sure I will have to go more into detail but figured I would give a background now in case it helps with a recommendation for a burner.
Thanks in advance. I apologize if this is the wrong place to ask.
The man to talk to around here was 'Tuned Performance' but he has had some health issues preventing him from providing PROMs for tgo. I haven't seen him on since November. You may want to start a seperate thread in hopes someone else is out there. My suggestion though is to check locally/regionally. Dyno tunes are much more effective and accurate. Otherwise, if you think you can handle it, start tuning yourself. It's not as hard as it seems but there is a lot to pick up on. If you switched to EBL flash then it's a bit easier as tuning it doesn't need chips and burning equip. Plus EBL is filled with support on tgo. I'm partly biased since that's what I use on my 92.
And those 27lbers are huge for that 305. 22's (factory 350) may be a little big and the original size 19's are probably still enough.
The man to talk to around here was 'Tuned Performance' but he has had some health issues preventing him from providing PROMs for tgo. I haven't seen him on since November. You may want to start a seperate thread in hopes someone else is out there. My suggestion though is to check locally/regionally. Dyno tunes are much more effective and accurate. Otherwise, if you think you can handle it, start tuning yourself. It's not as hard as it seems but there is a lot to pick up on. If you switched to EBL flash then it's a bit easier as tuning it doesn't need chips and burning equip. Plus EBL is filled with support on tgo. I'm partly biased since that's what I use on my 92.
And those 27lbers are huge for that 305. 22's (factory 350) may be a little big and the original size 19's are probably still enough.
I just checked and the injectors in the fuel rail are Ford F5DE-B5A which comes up as 24lb injectors. I have read on here that some people have had some fitment issues with them so they had to modify the port where the injector sits or add another gasket. They are currently sitting in the housing so I'm guessing one or the other has already been done. Either way, I'm thinking these are super big for a 305. I am planning on getting it tuned but I'm torn on keeping them or getting different ones because if I swap to a 350 or do a 383 these should still be ok to use. Not sure if I will ever do that but I will have to buy other injectors and I am not really looking forward to having to spend more money on this intake setup.
Being a MAF system you can change cam to a certain degree and the computer will compensate without a retune. If you're keeping the 305 (which I would suggest by now since you already spent money on it) then just get a set of 19lbers and sell the fords. They're not that expensive. People spend a lot of money trying to keep parts they already have. Retune if you have to after you have it together.
If you change to a 350 or 383, save up money and science out a build, don't waste time or effort worrying about having parts for it now. By the time you get that far you'll change your mind or something else will come up and change things. Take it from experience.
I took my heads to a shop today and they said they are saveable, assuming they aren't cracked. They won't charge me anything to have them cleaned and magnafluxed either. They quoted me $1100 for the head work and comp cam.
What I am wondering now is what cam to go with. I want to have a nice sound and performance. It doesn't necessarily need to lope hard but that wouldn't be too bad. If anybody has any recommendations on a camshaft I am all ears. Looking to do a roller cam.
absolute biggest I'd recommend is a 8-501-8. Its what I have in my 350. Personally if I spent the time on a 305 I would use a 8-500-8. The intake limits you even if the ecm tuning didn't. Not that there aren't lots of cams to choose from, someone else might select something different.
The one that the guy at the shop recommended was 8-502-8. I took a picture of what he wrote out.
I told him I wanted bigger valves. He also pointed out that one or 2 of the exhaust seats were messed up and that they were sitting lower than they were supposed to, so those need to be replaced. Both heads have quite a bit of corrosion but the guy said it's no problem as long as the heads aren't cracked. Which he isn't going to charge to clean and magnaflux the heads.
He also said if I paid cash they might take some money off and if I say that I don't want to pay that much they can take some money off. I put a call in to the place my buddy had his heads done and they are supposed to call back tomorrow to give me a quote over the phone. There's a few more places I'm going to call in the area as well. I don't really know much about head work or camshafts so I don't know if this is a really good deal or not. I know people say that comp cams are the bees knees, but I am not set on a particular brand. This will be my daily for a little while after I finish assembling the car.
A stock 5 speed MAF tune will run an aftermarket cam. We used a Comp 08-302-8 in an 88 TPI and it runs great on the stock tune with stock 19lb injectors. Only issue is that it's a bit rich at idle, but other than that, it's awesome.
Yeah I immediately found the same cam on summit for the price you just stated. So if I wanted to go with that cam, I would talk to them about that and see what their response is. They aren't opposed to me getting my own cam and using it at all, this was just a recommendation to use but they said any of the other comp cams they have listed would be good. They were basing the pricing off that for the springs.
I don't know much about cams, so things like the specs I don't fully understand yet. I just don't want to go with too big of a cam. Don't suppose you or somebody else knows the maximum cam that can be used in a 305 block tpi setup using the stock heads (which will have some work done and rebuilt, assuming they are good)? I think I remember reading that once you get to the 500's for lift is when there could be issues, so if I stick with one below that, will I run into any clearance issues or performance problems?
I know Elgin seems to be pretty cheap and a buddy of mine is running one of their cams in his tbi and it sounds great and seems to be good performance wise. I am unsure as of yet if I'm going to get new lifters or reuse the ones I pulled from the motor that was in the iroc. They aren't pitted or damaged and the oil in them was still somewhat clean and a medium yellow color.
I'm not set on any brand and the cheaper the better, but that doesn't mean I want the cheapest cam. Also, I have bigger injectors, and I am either going to use them (Ford 24lb) or buy some 350 injectors (can't remember if it was 21 or 22lb). Somebody recommended a guy on eBay and I checked him out and he has nothing but good reviews so I sent him a message. I talked to him for awhile and I think I'm gonna have him burn me a chip, so regardless of what work I have done, I'm going to have a chip burned.
Your "maximum cam" is limited more by the intake than the heads. You set the heads up for the cam with proper springs etc. At some point the cam can have too much lift to where the heads aren't flowing well at that lift even if you don't have clearance issues. The long runner, small tube intake limits the duration and where you want your timing events to happen. The INTAKE is your current bottle neck and what you have to work around. All three cams, the 500, the 501 and the 302 fit that bill.
Take the roller lifters apart and clean them, then reuse them. More often than not they are fine.
Again, use 19 lbers. They'll be way easier on the tuner and yourself.
The intake I am using I believe was set up to be used on a 350, which is why the bigger injectors were put on. The plenum is from a corvette and has been ported, the runners are edelbrock High-Flo runners, which might be siamesed, but I haven't taken it apart yet to look at them, but there are 2 runners combined for each 4 pieces. and the lower intake manifold is an edelbrock ported manifold as well. guy gave me the gaskets he matched to it. Not sure if that is going to matter in terms of recommending a cam, but I think the stock specs on the tpi cams are pretty good. Many people recommend staying with the stock profile, but I want a combination of the sound and performance to be had from upgrading it. I am already planning on getting a new one since the camshaft that is in the iroc motor right now has been sitting for years and years and I figured I would just replace it anyways, so might as well upgrade.
If those runners are siamesed then maybe something like the 501 or 502 depending on how far siamesed they are. The long runners are still a big factor when picking a cam. Still wouldn't go much bigger on a street 305, but maybe that's just me. And personally I'd still use the 500.
What is your opinion on the LT4 hotcam? I have read on here a few people have ran those and are pleased. It's less than .500 lift which is what I'm trying to do. Summit says it's duration at .5 218/228 and .492/.492 lift. Still might be a tad too high though.
Yeah I'm strongly considering going with the Elgin cam my buddy got. I believe it's 1136 part number. 210/215 .462/470 lift and 100° LSA. From everything I have read that's probably a good all around cam for these engine and won't have vacuum issues.
So I came up with another question. The iroc was missing the negative battery cable. So, how the heck does that thing get routed? Obviously it connects to the negative terminal, but I am unsure of how it routes afterwards, to wherever it is bolted to. I can probably do it however I want as long as it is grounded correctly, but I am wondering what factory was.
01-02-2016, 07:28 PM
