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Crap. Sorry buddy. Been busy with estimates, my hvac unit died and haven't gotten to garage. I'll be over there tomorrow at around 10 to help a guy move a fridge. I'll try my best to remember.
Haven't spent much time lately on this forum, but this thread is interesting. Guess myself and others waiting to see some dyno results or (other cfm testing) or someone familiar with the aftermarket options for lowers. Any other votes to have one of these sent to Conanski so that he can install and report results compared to his other setups - for testing purposes of course ? I wonder if there might be any issues of actual volume in the lower stock 351 middle section of intake that is also limiting air flow - areas untouched by modifications ? That's what dyno or bench flow cfm reporting would help ....
While there has not been any Dyno testing, there has been flow testing of the 302 truck upper vs gt40 and 351 upper.
There has been flow testing of the 302 truck lower and gt40 and 5liter ho lower, but not that I can remember of the 351 truck lower.
If you have ever looked at these intakes together, you can see that the 302 truck intake is much better. While the 351 truck lower is very much shorter, when you port it to 302 truck size, the short radius isn't an issue, because compared to the other stock intakes it's freakin huge.
My truck is currently stock. I'd love to Dyno it as is and Dyno it after the intake install... But between no money and no time, with it being my daily driver... Makes it tricky.
While there has not been any Dyno testing, there has been flow testing of the 302 truck upper vs gt40 and 351 upper.
There has been flow testing of the 302 truck lower and gt40 and 5liter ho lower, but not that I can remember of the 351 truck lower.
Ok, I am not aware, is there any significant difference between 5.0 and 5.8 stock truck uppers ?
If you have ever looked at these intakes together, you can see that the 302 truck intake is much better. While the 351 truck lower is very much shorter, when you port it to 302 truck size, the short radius isn't an issue, because compared to the other stock intakes it's freakin huge.
Ok, but are ports from that short radius out to the heads - narrower on the 5.8 compared to 5.0 and thus will still flow less ?
My truck is currently stock. I'd love to Dyno it as is and Dyno it after the intake install... But between no money and no time, with it being my daily driver... Makes it tricky.
I agree, and the reason I suggested Conanski seat of the pants as a tester is that he's had different aftermarket products on his trucks ( I believe ) ....
I used the original 5.0/GT40 gasket centered on the 5.8 lower to ink an out line & opened it up left & right with about half of the distance on the top (roof) where the injector protrudes. I barely touched the floor of the port to just clean up the radius where it would transition into the head.
Once I use the burr to rough out the intake what works well to smooth it
Rotary rolls. If you have a harbor freight near you there is approx $ 22 package that has an assortment of 80, 120 at least. I just did a V 6 and had some left over, this probably is about what needed for an 8 cylinder head port job. Aluminum intake should not go thru them quite as fast as cast iron ..... if you look a u tube, you can watch guys in action doing this .....
Smoothing/blending is one thing, polishing is another (I understand we aren't on the topic of polishing, just want to clarify the difference preemptively). Don't polish, and if you have good hands with the correct burr shape, you needn't go any further.
Untamed have you had a chance to measure rocker studs or does anyone else know.
I'm just finally getting to the garage, and only because I had to drop a bunch of stuff off
The stud from seat to tip is 1-15/16 long. So it is probably listed as a 2 inch stud. Mine are 7/16 but you can get 3/8 as well. If you don't want to get guide plates you need to get what's called a rail rocker, that's like the early ones with the guides right on either side of the valve stem. Or if you still have factory style rockers and you can get what's called pedestal mount and they have an alignment standoff that will allow you not to need guide plates.
My studs are also1 15/16. Just did intake broke out on one of centers. Should have or back tomorrow. Not sure how rough to leave surfaces. I know you need some turbulence for air fuel. Tear down and reassembly start this weekend. Does anyone know the color code for wiring on a dodge caravan fan. It was the best match for my radiator I could find.
You're thinking carb application... Ford efi you can polish it all you want. The injectors are right before the valve , and atomization is immediate. There's very little chance of fuel dropping out of suspension in such a short trip. The intake I polish super smooth. The head I use my 120 grit cartridge roll to polish the carbide burr marks smooth, and it gives it a nicely honed texture. Not glass smooth, but very nice.
I've polished many a head... it was until I pulled a set of 210 afr heads to polish the cnc ridges that I gave up polishing intake side altogether. With hopes of picking up some hp, I gained an insignificant amount on the dyno (something like 5 hp) and felt no difference in power. It's not that I was trying to keep the fuel suspended as much as I was trying to smooth flow, I just think it's a total waste of time. There are situations where it is merited (8000 rpm, boost, etc), no doubt, but for most street applications a clean smooth surface is more than adequate.
By all means, if polishing is your policy then go for it...just sharing my experience.
