If I recall, your old 2.8 sounded amazing. I can only imagine how good your setup sounds on your 4.9.


How many dimes did you use to fill the injector holes? /joke

Who all remembers that?

I used some 1" heavy bolts. I can't remember the exact size, but I sized it so the threads made solid contact with the walls of the holes so I had to cut in threads in the aluminum as I turned the bolts home. I used RTV to seal the threads.

Yes, it sounds pretty good. Nice thumpy sound at idle, and as you open it up it gets that raw v8 sound the harder you push.

Arn

I was joking about the dimes.
That was forum drama from YEARS ago.

ohh I remember the Dimes...The good ole "master tuner" or something like that.

Pete

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88 3800 turbo...10 sec Quarter Mile Member.

Good ol MTA Master Tuner Akimoto (sp?)

He could build 4.9s that ran 10's N/A.

I just learned a lesson about used distributors. To do the dizzy conversion I used a 4.5 ci. dizzy and the guts from an Olds dizzy. The Olds gear was not compatible so I transferred the 4.5 gear to the Olds shaft. All worked well, however, what I did not tweak to was that the 4.5 gear was worn.

It was worn so much that it failed with a sudden bang. I wasn't sure what had happened, but, after a tow home and some digging I found the gear on the dizzy had about 1/3 of the teeth stripped down to nubs. It took a special order from the dealer to get a new gear. Once I installed the new gear we were in business again.

I remember Master Tuner's claims and they were a little exaggerated, but, I can say now, that the carbed engine is a far cry from stock. In particular it pulls hard up to 6000 rpm. It seems to be pretty strong.

For anybody doing this conversion, check the dizzy gear for wear. ;-)

Arn

I had the same problem a while back....
in my case the problem turned out to be that I didn't fully seat the distributor gear
... Its a bit tricky getting the gear fully meshed down properly with the cam.

Not in my case. The wear pattern on the old gear was even and centered perfectly. The teeth were just plain worn.

Interesting to note that the old gear was black metal, and the new one is plated.

Arn

I think I figured out the failure.

The gear I put in was definitely worn and a little damaged.



Notice the tops of the lands. They are flattened out. The new one has sharp fins. Also, there was damage you can see that I didn't pay attention to. I guess we mostly learn from experience, so I hope somebody learns from mine.

Arn

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Well, I'm still learning, but I can say this is an impressive ride as it sits. It is getting a 417 ftlb clutch this week because the 290 ftlb clutch lets go under load at 3000 rpm in 4th. It also revs freely and strongly to red line. I still have to get a dyno done.

What I learned today is that the car came with a single core rad. Not much wonder it was struggling with the v8. Being a non-AC car I understand why GM put in a single core, but anyway, now it has a 3 core aluminum.

Getting people asking about it almost every time it is out. It does sound cool and gets admiring looks.

Arn

With the 3 core rad, the temperature situation is now in hand. I had to shackle the front engine mount though because it broke the steel piece holding it to the cradle. (the shackle is a truck spring shackle, ain't no breaking this one)

So I went to the dyno guys. This is a shop that specializes in high end cars like Ferrari's and Porsches, so my Fiero was in good company.

The findings were that the engine was too rich, I had too much advance from 1500 to 3000, (knew that one) The exhaust isn't helping either. I have to yet change it to true duals to help the torque and reduce engine temps.

My torque was suffering below 3000 rpm due to these poor settings on my part.

It was also tested in 4th gear measured at 1:1 ratio so it is measuring a bit low with the actual gear being 0.81:1

This is the test with these flaws built in.

I haven't dyno'd it again with the changes I've since made, but, you can see it as it was tested. I may test it again, depending on the pocket book after I do the exhaust work.

This dyno isn't one of the Mustang variety, as you can see below. It is the full setup for testing all wheel drive cars.



Here is the sheet, max hp at 5300 but not much loss to 6300. and max torque at 3900 with steady loss after that.

You can see my rich condition at over 80% at the bottom.

Can you post a video of how it sounds from a pull away? Maybe a normal and hard on the gas drive away or by.

I can give it a try. Not sure how to post a video but I can do an audio. It does sound totally awesome.

quote Originally posted by Arns85GT: I can give it a try. Not sure how to post a video but I can do an audio. It does sound totally awesome.

I sent you a PM

I was thinking of going for something loud. I just drive it for fun so load is fine with me.

quote Originally posted by Arns85GT: I can give it a try. Not sure how to post a video but I can do an audio. It does sound totally awesome.

Register and get an account on Youtube, then you can upload videos there. That way you can post using the normal way people do on PFF for Youtube videos (just use the edit on someone's thread, if you haven't seen the format before...but I expect you have)

Questions,
How did you hook your tach up?

Did you have cruise control?

I used this thread

I changed the capacitor but I could not find a .064 so I used a .061. It worked. Hope this helps.

Also, I haven't sprung for a new dyno just because I have hesitated to spend the money. (cheap) I also had to beef up the front engine mount.

Arn

I finally put together some cash and went back to the dyno guys at RSP Motorsports Inc.

The settings run this time were platinum plugs, regular 87 gas, and the Moroso heaviest spring for the advance.

This gave, in theory, advance starting at 2500 rpm with 6 degrees on the initial.

As you will see the torque curve smoothed right out maxing at 245 with a nice clean run of 212.2 hp from about 5200 rpm to 5700 rpm.

This is with the stock cam and exhaust logs.

I am pretty pleased with this. It shows that you can put together a pretty solid and dependable system with the 4.9 using HEI for reliability.

The Dyno guys did tell me I could improve the performance with 91 Octane gas and 2 more degrees of initial advance.

But alas, I'm too cheap to buy 91 Octane so it will stay at 212 hp.

[This message has been edited by Arns85GT (edited 10-22-2014).]

Nice! Good to see someone puting a 4.9 on a dyno. I'll be getting mine on one soon as a baseline for tuning.

Stock 4.9's run 10 degrees for 91 octane. FYI. Not sure how your setup will work though.

[This message has been edited by Fieroseverywhere (edited 10-22-2014).]

BTW this is no Mustang Dyno. It is a full 4 wheel drive unit. The installation is worth over a million dollars. They normally test high end cars on it like Lambo's and Ferraris and the like.

I finally made a carb switch. It turns out that the 500 cdm 2 barrel is measured differently for cfm than a 4 barrel

The formula for flow rating 2 barrels goes 3.0 in/hg divided by 1.414 = flow at 1.5 in/hg

The formula for flow rating a 4 barrel is the same but instead of equalling flow at 1.5 in/hg it = 3.0 in/hg.

So a 500 2 barrel flows somewhat less than a 500 4 barrel.

So, I bought a 600 cfm double pumper. WHAT A HUGE DIFFERENCE

Where the 2 barrel made the car quick, the 4 barrel makes it much faster. I'm able to leave solid rubber going into 2nd gear.

I haven't done the dyno, and I don't know if I'll pay the $300 to do it. But I can tell you that the 600 double pump is a significant power adder

The model I bought is the 4776 sa which has mechanical secondaries. The primary jets are 65 and secondary 77. The shooters are #31's
and the cam on the pump is orange #1. The carb came with pink which was too rich.

https://holley.com/products...pumper/parts/0-4776S

I had to delete the egr and build a converter, which is 2 layers of 3/4" birch plywood, lined with JBWeld to make the throat not absorb the gas

Like I mentioned, the engine has become much stronger. In fact, it is impressively fast


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[This message has been edited by Arns85GT (edited 08-15-2015).]