Intake swap thought

[L31MaxExpress]

I think this air hat alone is the reason the vans are rated 245 hp rather than 255. I even looked at trying to use a stud width 4" dryer duct elbow and it would not fit either even cut down. I was going to slide a piece of 3.5 ID silicone hose in it that is 4" od, epoxy it in place, weld a lip in the throttle body and press it on. But even the stud width elbow hits the firewall. The 4" dryer elbow has 3x the internal cross section area of the stock inlet hat.

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[Supercharged111]

Would it be cheaper and easier to mod the dog house vs swapping the intake?

 

[L31MaxExpress]

I will know more of the port alignment, port size and overall quality of the manifold when I have it in my hands. That being said I have had my hands on the Edelbrock LS version of this manifold. It is a course sand cast manifold. The runners are absolutely rough as can be and lots of casting flash. The china knock off looks like it is foam cast. Externally atleast it looks much less granular and smoother. Edelbrock wants over $800 for the manifold and fuel rail. For $368 shipped it was impossible not to order one to atleast check it out.

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This is a picture I found of the Edelbrocks internal casting.

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[L31MaxExpress]

Would it be cheaper and easier to mod the dog house vs swapping the intake?

Its not the dog house thats in the way. Its the metal body structure under the wiper cowl. Posted this picture earlier. That bonnet is really sandwiched in there. Dumb on GMs part not to have just put a LT1 in these vans. Could have used a B-car engine, low mounted compressor and all. Then again I do not know why all these trucks did not get a TPI or a LT1 except that GM likes to cheap out and fall behind. The spider was trouble when they first came out with it in the 92 4.3L CPI and GM was well aware by 94 much less 95 they had problems with them. My uncle lemon lawed his 92 S10 Blazer because of the spider when it was new.

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[tayto]

i thought TPI lacked too much low end for heavy truck use? I assume GM dropped the LT1 (and reverse cooling) because of the stolen property lawsuits. interested to see the intake& results....

 

[L31MaxExpress]

i thought TPI lacked too much low end for heavy truck use? I assume GM dropped the LT1 (and reverse cooling) because of the stolen property lawsuits. interested to see the intake& results....

GM could have easily changed the rear-end gearing to get the TPI to where it needed to be to pull the truck down the road. Like I said it was a cost thing. GM kept the Q-Jet after other manufacturers had gone to EFI. Then they kept the TBI well after other manufacturers had port fuel injection. Then the spiders. Took until 1999 to get a proper EFI system on a GM truck with the new GMT800s and until 2003 for them to put a decent fuel system on the V8 vans (except for the 01-02 8.1Ls). GM had sequential port fuel injection and distributorless ignition in about 1985 on some of the V6 cars.

I think the LT1 got abandoned because of the GenIII myself. With the B/D cars getting phased out in 1996 and the Corvette going to the LS1 in 1997 that only left the F-cars with the LT1 for the 97 model year.

 

[b454rat]

Isn’t that intake the same as the ramjet? Curious to see how it works. I have the ramjet intake, tried to sell it with no luck. Once get the Yukon running right might swap it on.

 

[L31MaxExpress]

Isn’t that intake the same as the ramjet? Curious to see how it works. I have the ramjet intake, tried to sell it with no luck. Once get the Yukon running right might swap it on.

Similar but different. This is a clone of the Pro Flo 7137 manifold. It has 6" long runners opposed to the 4" long runners of a Ramjet intake. The longer runners should drop the torque curve a few hundred rpm lower than a Ramjet intake.

 

[Pinger]

Shouldn't MAF fall off after peak HP too?

No, not necessarily. The MAF could still be increasing but not enough for the rising rpm which results in less full cylinders and lower torque. Maximum power is when the torque reduction is greater than the rising (with rpm) mechanical friction. It is the intersection of falling torque and deteriorating mechanical efficiency that determines the rpm of maximum power.

 

[0xDEADBEEF]

When I look at that picture, I wouldn't want anything to do with an intake R&R.