HO conversion COMPLETE (tons'a pics pg 7,9)

Topic: HO conversion COMPLETE (tons'a pics pg 7,9) (Read 12069 times) previous topic - next topic

HO conversion COMPLETE (tons'a pics pg 7,9)

February 23, 2007, 02:17:43 PM

Alright, so we finally got my dad's Chevelle running again (the backfiring was caused by faulty points). BUT, on the 2nd run, the oil pump went and dad had to nurse the car home. We had to take the engine back out anyway, so not too bad. Lets just hope no internal damage has resulted.

Back on topic, we'll be taking the Chevelle's engine back out tomorrow. I have all of next weekend off of work, so on Friday when I get home from school, dad and I will get started on the HO conversion. I'm extremely excited, we have almost 3 full days to work with, and I'm just ready to see what my 5.0 was made to do :D . With that said, I will be ordering a gasket set and new timing chain from summit very soon.

Unfortunately, I dont think I'll be able to get the H-pipe ordered for the conversion just yet, so for now I'll be stuck with the crummy Y-pipe (I dont expect it to keep it that way for long though). Also, I've got a set of 3.27 gears to put in the 7.5in rear end.

Installing new rear end gears is probably the only thing my dad isn't 100% sure about doing, and I don't want to spend $165 on getting them installed, so I was wondering if any of you could provide any help.

Any tips/steps/etc about the conversion itself or the gear installation will be greatly appreciated. It's also worthy to note that I have the 5-speed Mustang computer, not the auto (my car is AOD).

I CANT WAIT!!! :D :D

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #1 – February 23, 2007, 03:20:39 PM

Well congratulations on a monumentous achievement.

Can't wait to so how it all turns out.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #2 – February 23, 2007, 03:29:38 PM

Good luck with it! Take your time, have fun and most importantly, don't get frustrated if you end up putting a little more time or money into it for stupid inconveniences.

I'll finally be working on my car next weekend as well (weather permitting)

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #3 – February 23, 2007, 04:00:29 PM

Yeah, thats one reason why I asked dad if we could get started right after I get home from school on Friday; I get home a little after noon, so that leaves us a bunch of time over the weekend. Hopefully we can get it done within that time frame, but if not, I'll have to drive the 85 Trans Am for a week (oh darn!). And also, I have plenty of extra space in my savings account (up until now, I have ONLY used it for gas and kept the left over money as savings). So that should all be ok. Lets just hope everything goes smoothly enough. Especially now that all the ricer guys at school are coming out of the woodwork due to the nice weather, someone has to put them in their place

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #4 – February 23, 2007, 04:15:17 PM

Good luck with the work.3 days should be more than enough time.If you're installing headers,the Y pipe probably won't work right.The 5 speed computer won't work as well as an AOD computer.Find a Mark VII or AOD Stang computer.They're all over E-bay.Keep us posted on everything.Be methodical,and watch what you're doing and all should be well.I would suggest pulling the engine to do all of the mods to it.It really doesn't take that long,and in the long run,it'll probably take less time to do it that way,plus,it'll save you and your Dad's back.just a thought.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #5 – February 23, 2007, 04:20:13 PM

Right on man. Too bad you weren't able to acquire a TC rear end. Be nice to have discs on all 4 corners.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #6 – February 23, 2007, 04:50:12 PM

Come to Ardmore,Ok.There's a TC rear 2 miles from me....still on the car,which there isn't much left of.I know where 3 more TC's are about 50 miles away.I've been picking at them from time to time.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #7 – February 23, 2007, 04:51:26 PM

I heard that the 5-speed Mustang computer will work on AOD cars just fine (and actually have slightly more aggressive shift points too). Would anyone else like to comment on this? I wanted the 5-speed computer because I plan to install a T-5 down the road.

EDIT: From the coolcats site
"By the way, it is acceptable to use a manual transmission computer in an automatic car (but you cannot do the reverse). The timing curve and sensor adjustments are a little more responsive with a manual computer, giving you better throttle response and slightly improved 0-60 times."

Yes, I'll be installing headers and we will have holes drilled in the y pipe to put the O2 sensors in; this is only temporary.

I'm not sure what we'll be doing about pulling the engine out or not. We should have plenty of time to do it, so thats probably what we'll do.

This car will see 4 wheel discs at some point, but not right now. And Ok is a bit too far away :( . A TC rear would be nice though.

Thanks for the tips! Any other comments are welcome.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #8 – February 23, 2007, 05:25:30 PM

be sure all your stupid little electrical connections are alright!

ONE wire, the oxygen sensor harness ground, wasnt grounded, prevented the car from starting!

and ive still gotta sort out this oxygen sensor lean business and actually get that extra 75 hp.

hopefully yours goes better!!! keep us updated and let us know the difference you feel!!!!!!

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #9 – February 23, 2007, 05:33:15 PM

Maybe you should consider holding off on the headers until you can get an h-pipe worked in there. If I'm thinking correctly, headers including factory shortys from a Lincoln/Mustang don't seal or fit quite right on our cars y-pipe. I could be wrong on that though.

You can get away fine with the stock exhaust manifolds for the time being. That's what I did and had no problems. Plus it will save you the extra time/effort of putting in the bungs for the O2s on your y-pipe.

You also double checked to make sure the computer isn't an '89 and up mass air unit right?

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #10 – February 23, 2007, 05:55:15 PM

Yeah, I matched the numbers to those on the coolcats site. I had all these parts bought back last April.

Ok, so about the headers: Would it be a pain to just open the hood and switch out the manifolds for the headers when I do get the H-pipe? Should I go ahead, bite the bullet, and get the $169 H-pipe (which already has holes in it)? Well if I end up having to use the y-pipe for now, I guess I wont even see any benefit from the headers. But, depending on how much I have to spend on the whole thing next weekend, I might be able to order the H-pipe when I get my next pay check.

@Zonda - whats keeping you from getting that hp?

Oh and trust me, once she's up and running, I'll be on here blabbin all around about how she runs. Thanks for all the tips! :D

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #11 – February 23, 2007, 06:06:13 PM

Shouldn't be bad at all. Unbolting the manifolds/headers from the heads isn't a problem. The pain is getting them where they bolt to the exhaust.

In theory, when you get your h-pipe, you should be able to unbolt the manifolds from the heads, cut or unbolt the exhaust before the lers and drop the y-pipe and the factory manifolds as a unit.

Then bolt your new headers to your new h-pipe and put it up into the car as a unit.

I can say that I didn't put my pipe or my headers on my car, a friend who has a shop did it for me. I don't see where there would be a problem but maybe someone else can shed a bit more light on that.

I forgot, are you having cats on the h-pipe?
I bought my catless one with the O2 holes for something like $120.

I think the key is whether it fits your budget. If you feel you can afford it and it won't adversely affect you, then go for it. If you are unsure, the factory manifolds and y-pipe will work just fine for now. I drove with mine for a year after the HO swap and the car still ran great.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #12 – February 23, 2007, 06:15:11 PM

Yes, the H-pipe I'm talking about has cats. I want to steer away from even a slight possibility of getting a fine (we do have emissions here in NC). I'll have to see how much I have saved up before I can make a decision on the H-pipe. Thanks for the installation idea.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #13 – February 23, 2007, 08:22:17 PM

Ok, I just finished calling Summit's tech line because they have 2 different 302 timing chains (on pg160, # SUM-G6514 and G6504) but our cars dont have fuel pumps. The guy told me that the G6504 (with 2 piece eccentric) is the one I should get. My dad is a bit uneasy about it. We also looked through the Jegs catalog and the timing chain listings are confusing (for example, they have one timing chain for 302HO/351W and then a whole different part number just for a 351W). Could anyone shed some light on this? What timing chain works?

EDIT: After a little more searching, it seems that the chain the guy recommended will work, but if anyone has any insight, it is still welcome.

HO conversion COMPLETE (tons'a pics pg 7,9)

Reply #14 – February 23, 2007, 08:37:44 PM

dont get any that say "double roller". the HO engine has a double roller, which is basically two chains right next to each other. the timing gear is essentially two sprockets fused together with a gap in the middle. ours are a "link belt" type. i ran into this trying to get a chain for mine. i just had to get the right part # at advance auto, the first one listed on the site was the roller type.

and about MY hp, i think its running rich. i cant be absolutely sure but if you want the details look for recent threads by me in the Engine Tech section. im getting codes saying the driver side o2 sensor is reporting lean all the time, and the car is actually a little slower than stock, yep no bs, and the gas mileage dropped severely. so i gotta find the bad ground/connection/whatever thats making it dump too much fuel in. i think ill have that nailed down pretty soon though, just process of elimination :hick: