350 TBI tows 5000/6000lbs

[hpetew]

The stock y-pipe on a tbi pickup is a major restriction, you mentioned changing it and that's a good idea. I know it's a van but I'm sure there made the same way, cut it apart at the merge and you'll see what I mean.

[donforeman]

My project has hit a stop for a week or two. I ordered "made in the USA" vortec heads from Jegs. I wanted to keep the ports small and the EQ heads were rumored to have larger ports in Brezinski's Videos and other posts. The first Jegs head was a little ugly under the valve seats but OK. It looked like it had some type of liner on the valve guides. They were advertised has having bronze guides. I cleaned it up a little and went the the next one. The second head actually looked a little cleaner port wise but had a giant gack on one of the valve stems. Like there was something in the guide and they beat it through anyway. I returned that head and the replacement showed up today with a promaxx number on the box and no "made in the USA" Its the same ugly casting but no liners in the guides and the retainer to seal clearance is only .420" When the other head was .475" clearance. It was a big mistake to order these but live and learn. I think I will call Jegs in the morning and see what can be done.

[Carnut1]

The Eq casting was really nice. I wouldn't worry about the bit larger port. Stock swirl ports are about 183cc. My modded swirl ports are about 200cc. They are a different beast so back to back doesn't work. Thanks, Charlie

[Newold1]

Don't buy or use the Jeg's junk Vortec heads!
It's nice your putting on nicer heads but that is not going to improve your towing with your van.

[rfoll]

When I rebuilt my Vortec engine, I had Oregon Cam grind another 10 degrees on it. I think the cost would be about $75. It might be a good investment while you are working on the engine. http://www.oregoncamshaft.com/

[pdq67]

The Eq casting was really nice. I wouldn't worry about the bit larger port. Stock swirl ports are about 183cc. My modded swirl ports are about 200cc. They are a different beast so back to back doesn't work. Thanks, Charlie

Right Charlie!

My 2.02"/1.60" valve, 200 cc intake port, 50 cc chambered EQ cast-iron heads are dammed near beautiful after looking at my old stock, -461 fuelie big valve heads!

pdq67

[pdq67]

When I rebuilt my Vortec engine, I had Oregon Cam grind another 10 degrees on it. I think the cost would be about $75. It might be a good investment while you are working on the engine. http://www.oregoncamshaft.com/

They any relation to Delta Cams?

pdq67

[pdq67]

Back again! Great thread!

Anyway, years and years ago I played with D2k and ran a series of hy-cams through it for a torque 283 engine.

Spec'ed like.

9.5 to 1 CR;
Flat-top 2 or 4 notch pistons;
Small chambered heads like the old 305HO, -601 heads with 1.84"/1.50" valves and cc them, (53 to 55 cc's here);
.015" shim head gaskets for min. quench;
Small 1.5" dia. 4-tube, long tube headers;
A 2101 Performer and a stock Q-Jet. I know a Q-Jet is listed at 750 cfm, but they only pull what the engine wants at rpm so will be fine, imho.

Nothing fancy.

I found that something like a cam like this had about as flat and as wide a T curve as I have ever seen.

250/210, 104/108, .440" lift. (Now it might have been 250/205, I forget?)...

T was off idle to about 4,000 to maybe 4,500 rpm FLAT before it fell off.

Just food for thought is all............

Please carry-on.

Thanks,

pdq67

[econo racer]

I like the heads style you bought. It think it will work well with a cam maybe 210-218 at 50 degrees

[Newold1]

As I was saying, bigger and better flowing heads will make more power above 4000 rpms over your stocK heads but the small amount of torque they might add over your stock heads between 3500 rpms and 4000rpms won't help your towing because YOU DON'T TOW AT THOSE RPMS!"

Everybody here try to remember, HE IS TOWING WITH A 3/4 TON VAN with a 5000-6000 lb trailer behind it,not performance driving or racing a 3000lb. car! THAT IS A BIG FU**KING DIFFERENCE !!

[levisnteeshirt]

the 1 in open tbi spacer made a nice difference in my truck ,,, I blocked the PVC and put a breather on the PVC valve ,, i put on a 14in open air cleaner and did route the breather hose from the drivers side to under the air cleaner ,, ,, most people don't mention or seem to like blocking the pvc port on the TBI but i do ,, i figure the more vacuum the better and the breather tube going to under the air cleaner from the other side and a breather on the pvc valve itself the engine should clear itself of any combustion gases that get by the rings ,,, its what i do anyway ,, a KN filter or the off brand replica from Advance seems to help too

i dunno ,, you can screw up an engine quicker with a cam thats too big better than anything ,, i would go very very conservitive ,,, i also found one of those marine roller cams but haven't put it in yet ,, the factory cam is tiny ,, without adding any compression from somewhere else ,, its gonna be tough to make any gains with a larger cam for towing , off idle juice ,, with the spacer on my truck pulls down very low staying in upper gears in tight mountain curvy road driving ,, its got to be really low speed before i have to even use 3rd not towing ,,, i would advance the cam very close to the intake valve closing point of the stock cam unless you put in some compression ,, but thats me ,,,, i ran a 3 in single cat with 2 resonators from summit , they look like a glass pack with no packing ,,, no muffler at all ,, 2.5 pipe split after the 3in converter ,, a deep rumble and no drone

[levisnteeshirt]

i wonder if a pontiac type , 30 degree seat would help in a towing SBC

[randy331]

i wonder if a pontiac type , 30 degree seat would help in a towing SBC

Randy

[donforeman]

Thank you for all the advise. I am pretty stuck with these heads. I painted the one, cleaned up the ugliness below the seat and bolted it on never expecting the second one to be such a mess. The second one is going back for the second time. Customer service said they will get me a good one for sure. They are disassembling them to check before shipping. I agree they are junk, no QC. It's taken three to get one so far. I just had not read anything bad about the 555-514080 Jegs Vortec heads online, they hide the manufacturer for good reason and put made in the USA on their ad. I seriously doubt the iron is cast in the USA even. If it's that bad I guess I could toss the one head on craigslist and start over with a different brand, but really for the low rpm I am doing any head will probably be fine if its machined properly.

I don't want to go over the 195 duration for now. The cam is a lot more aggressive than what came out. I do want to try to focus on the 2000 to 4000 range for towing.

[Newold1]

What's the duration and numbers on the new camshaft. What do you think is more aggressive?
Where you install it as slightly advanced will probably help that rpm range a bit.